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Duke University

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Evaluations

Publications of Daniel O. Schmitt    :chronological  alphabetical  combined listing:

%% Book Sections/Chapters   
@misc{fds201331,
   Author = {D. Schmitt},
   Title = {Primate Locomotor Evolution: Biomechanical Studies of
             Primate Locomotion and Their Implications for Understanding
             Primate Neuroethology},
   Pages = {31-61},
   Booktitle = {Primate Neuroethology},
   Publisher = {Oxford},
   Address = {London},
   Editor = {M. Platt and A. Ghazanfar},
   Year = {2012},
   Key = {fds201331}
}

@misc{fds201329,
   Author = {D. Schmitt},
   Title = {Translating Primate Locomotor Biomechanical Variables from
             the Laboratory to the Field},
   Pages = {7 - 28},
   Booktitle = {Primate Locomotion: Linking in-situ and ex-situ
             Research},
   Publisher = {Springer},
   Address = {New York},
   Editor = {KD D'Auot and E. Vereecke},
   Year = {2010},
   ISBN = {1441914196},
   Key = {fds201329}
}

@misc{fds44897,
   Author = {P. Lemelin and D. Schmitt},
   Title = {The origins of grasping and locomotor adaptations in
             primates: Comparative and experimental approaches using an
             opossum model},
   Booktitle = {Primate Origins},
   Publisher = {Kluwer},
   Editor = {M. Dagosto and M. Ravosa},
   Year = {2006},
   Key = {fds44897}
}

@misc{fds44934,
   Author = {Wall, C.E. and Schmitt, D. and Vinyard, C.J. and Hylander,
             W.L.},
   Title = {Correlation between transverse mandibular movements and
             masseter muscle activity during chewing in Papio
             anubis.},
   Pages = {277-282},
   Booktitle = {Dental Anthropology 2001},
   Publisher = {Sheffield Academic Press},
   Editor = {A. Brook},
   Year = {2005},
   Key = {fds44934}
}

@misc{fds44933,
   Author = {Gruss, L. T. and Schmitt, D.},
   Title = {Bipedalism in Homo Ergaster: An experimental study of the
             effects of tibial proportions on locomotor biomechanics. In:
             (J Meldrum and C. Hilton eds.) From Biped to Strider: The
             emergence of modern human walking, running, and resource
             transport.},
   Booktitle = {From Biped to Strider: The emergence of modern human
             walking, running, and resource transport.},
   Publisher = {Kluwer},
   Editor = {C. Hilton and J. Meldrum},
   Year = {2004},
   Key = {fds44933}
}

@misc{fds44932,
   Author = {Churchill, S.E. and Schmitt, D.},
   Title = {Biomechanics in paleoanthropology: engineering and
             experimental approaches to the investigation of behavioral
             evolution in the genus Homo.},
   Booktitle = {: New Perspectives in Primate Evolution and
             Behavior.},
   Publisher = {Linnaean Society},
   Editor = {C. Harcourt and R. Crompton},
   Year = {2003},
   Key = {fds44932}
}


%% Papers Published   
@article{fds342136,
   Author = {Granatosky, MC and Schmitt, D},
   Title = {The mechanical origins of arm-swinging},
   Journal = {Journal of Human Evolution},
   Volume = {130},
   Pages = {61-71},
   Year = {2019},
   Month = {May},
   url = {http://dx.doi.org/10.1016/j.jhevol.2019.02.001},
   Abstract = {© 2019 Elsevier Ltd Arm-swinging is a locomotor mode
             observed only in primates, in which the hindlimbs no longer
             have a weight bearing function and the forelimbs must propel
             the body forward and support the entirety of the animal's
             mass. It has been suggested that the evolution of
             arm-swinging was preceded by a shift to inverted quadrupedal
             walking for purposes of feeding and balance, yet little is
             known about the mechanics of limb use during inverted
             quadrupedal walking. In this study, we test whether the
             mechanics of inverted quadrupedal walking make sense as
             precursors to arm-swinging and whether there are fundamental
             differences in inverted quadrupedal walking in primates
             compared to non-primate mammals that would explain the
             evolution of arm-swinging in primates only. Based on kinetic
             limb-loading data collected during inverted quadrupedal
             walking in primates (seven species) and non-primate mammals
             (three species), we observe that in primates the forelimb
             serves as the primary propulsive and weight bearing limb.
             Additionally, heavier individuals tend to support a greater
             distribution of body weight on their forelimbs than lighter
             ones. These kinetic patterns are not observed in non-primate
             mammals. Based on these findings, we propose that the
             ability to adopt arm-swinging is fairly simple for
             relatively large-bodied primates and merely requires the
             animal to release its grasping foot from the substrate. This
             study fills an important gap concerning the origins of
             arm-swinging and illuminates previously unknown patterns of
             primate locomotor evolution.},
   Doi = {10.1016/j.jhevol.2019.02.001},
   Key = {fds342136}
}

@article{fds341872,
   Author = {Miller, CE and Johnson, LE and Pinkard, H and Lemelin, P and Schmitt,
             D},
   Title = {Limb phase flexibility in walking: A test case in the
             squirrel monkey (Saimiri sciureus)},
   Journal = {Frontiers in Zoology},
   Volume = {16},
   Number = {1},
   Year = {2019},
   Month = {February},
   url = {http://dx.doi.org/10.1186/s12983-019-0299-8},
   Abstract = {© 2019 The Author(s). Background: Previous analyses of
             factors influencing footfall timings and gait selection in
             quadrupeds have focused on the implications for energetic
             cost or gait mechanics separately. Here we present a model
             for symmetrical walking gaits in quadrupedal mammals that
             combines both factors, and aims to predict the substrate
             contexts in which animals will select certain ranges of
             footfall timings that (1) minimize energetic cost, (2)
             minimize rolling and pitching moments, or (3) balance the
             two. We hypothesize that energy recovery will be a priority
             on all surfaces, and will be the dominant factor determining
             footfall timings on flat, ground-like surfaces. The ability
             to resist pitch and roll, however, will play a larger role
             in determining footfall choice on narrower and more complex
             branch-like substrates. As a preliminary test of the
             expectations of the model, we collected sample data on
             footfall timings in a primate with relatively high
             flexibility in footfall timings-the squirrel monkey (Saimiri
             sciureus)-walking on a flat surface, straight pole, and a
             pole with laterally-projecting branches to simulate
             simplified ground and branch substrates. We compare limb
             phase values on these supports to the expectations of the
             model. Results: As predicted, walking steps on the flat
             surface tended towards limb phase values that promote energy
             exchange. Both pole substrates induced limb phase values
             predicted to favor reduced pitching and rolling moments.
             Conclusions: These data provide novel insight into the ways
             in which animals may choose to adjust their behavior in
             response to movement on flat versus complex substrates and
             the competing selective factors that influence footfall
             timing in mammals. These data further suggest a pathway for
             future investigations using this perspective.},
   Doi = {10.1186/s12983-019-0299-8},
   Key = {fds341872}
}

@article{fds341494,
   Author = {Miller, CE and Pinkard, H and Johnson, LE and Schmitt,
             D},
   Title = {Pitch control and speed limitation during overground
             deceleration in lemurid primates.},
   Journal = {Journal of Morphology},
   Volume = {280},
   Number = {2},
   Pages = {300-306},
   Year = {2019},
   Month = {February},
   url = {http://dx.doi.org/10.1002/jmor.20944},
   Abstract = {An animal's fitness is influenced by the ability to move
             safely through its environment. Recent models have shown
             that aspects of body geometry, for example, limb length and
             center of mass (COM) position, appear to set limits for
             pitch control in cursorial quadrupeds. Models of pitch
             control predict that the body shape of these and certain
             other primates, with short forelimbs and posteriorly
             positioned COM, should allow them to decelerate rapidly
             while minimizing the risk of pitching forward. We chose to
             test these models in two non-cursorial lemurs: Lemur catta,
             the highly terrestrial ring-tailed lemur, and Eulemur
             fulvus, the highly arboreal brown lemur. We modeled the
             effects of changes in limb length and COM position on
             maximum decelerative potential for both species, as well as
             collecting data on maximal decelerations across whole
             strides. In both species, maximum measured decelerations
             fell below the range of pitch-limited deceleration values
             predicted by the geometric model, with the ring-tailed lemur
             approaching its pitch limit more closely. Both lemurs showed
             decelerative potential equivalent to or higher than horses,
             the only comparative model currently available. These data
             reinforce the hypothesis that a relatively simple model of
             body geometry can predict aspects of maximum performance in
             animals. In this case, it appears that the body geometry of
             primates is skewed toward avoiding forward pitch in maximal
             decelerations.},
   Doi = {10.1002/jmor.20944},
   Key = {fds341494}
}

@article{fds341495,
   Author = {Granatosky, MC and Schmitt, D and Hanna, J},
   Title = {Comparison of spatiotemporal gait characteristics between
             vertical climbing and horizontal walking in
             primates.},
   Journal = {The Journal of Experimental Biology},
   Volume = {222},
   Number = {Pt 2},
   Year = {2019},
   Month = {January},
   url = {http://dx.doi.org/10.1242/jeb.185702},
   Abstract = {During quadrupedal walking, most primates utilize
             diagonal-sequence diagonal-couplet gaits, large limb
             excursions and hindlimb-biased limb loading. These gait
             characteristics are thought to be basal to primates, but the
             selective pressure underlying these gait changes remains
             unknown. Some researchers have examined these
             characteristics during vertical climbing and propose that
             primate quadrupedal gait characteristics may have arisen due
             to the mechanical challenges of moving on vertical supports.
             Unfortunately, these studies are usually limited in scope
             and do not account for varying strategies based on body size
             or phylogeny. Here, we test the hypothesis that the
             spatiotemporal gait characteristics that are used during
             horizontal walking in primates are also present during
             vertical climbing irrespective of body size and phylogeny.
             We examined footfall patterns, diagonality, speed and stride
             length in eight species of primates across a range of body
             masses. We found that, during vertical climbing, primates
             slow down, keep more limbs in contact with the substrate at
             any one time, and increase the frequency of lateral-sequence
             gaits compared with horizontal walking. Taken together,
             these characteristics are assumed to increase stability
             during locomotion. Phylogenetic relatedness and body size
             differences have little influence on locomotor patterns
             observed across species. These data reject the idea that the
             suite of spatiotemporal gait features observed in primates
             during horizontal walking are in some way evolutionarily
             linked to selective pressures associated with mechanical
             requirements of vertical climbing. These results also
             highlight the importance of behavioral flexibility for
             negotiating the challenges of locomotion in an arboreal
             environment.},
   Doi = {10.1242/jeb.185702},
   Key = {fds341495}
}

@article{fds338039,
   Author = {Fabre, A-C and Granatosky, MC and Hanna, JB and Schmitt,
             D},
   Title = {Do forelimb shape and peak forces co-vary in
             strepsirrhines?},
   Journal = {American Journal of Physical Anthropology},
   Volume = {167},
   Number = {3},
   Pages = {602-614},
   Year = {2018},
   Month = {November},
   url = {http://dx.doi.org/10.1002/ajpa.23688},
   Abstract = {OBJECTIVES:In this study, we explore whether ground reaction
             forces recorded during horizontal walking co-vary with the
             shape of the long bones of the forelimb in strepsirrhines.
             To do so, we quantify (1) the shape of the shaft and
             articular surfaces of each long bone of the forelimb, (2)
             the peak vertical, mediolateral, and horizontal ground
             reaction forces applied by the forelimb during arboreal
             locomotion, and (3) the relationship between the shape of
             the forelimb and peak forces. MATERIALS AND
             METHODS:Geometric morphometric approaches were used to
             quantify the shape of the bones. Kinetic data were collected
             during horizontal arboreal walking in eight species of
             strepsirrhines that show variation in habitual substrate use
             and morphology of the forelimb. These data were then used to
             explore the links between locomotor behavior, morphology,
             and mechanics using co-variation analyses in a phylogenetic
             framework. RESULTS:Our results show significant differences
             between slow quadrupedal climbers (lorises), vertical
             clinger and leapers (sifaka), and active arboreal quadrupeds
             (ring-tailed lemur, ruffed lemur) in both ground reaction
             forces and the shape of the long bones of the forelimb, with
             the propulsive and medially directed peak forces having the
             highest impact on the shape of the humerus. Co-variation
             between long bone shape and ground reaction forces was
             detected in both the humerus and ulna even when accounting
             for differences in body mass. DISCUSSION:These results
             demonstrate the importance of considering limb-loading
             beyond just peak vertical force, or substrate reaction
             force. A re-evaluation of osseous morphology and functional
             interpretations is necessary in light of these
             findings.},
   Doi = {10.1002/ajpa.23688},
   Key = {fds338039}
}

@article{fds337047,
   Author = {Snyder, ML and Schmitt, D},
   Title = {Effects of aging on the biomechanics of Coquerel's sifaka
             (Propithecus coquereli): Evidence of robustness to
             senescence.},
   Journal = {Experimental Gerontology},
   Volume = {111},
   Pages = {235-240},
   Publisher = {Elsevier BV},
   Year = {2018},
   Month = {October},
   url = {http://dx.doi.org/10.1016/j.exger.2018.07.019},
   Abstract = {It is well-known that as humans age they experience
             significant changes in gait including reduction in velocity
             and ground reaction forces and changes in leg mechanics.
             Progressive changes in gait can lead to disability and
             frailty, defined as an inability to carry out activities of
             daily living. This topic is relevant to basic understanding
             of the aging process and for clinical intervention. As such,
             studies of frailty can benefit from nonhuman animal models,
             yet little is known about gait frailty in nonhuman primates.
             This study examines a nonhuman primate model to evaluate its
             relevance to understanding human aging processes. To test
             the null hypothesis that age-related changes in joint
             function and gait do occur in primate models in a similar
             fashion to humans, a detailed gait analysis, including
             velocity, footfall timings, and vertical ground reaction
             forces, on bipedal locomotion was performed in Coquerel's
             sifaka (Propithecus coquereli), ranging in age from
             5 years to 24 years. None of the spatiotemporal or
             kinetic gait variables measured was significantly correlated
             with age alone. There was a slight but significant reduction
             in locomotor velocity when animals were grouped into "young"
             and "old" categories. These data show that aging P.
             coquereli experience only subtle age-related changes, that
             were not nearly as extensive as reported in humans. This
             lack of change suggests that unlike humans, lemurs maintain
             gait competency at high levels, possibly because these
             animals maintain reproductive capacity close to their age of
             death and that frailty may be selected against, since gait
             disability would result in injury and death that would
             preclude independent living. Although nonhuman primates
             should experience age-related senescence, their locomotor
             performance should remain robust throughout their lifetimes,
             which raises questions about the use of primate models of
             gait disability, an area that deserves further
             investigation.},
   Doi = {10.1016/j.exger.2018.07.019},
   Key = {fds337047}
}

@article{fds337048,
   Author = {Hughes-Oliver, CN and Srinivasan, D and Schmitt, D and Queen,
             RM},
   Title = {Gender and limb differences in temporal gait parameters and
             gait variability in ankle osteoarthritis.},
   Journal = {Gait & Posture},
   Volume = {65},
   Pages = {228-233},
   Year = {2018},
   Month = {September},
   url = {http://dx.doi.org/10.1016/j.gaitpost.2018.07.180},
   Abstract = {BACKGROUND:The effects of ankle osteoarthritis on gait are
             noticeable in the clinic, but are difficult to quantify and
             score without detailed kinematic and kinetic analysis.
             Evaluationof temporal gait parameters and gait variability
             is a potential alternative. RESEARCH QUESTION:This study
             aimed to determine associations between limb and gender with
             temporal gait parameters and gait variability in ankle OA
             patients to evaluate the utility of these parameters for
             gait assessment in a clinical setting. METHODS:Following
             informed consent, 242 end-stage unilateral ankle OA patients
             walked at self-selected speed across force plates. Means and
             stride-to-stride standard deviations (SD) of stride, swing,
             stance, and double support times were determined for each
             patient. Limb x Gender ANCOVA models co-varying for walking
             speed were run for swing and stance times, while stride and
             double support times were only compared between genders.
             Statistical analysis was performed in SPSS (α = 0.05).
             RESULTS:Walking speed affected all measures of interest.
             After adjusting for walking speed, mean stride time, stride
             time SD, and stance time SD were 3.5%, 67% and 29% higher
             among women than men (p = 0.002, 0.035 and 0.02
             respectively). Swing time was 12% higher and stance time was
             6% lower on the affected side compared to the unaffected
             side (p < 0.001 for both). SIGNIFICANCE:Women have
             longer stride times and higher variability, which may
             indicate higher fall risk. Both genders minimized loading on
             the affected limb by increasing swing time and reducing
             stance time on the affected side. Simple, easy to record
             temporal gait patterns can provide useful insight into gait
             abnormalities in patients with ankle OA.},
   Doi = {10.1016/j.gaitpost.2018.07.180},
   Key = {fds337048}
}

@article{fds332803,
   Author = {Granatosky, MC and Fitzsimons, A and Zeininger, A and Schmitt,
             D},
   Title = {Mechanisms for the functional differentiation of the
             propulsive and braking roles of the forelimbs and hindlimbs
             during quadrupedal walking in primates and
             felines.},
   Journal = {The Journal of Experimental Biology},
   Volume = {221},
   Number = {Pt 2},
   Year = {2018},
   Month = {January},
   url = {http://dx.doi.org/10.1242/jeb.162917},
   Abstract = {During quadrupedal walking in most animals, the forelimbs
             play a net braking role, whereas the hindlimbs are net
             propulsive. However, the mechanism by which this
             differentiation occurs remains unclear. Here, we test two
             models to explain this pattern using primates and felines:
             (1) the horizontal strut effect (in which limbs are modeled
             as independent struts), and (2) the linked strut model (in
             which limbs are modeled as linked struts with a center of
             mass in between). Video recordings were used to determine
             point of contact, timing of mid-stance, and limb
             protraction/retraction duration. Single-limb forces were
             used to calculate contact time, impulses and the proportion
             of the stride at which the braking-to-propulsive transition
             (BP) occurred for each limb. We found no association between
             the occurrence of the BP and mid-stance, little influence of
             protraction and retraction duration on the
             braking-propulsive function of a limb, and a causative
             relationship between vertical force distribution between
             limbs and the patterns of horizontal forces. These findings
             reject the horizontal strut effect, and provide some support
             for the linked strut model, although predictions were not
             perfectly matched. We suggest that the position of the
             center of mass relative to limb contact points is a very
             important, but not the only, factor driving functional
             differentiation of the braking and propulsive roles of the
             limbs in quadrupeds. It was also found that primates have
             greater differences in horizontal impulse between their
             limbs compared with felines, a pattern that may reflect a
             fundamental arboreal adaptation in primates.},
   Doi = {10.1242/jeb.162917},
   Key = {fds332803}
}

@article{fds329281,
   Author = {Zeininger, A and Schmitt, D and Jensen, JL and Shapiro,
             LJ},
   Title = {Ontogenetic changes in foot strike pattern and calcaneal
             loading during walking in young children.},
   Journal = {Gait & Posture},
   Volume = {59},
   Pages = {18-22},
   Year = {2018},
   Month = {January},
   url = {http://dx.doi.org/10.1016/j.gaitpost.2017.09.027},
   Abstract = {The assumption that the morphology of the human calcaneus
             reflects high and cyclical impact forces at heel strike
             during adult human walking has never been experimentally
             tested. Since a walking step with a heel strike is an
             emergent behavior in children, an ontogenetic study provides
             a natural experiment to begin testing the relationship
             between the mechanics of heel strike and calcaneal anatomy.
             This study examined the ground reaction forces (GRFs) of
             stepping in children to determine the location of the center
             of pressure (COP) relative to the calcaneus and the
             orientation and magnitude of ground reaction forces during
             foot contact. Three-dimensional kinematic and kinetic data
             were analyzed for 18 children ranging in age from 11.5 to
             43.1 months. Early steppers used a flat foot contact (FFC)
             and experienced relatively high vertical and resultant GRFs
             with COP often anterior to the calcaneus. More experienced
             walkers used an initial heel contact (IHC) in which GRFs
             were significantly lower but the center of pressure remained
             under the heel a greater proportion of time. Thus, during
             FFC the foot experienced higher loading, but the heel itself
             was relatively wider and the load was distributed more
             evenly. In IHC walkers load was concentrated on the anterior
             calcaneus and a narrower heel, suggesting a need for
             increased calcaneal robusticity during development to
             mitigate injury. These results provide new insight into foot
             loading outside of typical mature contact patterns, inform
             structure-function relationships during development, and
             illuminate potential causes of heel injury in young
             walkers.},
   Doi = {10.1016/j.gaitpost.2017.09.027},
   Key = {fds329281}
}

@article{fds329280,
   Author = {Queen, RM and Franck, CT and Schmitt, D and Adams,
             SB},
   Title = {Are There Differences in Gait Mechanics in Patients With A
             Fixed Versus Mobile Bearing Total Ankle Arthroplasty? A
             Randomized Trial.},
   Journal = {Clinical Orthopaedics and Related Research®},
   Volume = {475},
   Number = {10},
   Pages = {2599-2606},
   Year = {2017},
   Month = {October},
   url = {http://dx.doi.org/10.1007/s11999-017-5405-7},
   Abstract = {BACKGROUND:Total ankle arthroplasty (TAA) is an alternative
             to arthrodesis, but no randomized trial has examined whether
             a fixed bearing or mobile bearing implant provides improved
             gait mechanics. QUESTIONS/PURPOSES:We wished to determine if
             fixed- or mobile-bearing TAA results in a larger improvement
             in pain scores and gait mechanics from before surgery to
             1 year after surgery, and to quantify differences in
             outcomes using statistical analysis and report the
             standardized effect sizes for such comparisons.
             METHODS:Patients with end-stage ankle arthritis who were
             scheduled for TAA between November 2011 and June 2013
             (n = 40; 16 men, 24 women; average age, 63 years; age
             range, 35-81 years) were prospectively recruited for this
             study from a single foot and ankle orthopaedic clinic.
             During this period, 185 patients underwent TAA, with 144
             being eligible to participate in this study. Patients were
             eligible to participate if they were able to meet all study
             inclusion criteria, which were: no previous diagnosis of
             rheumatoid arthritis, a contralateral TAA, bilateral ankle
             arthritis, previous revision TAA, an ankle fusion revision,
             or able to walk without the use of an assistive device,
             weight less than 250 pounds (114 kg), a sagittal or coronal
             plane deformity less than 15°, no presence of avascular
             necrosis of the distal tibia, no current neuropathy, age
             older than 35 years, no history of a talar neck fracture,
             or an avascular talus. Of the 144 eligible patients, 40
             consented to participate in our randomized trial. These 40
             patients were randomly assigned to either the fixed
             (n = 20) or mobile bearing implant group (n = 20).
             Walking speed, bilateral peak dorsiflexion angle, peak
             plantar flexion angle, sagittal plane ankle ROM, peak ankle
             inversion angle, peak plantar flexion moment, peak plantar
             flexion power during stance, peak weight acceptance, and
             propulsive vertical ground reaction force were analyzed
             during seven self-selected speed level walking trials for 33
             participants using an eight-camera motion analysis system
             and four force plates. Seven patients were not included in
             the analysis owing to cancelled surgery (one from each
             group) and five were lost to followup (four with fixed
             bearing and one with mobile bearing implants). A series of
             effect-size calculations and two-sample t-tests comparing
             postoperative and preoperative increases in outcome
             variables between implant types were used to determine the
             differences in the magnitude of improvement between the two
             patient cohorts from before surgery to 1 year after
             surgery. The sample size in this study enabled us to detect
             a standardized shift of 1.01 SDs between group means with
             80% power and a type I error rate of 5% for all outcome
             variables in the study. RESULTS:This randomized trial did
             not reveal any differences in outcomes between the two
             implant types under study at the sample size collected. In
             addition to these results, effect size analysis suggests
             that changes in outcome differ between implant types by less
             than 1 SD. Detection of the largest change score or observed
             effect (propulsive vertical ground reaction force [Fixed:
             0.1 ± 0.1; 0.0-1.0; Mobile: 0.0 ± 0.1; 0.0-0.0;
             p = 0.0.051]) in this study would require a future trial
             to enroll 66 patients. However, the smallest change score or
             observed effect (walking speed [Fixed: 0.2 ± 0.3;
             0.1-0.4; Mobile: 0.2 ± 0.3; 0.0-0.3; p = 0.742])
             requires a sample size of 2336 to detect a significant
             difference with 80% power at the observed effect sizes.
             CONCLUSIONS:To our knowledge, this is the first randomized
             study to report the observed effect size comparing
             improvements in outcome measures between fixed and mobile
             bearing implant types. This study was statistically powered
             to detect large effects and descriptively analyze observed
             effect sizes. Based on our results there were no
             statistically or clinically meaningful differences between
             the fixed and mobile bearing implants when examining gait
             mechanics and pain 1 year after TAA. LEVEL OF
             EVIDENCE:Level II, therapeutic study.},
   Doi = {10.1007/s11999-017-5405-7},
   Key = {fds329280}
}

@article{fds328892,
   Author = {Hanna, JB and Granatosky, MC and Rana, P and Schmitt,
             D},
   Title = {The evolution of vertical climbing in primates: evidence
             from reaction forces},
   Journal = {The Journal of Experimental Biology},
   Volume = {220},
   Number = {17},
   Pages = {3039-3052},
   Year = {2017},
   Month = {September},
   url = {http://dx.doi.org/10.1242/jeb.157628},
   Doi = {10.1242/jeb.157628},
   Key = {fds328892}
}

@article{fds328893,
   Author = {Granatosky, MC and Schmitt, D},
   Title = {Forelimb and hind limb loading patterns during below branch
             quadrupedal locomotion in the two-toed sloth},
   Journal = {Journal of Zoology},
   Volume = {302},
   Number = {4},
   Pages = {271-278},
   Publisher = {WILEY},
   Year = {2017},
   Month = {August},
   url = {http://dx.doi.org/10.1111/jzo.12455},
   Abstract = {© 2017 The Zoological Society of London The living sloths
             are the most suspensory of all extant mammals, and therefore
             represent ideal models for investigating the effects that
             suspensory behaviours have on bone and joint morphology.
             While the anatomy and kinematics of sloths are well known,
             no research has reported kinetic patterns of sloth
             locomotion. This study examines peak force patterns
             generated by the two-toed sloth Choloepus didactylus during
             below branch quadrupedal walking to infer how kinetic
             patterns of sloths compare to data reported on non-human
             primates. Values for vertical, fore-aft, and mediolateral
             peak forces were collected for the forelimb and hind limb,
             and analyses between the magnitude and timing of these peaks
             were compared between forelimbs and hind limbs. Patterns and
             timing of fore-aft peak forces were similar between sloths
             and non-human primates, and were characterized by first a
             propulsive force as the limb first made contact with the
             support followed by braking force prior to lift-off.
             Similarly, both sloths and primates demonstrate a medially
             directed force bias onto the substrate during below branch
             quadrupedal locomotion, although the magnitude observed in
             sloths exceeds values reported in primates. Peak vertical
             forces applied by the forelimbs and hind limbs of sloths
             were not statistically different in magnitude from each
             other. Data from this study indicate the forelimbs and hind
             limbs of sloths are functioning similarly to each other
             during below branch quadrupedal locomotion, and that
             forelimb-biased weight support, the pattern typical of
             primates, is not a mechanical requirement of suspensory
             locomotion across all mammals. These findings provide
             important information about the mechanical necessities of
             below branch movement, and data from this study should be
             used when considering mechanical convergence among
             suspensory taxa and the interpretation of suspensory limb
             adaptations in the fossil record.},
   Doi = {10.1111/jzo.12455},
   Key = {fds328893}
}

@article{fds327238,
   Author = {Fabre, A-C and Marigó, J and Granatosky, MC and Schmitt,
             D},
   Title = {Functional associations between support use and forelimb
             shape in strepsirrhines and their relevance to inferring
             locomotor behavior in early primates.},
   Journal = {Journal of Human Evolution},
   Volume = {108},
   Pages = {11-30},
   Year = {2017},
   Month = {July},
   url = {http://dx.doi.org/10.1016/j.jhevol.2017.03.012},
   Abstract = {The evolution of primates is intimately linked to their
             initial invasion of an arboreal environment. However, moving
             and foraging in this milieu creates significant mechanical
             challenges related to the presence of substrates differing
             in their size and orientation. It is widely assumed that
             primates are behaviorally and anatomically adapted to
             movement on specific substrates, but few explicit tests of
             this relationship in an evolutionary context have been
             conducted. Without direct tests of form-function
             relationships in living primates it is impossible to
             reliably infer behavior in fossil taxa. In this study, we
             test a hypothesis of co-variation between forelimb
             morphology and the type of substrates used by
             strepsirrhines. If associations between anatomy and
             substrate use exist, these can then be applied to better
             understand limb anatomy of extinct primates. The
             co-variation between each forelimb long bone and the type of
             substrate used was studied in a phylogenetic context. Our
             results show that despite the presence of significant
             phylogenetic signal for each long bone of the forelimb,
             clear support use associations are present. A strong
             co-variation was found between the type of substrate used
             and the shape of the radius, with and without taking
             phylogeny into account, whereas co-variation was significant
             for the ulna only when taking phylogeny into account.
             Species that use a thin branch milieu show radii that are
             gracile and straight and have a distal articular shape that
             allows for a wide range of movements. In contrast, extant
             species that commonly use large supports show a relatively
             robust and curved radius with an increased surface area
             available for forearm and hand muscles in pronated posture.
             These results, especially for the radius, support the idea
             that strepsirrhine primates exhibit specific skeletal
             adaptations associated with the supports that they
             habitually move on. With these robust associations in hand
             it will be possible to explore the same variables in extinct
             early primates and primate relatives and thus improve the
             reliability of inferences concerning substrate use in early
             primates.},
   Doi = {10.1016/j.jhevol.2017.03.012},
   Key = {fds327238}
}

@article{fds325684,
   Author = {Gruss, LT and Gruss, R and Schmitt, D},
   Title = {Pelvic Breadth and Locomotor Kinematics in Human
             Evolution.},
   Journal = {Anatomical Record (Hoboken, N.J. : 2007)},
   Volume = {300},
   Number = {4},
   Pages = {739-751},
   Editor = {Rosenberg, KR and Desilva, JM},
   Year = {2017},
   Month = {April},
   url = {http://dx.doi.org/10.1002/ar.23550},
   Abstract = {A broad pelvis is characteristic of most, if not all,
             pre-modern hominins. In at least some early
             australopithecines, most notably the female Australopithecus
             afarensis specimen known as "Lucy," it is very broad and
             coupled with very short lower limbs. In 1991, Rak suggested
             that Lucy's pelvic anatomy improved locomotor efficiency by
             increasing stride length through rotation of the wide pelvis
             in the axial plane. Compared to lengthening strides by
             increasing flexion and extension at the hips, this mechanism
             could avoid potentially costly excessive vertical
             oscillations of the body's center of mass (COM). Here, we
             test this hypothesis. We examined 3D kinematics of walking
             at various speeds in 26 adult subjects to address the
             following questions: Do individuals with wider pelves take
             longer strides, and do they use a smaller degree of hip
             flexion and extension? Is pelvic rotation greater in
             individuals with shorter legs, and those with narrower
             pelves? Our results support Rak's hypothesis. Subjects with
             wider pelves do take longer strides for a given velocity,
             and for a given stride length they flex and extend their
             hips less, suggesting a smoother pathway of the COM.
             Individuals with shorter legs do use more pelvic rotation
             when walking, but pelvic breadth was not related to pelvic
             rotation. These results suggest that a broad pelvis could
             benefit any bipedal hominin, but especially a short-legged
             australopithecine such as Lucy, by improving locomotor
             efficiency, particularly when carrying an infant or
             traveling in a foraging group with individuals of varying
             sizes. Anat Rec, 300:739-751, 2017. © 2017 Wiley
             Periodicals, Inc.},
   Doi = {10.1002/ar.23550},
   Key = {fds325684}
}

@article{fds322453,
   Author = {Larsen, RJ and Jackson, WH and Schmitt, D},
   Title = {Mechanisms for regulating step length while running towards
             and over an obstacle.},
   Journal = {Human Movement Science},
   Volume = {49},
   Pages = {186-195},
   Year = {2016},
   Month = {October},
   url = {http://dx.doi.org/10.1016/j.humov.2016.07.002},
   Abstract = {The ability to run across uneven terrain with continuous
             stable movement is critical to the safety and efficiency of
             a runner. Successful step-to-step stabilization while
             running may be mediated by minor adjustments to a few key
             parameters (e.g., leg stiffness, step length, foot strike
             pattern). However, it is not known to what degree runners in
             relatively natural settings (e.g., trails, paved road,
             curbs) use the same strategies across multiple steps. This
             study investigates how three readily measurable running
             parameters - step length, foot placement, and foot strike
             pattern - are adjusted in response to encountering a typical
             urban obstacle - a sidewalk curb. Thirteen subjects were
             video-recorded as they ran at self-selected slow and fast
             paces. Runners targeted a specific distance before the curb
             for foot placement, and lengthened their step over the curb
             (p<0.0001) regardless of where the step over the curb was
             initiated. These strategies of adaptive locomotion disrupt
             step cycles temporarily, and may increase locomotor cost and
             muscle loading, but in the end assure dynamic stability and
             minimize the risk of injury over the duration of a
             run.},
   Doi = {10.1016/j.humov.2016.07.002},
   Key = {fds322453}
}

@article{fds329921,
   Author = {Burgess, ML and Schmitt, D and Zeininger, A and McFarlin, SC and Zihlman, AL and Polk, JD and Ruff, CB},
   Title = {Ontogenetic scaling of fore limb and hind limb joint posture
             and limb bone cross-sectional geometry in vervets and
             baboons.},
   Journal = {American Journal of Physical Anthropology},
   Volume = {161},
   Number = {1},
   Pages = {72-83},
   Year = {2016},
   Month = {September},
   url = {http://dx.doi.org/10.1002/ajpa.23009},
   Abstract = {Previous studies suggest that the postures habitually
             adopted by an animal influence the mechanical loading of its
             long bones. Relatively extended limb postures in larger
             animals should preferentially reduce anteroposterior (A-P)
             relative to mediolateral (M-L) bending of the limb bones and
             therefore decrease A-P/M-L rigidity. We test this hypothesis
             by examining growth-related changes in limb bone structure
             in two primate taxa that differ in ontogenetic patterns of
             joint posture.Knee and elbow angles of adult and immature
             vervets (Chlorocebus aethiops, n = 16) were compared to
             published data for baboons (Papio hamadryas ursinus,
             n = 33, Patel et al., ). Ontogenetic changes in ratios
             of A-P/M-L bending rigidity in the femur and humerus were
             compared in skeletal samples (C. aethiops, n = 28; P.
             cynocephalus, n = 39). Size changes were assessed with
             linear regression, and age group differences tested with
             ANOVA.Only the knee of baboons shows significant postural
             change, becoming more extended with age and mass. A-P/M-L
             bending rigidity of the femur decreases during ontogeny in
             immature and adult female baboons only. Trends in the
             humerus are less marked. Adult male baboons have higher
             A-P/M-L bending rigidity of the femur than females.The
             hypothesized relationship between more extended joints and
             reduced A-P/M-L bending rigidity is supported by our results
             for immature and adult female baboon hind limbs, and the
             lack of significant age changes in either parameter in
             forelimbs and vervets. Adult males of both species depart
             from general ontogenetic trends, possibly due to socially
             mediated behavioral differences between sexes. Am J Phys
             Anthropol 161:72-83, 2016. © 2016 Wiley Periodicals,
             Inc.},
   Doi = {10.1002/ajpa.23009},
   Key = {fds329921}
}

@article{fds322454,
   Author = {Queen, RM and Sparling, TL and Schmitt, D},
   Title = {Hip, Knee, and Ankle Osteoarthritis Negatively Affects
             Mechanical Energy Exchange.},
   Journal = {Clinical Orthopaedics and Related Research®},
   Volume = {474},
   Number = {9},
   Pages = {2055-2063},
   Year = {2016},
   Month = {September},
   url = {http://dx.doi.org/10.1007/s11999-016-4921-1},
   Abstract = {Individuals with osteoarthritis (OA) of the lower limb find
             normal locomotion tiring compared with individuals without
             OA, possibly because OA of any lower limb joint changes limb
             mechanics and may disrupt transfer of potential and kinetic
             energy of the center of mass during walking, resulting in
             increased locomotor costs. Although recovery has been
             explored in asymptomatic individuals and in some patient
             populations, the effect of changes in these gait parameters
             on center of mass movements and mechanical work in patients
             with OA in specific joints has not been well examined. The
             results can be used to inform clinical interventions and
             rehabilitation that focus on improving energy recovery.We
             hypothesized that (1) individuals with end-stage lower
             extremity OA would exhibit a decrease in walking velocity
             compared with asymptomatic individuals and that the joint
             affected with OA would differntially influence walking
             velocity, (2) individuals with end-stage lower extremity OA
             would show decreased energy recovery compared with
             asymptomatic individuals and that individuals with end-stage
             hip and ankle OA would have greater reductions in recovery
             than would individuals with end-stage knee OA owing to
             restrictions in hip and ankle motion, and (3) that
             differences in the amplitude and congruity of the center of
             mass would explain the differences in energy recovery that
             are observed in each population.Ground reaction forces at a
             range of self-selected walking speeds were collected from
             individuals with end-stage radiographic hip OA (n = 27; 14
             males, 13 females; average age, 55.6 years; range, 41-70
             years), knee OA (n = 20; seven males, 13 females; average
             age, 61.7 years; range, 49-74 years), ankle OA (n = 30; 14
             males, 16 females; average age, 57 years; range, 45-70
             years), and asymptomatic individuals (n = 13; eight males,
             five females; average age, 49.8 years; range, 41-67 years).
             Participants were all patients with end-stage OA who were
             scheduled to have joint replacement surgery within 4 weeks
             of testing. All patients were identified by the orthopaedic
             surgeon as having end-stage radiographic disease and to be a
             candidate for joint replacement surgery. Patients were
             excluded if they had pain at any other lower extremity
             joint, previous joint replacement surgery, or needed to use
             an assistive device for ambulation. Patients were enrolled
             if they met the study inclusion criteria. Our study was
             comparative and cohorts could be compared with each other,
             however, the asymptomatic group served to verify our methods
             and provided a recovery standard with which we could compare
             our patients. Potential and kinetic energy relationships (%
             congruity) and energy exchange (% recovery) were calculated.
             Linear regressions were used to examine the effect of
             congruity and amplitude of energy fluctuations and walking
             velocity on % recovery. Analysis of covariance was used to
             compare energy recovery between groups.The results of this
             study support our hypothesis that individuals with OA walk
             at a slower velocity than asymptomatic individuals (1.4 ±
             0.2 m/second, 1.2-1.5 m/second) and that the joint affected
             by OA also affects walking velocity (p < 0.0001). The cohort
             with ankle OA (0.9 ± 0.2 m/second, 0.77-0.94 m/second)
             walked at a slower speed relative to the cohort with hip OA
             (1.1 ± 0.2 m/second, 0.96-1.1 m/second; p = 0.002).
             However, when comparing the cohorts with ankle and knee OA
             (0.9 ± 0.2 m/second, 0.77-0.94 m/second) there was no
             difference in walking speed (p = 0.16) and the same was true
             when comparing the cohorts with knee and hip OA (p = 0.14).
             Differences in energy recovery existed when comparing the OA
             cohorts with the asymptomatic cohort and when examining
             differences between the OA cohorts. After adjusting for
             walking speeds these results showed that asymptomatic
             individuals (65% ± 3%, 63%-67%) had greater recovery than
             individuals with hip OA (54% ± 10%, 50%-58%; p = 0.014) and
             ankle OA (47% ± 13%, 40%-52%; p = 0.002) but were not
             different compared with individuals with knee OA (57% ±
             10%, 53%-62%; p = 0.762). When speed was accounted for, 80%
             of the variation in recovery not attributable to speed was
             explained by congruity with only 10% being explained by
             amplitude.OA in the hip, knee, or ankle reduces effective
             exchange of potential and kinetic energy, potentially
             increasing the muscular work required to control movements
             of the center of mass.The fatigue and limited physical
             activity reported in patients with lower extremity OA could
             be associated with increased mechanical work of the center
             of mass. Focused gait retraining potentially could improve
             walking mechanics and decrease fatigue in these
             patients.},
   Doi = {10.1007/s11999-016-4921-1},
   Key = {fds322454}
}

@article{fds322455,
   Author = {Granatosky, MC and Tripp, CH and Fabre, A-C and Schmitt,
             D},
   Title = {Patterns of quadrupedal locomotion in a vertical clinging
             and leaping primate (Propithecus coquereli) with
             implications for understanding the functional demands of
             primate quadrupedal locomotion.},
   Journal = {American Journal of Physical Anthropology},
   Volume = {160},
   Number = {4},
   Pages = {644-652},
   Year = {2016},
   Month = {August},
   url = {http://dx.doi.org/10.1002/ajpa.22991},
   Abstract = {OBJECTIVES:Many primates exhibit a suite of characteristics
             that distinguish their quadrupedal gaits from non-primate
             mammals including the use of a diagonal sequence gait, a
             relatively protracted humerus at touchdown, and relatively
             high peak vertical forces on the hindlimbs compared to the
             forelimbs. These characteristics are thought to have evolved
             together in early, small-bodied primates possibly in
             response to the mechanical demands of navigating and
             foraging in a complex arboreal environment. It remains
             unclear, however, whether primates that employ
             quadrupedalism only rarely demonstrate the common primate
             pattern of quadrupedalism or instead use the common
             non-primate pattern or an entirely different mechanical
             pattern from either group. MATERIALS AND METHODS:This study
             compared the kinematics and kinetics of two habitually
             quadrupedal primates (Lemur catta and Varecia variegata) to
             those of a dedicated vertical clinger and leaper
             (Propithecus coquereli) during bouts of quadrupedal walking.
             RESULTS:All three species employed diagonal sequence gaits
             almost exclusively, displayed similar degrees of humeral
             protraction, and exhibited lower vertical peak forces in the
             forelimbs compared to the hindlimb. DISCUSSION:From the data
             in this study, it is possible to reject the idea that P.
             coquereli uses a non-primate pattern of quadrupedal walking
             mechanics. Nor do they use an entirely different mechanical
             pattern from either most primates or most non-primates
             during quadrupedal locomotion. These findings provide
             support for the idea that this suite of characteristics is
             adaptive for the challenges of arboreal locomotion in
             primates and that these features of primate locomotion may
             be basal to the order or evolved independently in multiple
             lineages including indriids. Am J Phys Anthropol
             160:644-652, 2016. © 2016 Wiley Periodicals,
             Inc.},
   Doi = {10.1002/ajpa.22991},
   Key = {fds322455}
}

@article{fds322456,
   Author = {Granatosky, MC and Tripp, CH and Schmitt, D},
   Title = {Gait kinetics of above- and below-branch quadrupedal
             locomotion in lemurid primates.},
   Journal = {The Journal of Experimental Biology},
   Volume = {219},
   Number = {Pt 1},
   Pages = {53-63},
   Year = {2016},
   Month = {January},
   url = {http://dx.doi.org/10.1242/jeb.120840},
   Abstract = {For primates and other mammals moving on relatively thin
             branches, the ability to effectively adopt both above- and
             below-branch locomotion is seen as critical for successful
             arboreal locomotion, and has been considered an important
             step prior to the evolution of specialized suspensory
             locomotion within our Order. Yet, little information exists
             on the ways in which limb mechanics change when animals
             shift from above- to below-branch quadrupedal locomotion.
             This study tested the hypothesis that vertical force
             magnitude and distribution do not vary between locomotor
             modes, but that the propulsive and braking roles of the
             forelimb change when animals shift from above- to
             below-branch quadrupedal locomotion. We collected kinetic
             data on two lemur species (Varecia variegata and Lemur
             catta) walking above and below an instrumented arboreal
             runway. Values for peak vertical, braking and propulsive
             forces as well as horizontal impulses were collected for
             each limb. When walking below branch, both species
             demonstrated a significant shift in limb kinetics compared
             with above-branch movement. The forelimb became both the
             primary weight-bearing limb and propulsive organ, while the
             hindlimb reduced its weight-bearing role and became the
             primary braking limb. This shift in force distribution
             represents a shift toward mechanics associated with bimanual
             suspensory locomotion, a locomotor mode unusual to primates
             and central to human evolution. The ability to make this
             change is not accompanied by significant anatomical changes,
             and thus likely represents an underlying mechanical
             flexibility present in most primates.},
   Doi = {10.1242/jeb.120840},
   Key = {fds322456}
}

@article{fds290832,
   Author = {Johnson, LE and Hanna, J and Schmitt, D},
   Title = {Single-limb force data for two lemur species while
             vertically clinging.},
   Journal = {American Journal of Physical Anthropology},
   Volume = {158},
   Number = {3},
   Pages = {463-474},
   Year = {2015},
   Month = {November},
   ISSN = {0002-9483},
   url = {http://dx.doi.org/10.1002/ajpa.22803},
   Abstract = {Vertical clinging and climbing have been integral to
             hypotheses about primate origins, yet little is known about
             how an animal with nails instead of claws resists gravity
             while on large, vertical, and cylindrical substrates. Here
             we test models of how force is applied to maintain posture,
             predicting (1) the shear component force (Fs ) at the hands
             will be higher than the feet; (2) the normal component force
             (Fn ) at the feet will be relatively high compared to the
             hands; (3) the component force resisting gravity (Fg ) at
             the feet will be relatively high compared to the hands; (4)
             species with a high frequency of vertical clinging postures
             will have low Fg at the hands due to relatively short
             forelimbs.Using a novel instrumented support, single-limb
             force data were collected during clinging postures for the
             hands and feet and compared across limbs and species for
             Propithecus verreauxi (N = 2), a habitual vertical
             clinger and leaper, and Varecia variegata (N = 3), a
             habitual above-branch arboreal quadruped.For both species,
             hand Fs were significantly higher than at the feet and Fn
             and Fg at the feet were significantly higher than at the
             hands. Between species, P. verreauxi has relatively low Fg
             at the hands and Fn at the feet than V. vareigata.These
             results support previous models and show that hindlimb
             loading dominance, characteristic of primate locomotion, is
             found during clinging behaviors and may allow the forelimbs
             to be used for foraging while clinging. These findings
             provide insight into selective pressures on force
             distribution in primates and primate locomotor
             evolution.},
   Doi = {10.1002/ajpa.22803},
   Key = {fds290832}
}

@article{fds241056,
   Author = {Schmitt, D and Vap, A and Queen, RM},
   Title = {Effect of end-stage hip, knee, and ankle osteoarthritis on
             walking mechanics.},
   Journal = {Gait & Posture},
   Volume = {42},
   Number = {3},
   Pages = {373-379},
   Year = {2015},
   Month = {September},
   ISSN = {0966-6362},
   url = {http://dx.doi.org/10.1016/j.gaitpost.2015.07.005},
   Abstract = {This study tested the hypothesis that the presence of
             isolated ankle (A-OA; N=30), knee (K-OA; N=20), or hip
             (H-OA; N=30) osteoarthritis (OA) compared to asymptomatic
             controls (N=15) would lead to mechanical changes in the
             affected joint but also in all other lower limb joints and
             gait overall. Stride length, stance and swing times, as well
             as joint angles and moments at the hip, knee, and ankle were
             derived from 3-D kinematic and kinetic data collected from
             seven self-selected speed walking trial. Values were
             compared across groups using a 1×4 ANCOVA, covarying for
             walking speed. With walking speed controlled, the results
             indicated a reduction in hip and knee extension and ankle
             plantar flexion in accordance with the joint affected. In
             addition, OA in one joint had strong effects on other
             joints. In both H-OA and K-OA groups the hip never passed
             into extension, and A-OA subjects significantly changed hip
             kinematics to compensate for lack of plantar flexion.
             Finally, OA in any joint led to lower peak vertical forces
             as well as extension and plantar flexion moments compared to
             controls. The presence of end-stage OA at various lower
             extremity joints results in compensatory gait mechanics that
             cause movement alterations throughout the lower extremity.
             This work reinforces our understanding of the complex
             interaction of joints of the lower limb and the importance
             of focusing on the mechanics of the entire lower limb when
             considering gait disability and potential interventions in
             patients with isolated OA.},
   Doi = {10.1016/j.gaitpost.2015.07.005},
   Key = {fds241056}
}

@article{fds241051,
   Author = {Rabey, KN and Li, Y and Norton, JN and Reynolds, RP and Schmitt,
             D},
   Title = {Vibrating Frequency Thresholds in Mice and Rats:
             Implications for the Effects of Vibrations on Animal
             Health.},
   Journal = {Annals of Biomedical Engineering},
   Volume = {43},
   Number = {8},
   Pages = {1957-1964},
   Year = {2015},
   Month = {August},
   ISSN = {0090-6964},
   url = {http://dx.doi.org/10.1007/s10439-014-1226-y},
   Abstract = {Vibrations in research facilities can cause complex animal
             behavioral and physiological responses that can affect
             animal health and research outcomes. The goal of this study
             was to determine the range of frequency values, where
             animals are unable to attenuate vibrations, and therefore
             may be most susceptible to their effects. Anesthetized and
             euthanized adult rats and mice were exposed to vibration
             frequencies over a wide range (0-600 Hz) and at a constant
             magnitude of 0.3 m/s(2). Euthanized animals were
             additionally exposed to vibrations at an acceleration of 1
             m/s(2). The data showed that at most frequencies rodents
             were able to attenuate vibration magnitudes, with values for
             the back-mounted accelerometer being substantially less than
             that of the table. At frequencies of 41-60 Hz mice did not
             attenuate vibration magnitude, but instead the magnitude of
             the table and animal were equal or amplified. Rats
             experienced the same pattern of non-attenuation between 31
             and 50 Hz. Once euthanized, the mice vibrated at a slightly
             more elevated frequency (up to 100 Hz). Based on these
             results, it may be prudent that in laboratory settings,
             vibrations in the ranges reported here should be accounted
             for as possible contributors to animal stress and/or
             biomechanical changes.},
   Doi = {10.1007/s10439-014-1226-y},
   Key = {fds241051}
}

@article{fds241054,
   Author = {Hanna, JB and Schmitt, D and Wright, K and Eshchar, Y and Visalberghi,
             E and Fragaszy, D},
   Title = {Kinetics of bipedal locomotion during load carrying in
             capuchin monkeys.},
   Journal = {Journal of Human Evolution},
   Volume = {85},
   Pages = {149-156},
   Publisher = {Elsevier BV},
   Year = {2015},
   Month = {August},
   ISSN = {0047-2484},
   url = {http://dx.doi.org/10.1016/j.jhevol.2015.05.006},
   Abstract = {Facultative bipedalism during load transport in nonhuman
             primates has been argued to be an important behavior
             potentially leading to the evolution of obligate, extended
             limb bipedalism. Understanding the biomechanics of such
             behavior may lead to insights about associated morphology,
             which may translate to interpretation of features in the
             fossil record. Some populations of bearded capuchin monkeys
             (Sapajus libidinosus) spontaneously carry heavy loads
             bipedally during foraging activities. This study provides
             the first data on all three components of ground reaction
             force for spontaneous bipedalism during load carriage in a
             nonhuman primate. Five individual S. libidinosus (mean body
             mass = 2.4 kg ± 0.96) were videorecorded during
             bipedalism while carrying a stone (0.93 kg) under natural
             conditions. A force plate was embedded in the path of the
             monkeys. Spatiotemporal and force data for all three
             components of the ground reaction force were recorded for 28
             steps. Capuchins exhibited a mean vertical peak force per
             total weight (Vpk) for the hindlimb of 1.19 (sd = 0.13),
             consistent with those of unloaded capuchins in the
             laboratory and for other bipedal primates, including humans.
             Vertical force records suggest that capuchins, along with
             most nonhuman primates, maintain a relatively compliant leg
             during both unloaded and loaded locomotion. Like all other
             primates, loaded capuchins maintained laterally (outward)
             directed medio-lateral forces, presumably to stabilize
             side-to-side movements of the center of mass. Medio-lateral
             forces suggest that at near-running speeds dynamic stability
             diminishes the need to generate high lateral forces.
             Vertical force traces exhibited a measurable impact spike at
             foot contact in 85% of the steps recorded. An impact spike
             is common in human walking and running but has not been
             reported in other bipedal primates. This spike in humans is
             thought to lead to bone and cartilage damage. The earliest
             biped may have experienced similar impact spikes during
             bipedal locomotion, requiring compensatory behaviors or
             anatomical features.},
   Doi = {10.1016/j.jhevol.2015.05.006},
   Key = {fds241054}
}

@article{fds241057,
   Author = {Li, Y and Rabey, KN and Schmitt, D and Norton, JN and Reynolds,
             RP},
   Title = {Characteristics of Vibration that Alter Cardiovascular
             Parameters in Mice.},
   Journal = {Journal of the American Association for Laboratory Animal
             Science : Jaalas},
   Volume = {54},
   Number = {4},
   Pages = {372-377},
   Year = {2015},
   Month = {July},
   ISSN = {1559-6109},
   Abstract = {We hypothesized that short-term exposure of mice to
             vibration within a frequency range thought to be near the
             resonant frequency range of mouse tissue and at an
             acceleration of 0 to 1 m/s(2) would alter heart rate (HR)
             and mean arterial pressure (MAP). We used radiotelemetry to
             evaluate the cardiovascular response to vibration in C57BL/6
             and CD1 male mice exposed to vertical vibration of various
             frequencies and accelerations. MAP was consistently
             increased above baseline values at an acceleration near 1
             m/s(2) and a frequency of 90 Hz in both strains, and HR was
             increased also in C57BL/6 mice. In addition, MAP increased
             at 80 Hz in individual mice of both strains. When both
             strains were analyzed together, mean MAP and HR were
             increased at 90 Hz at 1 m/s(2), and HR was increased at 80
             Hz at 1 m/s(2). No consistent change in MAP or HR occurred
             when mice were exposed to frequencies below 80 Hz or above
             90 Hz. The increase in MAP and HR occurred only when the
             mice had conscious awareness of the vibration, given that
             these changes did not occur when anesthetized mice were
             exposed to vibration. Tested vibration acceleration levels
             lower than 0.75 m/s(2) did not increase MAP or HR at 80 or
             90 Hz, suggesting that a relatively high level of vibration
             is necessary to increase these parameters. These data are
             important to establish the harmful frequencies and
             accelerations of environmental vibration that should be
             minimized or avoided in mouse facilities.},
   Key = {fds241057}
}

@article{fds241055,
   Author = {Gruss, LT and Schmitt, D},
   Title = {The evolution of the human pelvis: changing adaptations to
             bipedalism, obstetrics and thermoregulation.},
   Journal = {Philosophical Transactions of the Royal Society of London.
             Series B, Biological Sciences},
   Volume = {370},
   Number = {1663},
   Pages = {20140063},
   Year = {2015},
   Month = {March},
   ISSN = {0962-8436},
   url = {http://dx.doi.org/10.1098/rstb.2014.0063},
   Abstract = {The fossil record of the human pelvis reveals the selective
             priorities acting on hominin anatomy at different points in
             our evolutionary history, during which mechanical
             requirements for locomotion, childbirth and thermoregulation
             often conflicted. In our earliest upright ancestors,
             fundamental alterations of the pelvis compared with
             non-human primates facilitated bipedal walking. Further
             changes early in hominin evolution produced a platypelloid
             birth canal in a pelvis that was wide overall, with flaring
             ilia. This pelvic form was maintained over 3-4 Myr with only
             moderate changes in response to greater habitat diversity,
             changes in locomotor behaviour and increases in brain size.
             It was not until Homo sapiens evolved in Africa and the
             Middle East 200 000 years ago that the narrow anatomically
             modern pelvis with a more circular birth canal emerged. This
             major change appears to reflect selective pressures for
             further increases in neonatal brain size and for a narrow
             body shape associated with heat dissipation in warm
             environments. The advent of the modern birth canal, the
             shape and alignment of which require fetal rotation during
             birth, allowed the earliest members of our species to deal
             obstetrically with increases in encephalization while
             maintaining a narrow body to meet thermoregulatory demands
             and enhance locomotor performance.},
   Doi = {10.1098/rstb.2014.0063},
   Key = {fds241055}
}

@article{fds241053,
   Author = {Griffin, NL and Miller, CE and Schmitt, D and D'Août,
             K},
   Title = {Understanding the evolution of the windlass mechanism of the
             human foot from comparative anatomy: Insights, obstacles,
             and future directions.},
   Journal = {American Journal of Physical Anthropology},
   Volume = {156},
   Number = {1},
   Pages = {1-10},
   Year = {2015},
   Month = {January},
   ISSN = {0002-9483},
   url = {http://dx.doi.org/10.1002/ajpa.22636},
   Abstract = {Humans stand alone from other primates in that we propel our
             bodies forward on a relatively stiff and arched foot and do
             so by employing an anatomical arrangement of bones and
             ligaments in the foot that can operate like a "windlass."
             This is a significant evolutionary innovation, but it is
             currently unknown when during hominin evolution this
             mechanism developed and within what genera or species it
             originated. The presence of recently discovered fossils
             along with novel research in the past two decades have
             improved our understanding of foot mechanics in humans and
             other apes, making it possible to consider this question
             more fully. Here we review the main elements thought to be
             involved in the production of an effective, modern
             human-like windlass mechanism. These elements are the
             triceps surae, plantar aponeurosis, medial longitudinal
             arch, and metatarsophalangeal joints. We discuss what is
             presently known about the evolution of these features and
             the challenges associated with identifying each of these
             specific components and/or their function in living and
             extinct primates for the purpose of predicting the presence
             of the windlass mechanism in our ancestors. In some cases we
             recommend alternative pathways for inferring foot mechanics
             and for testing the hypothesis that the windlass mechanism
             evolved to increase the speed and energetic efficiency of
             bipedal gait in hominins.},
   Doi = {10.1002/ajpa.22636},
   Key = {fds241053}
}

@article{fds241052,
   Author = {Wunderlich, RE and Tongen, A and Gardiner, J and Miller, CE and Schmitt,
             D},
   Title = {Dynamics of locomotor transitions from arboreal to
             terrestrial substrates in Verreaux's sifaka (Propithecus
             verreauxi).},
   Journal = {Integrative and Comparative Biology},
   Volume = {54},
   Number = {6},
   Pages = {1148-1158},
   Year = {2014},
   Month = {December},
   ISSN = {1540-7063},
   url = {http://dx.doi.org/10.1093/icb/icu110},
   Abstract = {Most primates are able to move with equal facility on the
             ground and in trees, but most use the same quadrupedal gaits
             in both environments. A few specialized primates, however,
             use a suspensory or leaping mode of locomotion when in the
             trees but a bipedal gait while on the ground. This is a rare
             behavioral pattern among mammals, and the extent to which
             the bipedal gaits of these primates converge and are
             constrained by the anatomical and neurological adaptations
             associated with arboreal locomotion is poorly understood.
             Sifakas (Propithecus), primates living only in Madagascar,
             are highly committed vertical clingers and leapers that also
             spend a substantial amount of time on the ground. When
             moving terrestrially sifakas use a unique bipedal galloping
             gait seen in no other mammals. Little research has examined
             the mechanics of these gaits, and most of that research has
             been restricted to controlled captive conditions. The
             energetic costs associated with leaping and bipedal
             galloping are unknown. This study begins to fill that gap
             using triaxial accelerometry to characterize and compare the
             dynamics of sifakas' leaping and bipedal galloping behavior.
             As this is a relatively novel approach, the first goal of
             this article is to explore the feasibility of collecting
             such data on free-roaming animals and attempt to automate
             the identification of leaping and bipedal behavior within
             the output. The second goal is to compare the overall
             accelerations of the body and to use that as an
             approximation of aspects of energetic costs during leaping
             and bipedalism. To achieve this, a lightweight accelerometer
             was mounted on freely moving sifakas. The resulting
             acceleration profiles were processed, and sequences of leaps
             (bouts) were automatically extracted from the waveforms with
             85% accuracy. Both vector dynamic body acceleration and
             overall dynamic body acceleration (ODBA) were used to
             characterize locomotor patterns and energy expenditure
             during leaping and bipedalism. The unique kinematics of the
             gait of sifakas, and the mechanics of bouts involving a
             string of successive leaps or gallops, appear to minimize
             redirections of the center of mass as well as the number of
             acceleration peaks and ODBAs. These results suggest that
             bipedal galloping is not only a reflection of the unique
             anatomical configuration of a leaping primate, but it may
             also provide a musculoskeletal and an energetic advantage to
             sifakas. In that sense, bipedal galloping represents an
             advantageous way for sifakas to move when transitioning from
             arboreal leaping to terrestrial locomotion.},
   Doi = {10.1093/icb/icu110},
   Key = {fds241052}
}

@article{fds241058,
   Author = {Granatosky, MC and Miller, CE and Boyer, DM and Schmitt,
             D},
   Title = {Lumbar vertebral morphology of flying, gliding, and
             suspensory mammals: implications for the locomotor behavior
             of the subfossil lemurs Palaeopropithecus and
             Babakotia.},
   Journal = {Journal of Human Evolution},
   Volume = {75},
   Pages = {40-52},
   Year = {2014},
   Month = {October},
   ISSN = {0047-2484},
   url = {http://dx.doi.org/10.1016/j.jhevol.2014.06.011},
   Abstract = {Lumbar vertebral morphology has been used as an indicator of
             locomotor behavior in living and fossil mammals. Rigidity
             within the lumbar region is thought to be important for
             increasing overall axial rigidity during various forms of
             locomotion, including bridging between supports, inverted
             quadrupedalism, gliding, and flying. However, distinguishing
             between those behaviors using bony features has been
             challenging. This study used osteological characters of the
             lumbar vertebrae to attempt to develop fine-grade functional
             distinctions among different mammalian species in order to
             make more complete inferences about how the axial skeleton
             affects locomotor behavior in extant mammals. These same
             lumbar characters were measured in two extinct species for
             which locomotor behaviors are well known, the sloth lemurs
             (Palaeopropithecus and Babakotia radofilai), in order to
             further evaluate their locomotor behaviors. Results from a
             principal components analysis of seven measurements,
             determined to be functionally significant from previous
             studies, demonstrate that inverted quadrupeds in the sample
             are characterized by dorsoventrally short and
             cranio-caudally expanded spinous processes, dorsally
             oriented transverse processes, and mediolaterally short and
             dorsoventrally high vertebral bodies compared with mammals
             that are relatively pronograde, vertical clingers, or
             gliders. Antipronograde mammals, dermopterans, and
             chiropterans also exhibit these traits, but not to the same
             extent as the inverted quadrupeds. In accordance with
             previous studies, our data show that the sloth lemur
             B. radofilai groups closely with antipronograde mammals
             like lorises, while Palaeopropithecus groups with extant
             sloths. These findings suggest that Palaeopropithecus was
             engaged in inverted quadrupedalism at a high frequency,
             while B. radofilai may have engaged in a more diverse array
             of locomotor and positional behaviors. The osteological
             features used here reflect differences in lumbar mobility
             and suggest that axial rigidity is advantageous for
             suspensory locomotion and possibly flight in
             bats.},
   Doi = {10.1016/j.jhevol.2014.06.011},
   Key = {fds241058}
}

@article{fds241061,
   Author = {Sparling, TL and Schmitt, D and Miller, CE and Guilak, F and Somers, TJ and Keefe, FJ and Queen, RM},
   Title = {Energy recovery in individuals with knee
             osteoarthritis.},
   Journal = {Osteoarthritis and Cartilage},
   Volume = {22},
   Number = {6},
   Pages = {747-755},
   Year = {2014},
   Month = {June},
   ISSN = {1063-4584},
   url = {http://hdl.handle.net/10161/8901 Duke open
             access},
   Abstract = {Pathological gaits have been shown to limit transfer between
             potential (PE) and kinetic (KE) energy during walking, which
             can increase locomotor costs. The purpose of this study was
             to examine whether energy exchange would be limited in
             people with knee osteoarthritis (OA).Ground reaction forces
             during walking were collected from 93 subjects with
             symptomatic knee OA (self-selected and fast speeds) and 13
             healthy controls (self-selected speed) and used to calculate
             their center of mass (COM) movements, PE and KE
             relationships, and energy recovery during a stride.
             Correlations and linear regressions examined the impact of
             energy fluctuation phase and amplitude, walking velocity,
             body mass, self-reported pain, and radiographic severity on
             recovery. Paired t-tests were run to compare energy recovery
             between cohorts.Symptomatic knee OA subjects displayed lower
             energetic recovery during self-selected walking speeds than
             healthy controls (P = 0.0018). PE and KE phase
             relationships explained the majority (66%) of variance in
             recovery. Recovery had a complex relationship with velocity
             and its change across speeds was significantly influenced by
             the self-selected walking speed of each subject. Neither
             radiographic OA scores nor subject self-reported measures
             demonstrated any relationship with energy recovery.Knee OA
             reduces effective exchange of PE and KE, potentially
             increasing the muscular work required to control movements
             of the COM. Gait retraining may return subjects to more
             normal patterns of energy exchange and allow them to reduce
             fatigue.},
   Doi = {10.1016/j.joca.2014.04.004},
   Key = {fds241061}
}

@article{fds241059,
   Author = {McNeill, JN and Wu, C-L and Rabey, KN and Schmitt, D and Guilak,
             F},
   Title = {Life-long caloric restriction does not alter the severity of
             age-related osteoarthritis.},
   Journal = {Age (Dordrecht, Netherlands)},
   Volume = {36},
   Number = {4},
   Pages = {9669},
   Year = {2014},
   Month = {January},
   ISSN = {0161-9152},
   url = {http://dx.doi.org/10.1007/s11357-014-9669-5},
   Abstract = {Chronic adipose tissue inflammation and its associated
             adipokines have been linked to the development of
             osteoarthritis (OA). It has been shown that caloric
             restriction may decrease body mass index and adiposity. The
             objectives of this study were to investigate the effect of
             lifelong caloric restriction on bone morphology, joint
             inflammation, and spontaneously occurring OA development in
             aged mice. C57BL/NIA mice were fed either a
             calorie-restricted (CR) or ad libitum (AL) diet starting at
             14 weeks of age. All mice were sacrificed at 24 months of
             age. Adipose tissue and knee joints were then harvested.
             Bone parameters of the joints were analyzed by micro-CT. OA
             and joint synovitis were determined using histology and
             semiquantitative analysis. Lifelong caloric restriction did
             not alter the severity of OA development in C57BL/NIA aged
             mice, and there was no difference in the total joint Mankin
             score between CR and AL groups (p = 0.99). Mice also
             exhibited similar levels of synovitis (p = 0.54). The bone
             mineral density of the femur and the tibia was comparable
             between the groups with a small increase in cancellous bone
             volume fraction in the lateral femoral condyle of the CR
             group compared with the AL group. Lifelong caloric
             restriction did not alter the incidence of OA or joint
             synovitis in C57BL/NIA mice, indicating that a reduction of
             caloric intake alone was not sufficient to prevent
             spontaneous age-related OA. Nonetheless, early initiation of
             CR continued throughout a life span did not negatively
             impact bone structural properties.},
   Doi = {10.1007/s11357-014-9669-5},
   Key = {fds241059}
}

@article{fds241060,
   Author = {Sparling, TL and Schmitt, D and Miller, CE and Guilak, F and Somers, TJ and Keefe, FJ and Queen, RM},
   Title = {Energy recovery in individuals with knee
             osteoarthritis},
   Journal = {Osteoarthritis and Cartilage},
   Volume = {22},
   Number = {6},
   Pages = {747-755},
   Year = {2014},
   Month = {January},
   ISSN = {1063-4584},
   url = {http://dx.doi.org/10.1016/j.joca.2014.04.004},
   Abstract = {Objective: Pathological gaits have been shown to limit
             transfer between potential (PE) and kinetic (KE) energy
             during walking, which can increase locomotor costs. The
             purpose of this study was to examine whether energy exchange
             would be limited in people with knee osteoarthritis (OA).
             Methods: Ground reaction forces during walking were
             collected from 93 subjects with symptomatic knee OA
             (self-selected and fast speeds) and 13 healthy controls
             (self-selected speed) and used to calculate their center of
             mass (COM) movements, PE and KE relationships, and energy
             recovery during a stride. Correlations and linear
             regressions examined the impact of energy fluctuation phase
             and amplitude, walking velocity, body mass, self-reported
             pain, and radiographic severity on recovery. Paired t-tests
             were run to compare energy recovery between cohorts.
             Results: Symptomatic knee OA subjects displayed lower
             energetic recovery during self-selected walking speeds than
             healthy controls (P=0.0018). PE and KE phase relationships
             explained the majority (66%) of variance in recovery.
             Recovery had a complex relationship with velocity and its
             change across speeds was significantly influenced by the
             self-selected walking speed of each subject. Neither
             radiographic OA scores nor subject self-reported measures
             demonstrated any relationship with energy recovery.
             Conclusions: Knee OA reduces effective exchange of PE and
             KE, potentially increasing the muscular work required to
             control movements of the COM. Gait retraining may return
             subjects to more normal patterns of energy exchange and
             allow them to reduce fatigue. © 2014 Osteoarthritis
             Research Society International.},
   Doi = {10.1016/j.joca.2014.04.004},
   Key = {fds241060}
}

@article{fds241066,
   Author = {Granatosky, MC and Lemelin, P and Chester, SGB and Pampush, JD and Schmitt, D},
   Title = {Functional and evolutionary aspects of axial stability in
             euarchontans and other mammals},
   Journal = {Journal of Morphology},
   Volume = {275},
   Number = {3},
   Pages = {313-327},
   Year = {2013},
   ISSN = {0362-2525},
   url = {http://dx.doi.org/10.1002/jmor.20216},
   Keywords = {arboreal • back • locomotion • primates
             • ribs • vertebra},
   Abstract = {The presence of a stable thoracolumbar region, found in many
             arboreal mammals, is considered advantageous for bridging
             and cantilevering between discontinuous branches. However,
             no study has directly explored the link between osteological
             features cited as enhancing axial stability and the
             frequency of cantilevering and bridging behaviors in a
             terminal branch environment. To fill this gap, we collected
             metric data on costal and vertebral morphology of primate
             and nonprimate mammals known to cantilever and bridge
             frequently and those that do not. We also quantified the
             frequency and duration of cantilevering and bridging
             behaviors using experimental setups for species that have
             been reported to show differences in use of small branches
             and back anatomy (Caluromys philander, Loris tardigradus,
             Monodelphis domestica, and Cheirogaleus medius).
             Phylogenetically corrected principal component analysis
             reveals that taxa employing frequent bridging and
             cantilevering (C. philander and lorises) also exhibit
             reduced intervertebral and intercostal spaces, which can
             serve to increase thoracolumbar stability, when compared to
             closely related species (M. domestica and C. medius). We
             observed C. philander cantilevering and bridging
             significantly more often than M. domestica, which never
             cantilevered or crossed any arboreal gaps. Although no
             difference in the frequency of cantilevering was observed
             between L. tardigradus and C. medius, the duration of
             cantilevering bouts was significantly greater in L.
             tardigradus. These data suggest that osteological features
             promoting axial rigidity may be part of a morpho-behavioral
             complex that increases stability in mammals moving and
             foraging in a terminal branch environment. © 2013 Wiley
             Periodicals, Inc.},
   Language = {ENG},
   Doi = {10.1002/jmor.20216},
   Key = {fds241066}
}

@article{fds241068,
   Author = {Griffin, NL and Miller, C and Schmitt, D and D'Août,
             K},
   Title = {An investigation of the dynamic relationship between
             navicular drop and first metatarsophalangeal joint dorsal
             excursion},
   Journal = {Journal of Anatomy},
   Volume = {222},
   Number = {6},
   Pages = {598-607},
   Year = {2013},
   ISSN = {0021-8782},
   url = {http://dx.doi.org/10.1111/joa.12050},
   Keywords = {Adult • Aged • Female • Foot • Gait
             • Humans • India • Male •
             Metatarsophalangeal Joint • Middle Aged •
             Pronation • Regression Analysis • Tarsal Bones
             • Walking • Young Adult • anatomy & histology
             • physiology • physiology*},
   Abstract = {The modern human foot is a complex biomechanical structure
             that must act both as a shock absorber and as a propulsive
             strut during the stance phase of gait. Understanding the
             ways in which foot segments interact can illuminate the
             mechanics of foot function in healthy and pathological
             humans. It has been proposed that increased values of medial
             longitudinal arch deformation can limit metatarsophalangeal
             joint excursion via tension in the plantar aponeurosis.
             However, this model has not been tested directly in a
             dynamic setting. In this study, we tested the hypothesis
             that during the stance phase, subtalar pronation (stretching
             of the plantar aponeurosis and subsequent lowering of the
             medial longitudinal arch) will negatively affect the amount
             of first metatarsophalangeal joint excursion occurring at
             push-off. Vertical descent of the navicular (a proxy for
             subtalar pronation) and first metatarsophalangeal joint
             dorsal excursion were measured during steady locomotion over
             a flat substrate on a novel sample consisting of
             asymptomatic adult males and females, many of whom are
             habitually unshod. Least-squares regression analyses
             indicated that, contrary to the hypothesis, navicular drop
             did not explain a significant amount of variation in first
             metatarsophalangeal joint dorsal excursion. These results
             suggest that, in an asymptomatic subject, the plantar
             aponeurosis and the associated foot bones can function
             effectively within the normal range of subtalar pronation
             that takes place during walking gait. From a clinical
             standpoint, this study highlights the need for investigating
             the in vivo kinematic relationship between subtalar
             pronation and metatarsophalangeal joint dorsiflexion in
             symptomatic populations, and also the need to explore other
             factors that may affect the kinematics of asymptomatic feet.
             © 2013 Anatomical Society.},
   Language = {eng},
   Doi = {10.1111/joa.12050},
   Key = {fds241068}
}

@article{fds241062,
   Author = {O'Neill, MC and Schmitt, D},
   Title = {Erratum: The gaits of primates: Center of mass mechanics in
             walking, cantering and galloping ring-tailed lemurs, Lemur
             catta ((1994) Journal of Experimental Biology 215
             (1728-1739))},
   Journal = {The Journal of Experimental Biology},
   Volume = {215},
   Number = {11},
   Pages = {1994},
   Publisher = {The Company of Biologists},
   Year = {2012},
   Month = {June},
   ISSN = {0022-0949},
   url = {http://dx.doi.org/10.1242/jeb.074500},
   Doi = {10.1242/jeb.074500},
   Key = {fds241062}
}

@article{fds241085,
   Author = {Somers, TJ and Blumenthal, JA and Guilak, F and Kraus, VB and Schmitt,
             DO and Babyak, MA and Craighead, LW and Caldwell, DS and Rice, JR and McKee, DC and Shelby, RA and Campbell, LC and Pells, JJ and Sims, EL and Queen, R and Carson, JW and Connelly, M and Dixon, KE and Lacaille, LJ and Huebner, JL and Rejeski, WJ and Keefe, FJ},
   Title = {Pain coping skills training and lifestyle behavioral weight
             management in patients with knee osteoarthritis: a
             randomized controlled study.},
   Journal = {Pain},
   Volume = {153},
   Number = {6},
   Pages = {1199-1209},
   Year = {2012},
   Month = {June},
   ISSN = {1872-6623},
   url = {http://www.ncbi.nlm.nih.gov/pubmed/22503223},
   Abstract = {Overweight and obese patients with osteoarthritis (OA)
             experience more OA pain and disability than patients who are
             not overweight. This study examined the long-term efficacy
             of a combined pain coping skills training (PCST) and
             lifestyle behavioral weight management (BWM) intervention in
             overweight and obese OA patients. Patients (n=232) were
             randomized to a 6-month program of: 1) PCST+BWM; 2)
             PCST-only; 3) BWM-only; or 4) standard care control.
             Assessments of pain, physical disability (Arthritis Impact
             Measurement Scales [AIMS] physical disability, stiffness,
             activity, and gait), psychological disability (AIMS
             psychological disability, pain catastrophizing, arthritis
             self-efficacy, weight self-efficacy), and body weight were
             collected at 4 time points (pretreatment, posttreatment, and
             6 months and 12 months after the completion of treatment).
             Patients randomized to PCST+BWM demonstrated significantly
             better treatment outcomes (average of all 3 posttreatment
             values) in terms of pain, physical disability, stiffness,
             activity, weight self-efficacy, and weight when compared to
             the other 3 conditions (Ps<0.05). PCST+BWM also did
             significantly better than at least one of the other
             conditions (ie, PCST-only, BWM-only, or standard care) in
             terms of psychological disability, pain catastrophizing, and
             arthritis self-efficacy. Interventions teaching overweight
             and obese OA patients pain coping skills and weight
             management simultaneously may provide the more comprehensive
             long-term benefits.},
   Language = {eng},
   Doi = {10.1016/j.pain.2012.02.023},
   Key = {fds241085}
}

@article{fds241081,
   Author = {O'Neill, MC and Schmitt, D},
   Title = {The gaits of primates: center of mass mechanics in walking,
             cantering and galloping ring-tailed lemurs, Lemur
             catta.},
   Journal = {The Journal of Experimental Biology},
   Volume = {215},
   Number = {Pt 10},
   Pages = {1728-1739},
   Year = {2012},
   Month = {May},
   ISSN = {0022-0949},
   url = {http://dx.doi.org/10.1242/jeb.052340},
   Keywords = {Algorithms • Animals • Behavior, Animal •
             Biomechanics • Female • Gait • Gravitation
             • Kinetics • Lemur • Male • Models,
             Statistical • Movement • Primates • Running*
             • Walking* • physiology*},
   Abstract = {Most primates, including lemurs, have a broad range of
             locomotor capabilities, yet much of the time, they walk at
             slow speeds and amble, canter or gallop at intermediate and
             fast speeds. Although numerous studies have investigated
             limb function during primate quadrupedalism, how the center
             of mass (COM) moves is not well understood. Here, we
             examined COM energy, work and power during walking,
             cantering and galloping in ring-tailed lemurs, Lemur catta
             (N=5), over a broad speed range (0.43-2.91 m s(-1)). COM
             energy recoveries were substantial during walking (35-71%)
             but lower during canters and gallops (10-51%). COM work,
             power and collisional losses increased with speed. The
             positive COM works were 0.625 J kg(-1) m(-1) for walks and
             1.661 J kg(-1) m(-1) for canters and gallops, which are in
             the middle range of published values for terrestrial
             animals. Although some discontinuities in COM mechanics were
             evident between walking and cantering, there was no apparent
             analog to the trot-gallop transition across the intermediate
             and fast speed range (dimensionless v>0.75, Fr>0.5). A
             phenomenological model of a lemur cantering and trotting at
             the same speed shows that canters ensure continuous contact
             of the body with the substrate while reducing peak vertical
             COM forces, COM stiffness and COM collisions. We suggest
             that cantering, rather than trotting, at intermediate speeds
             may be tied to the arboreal origins of the Order Primates.
             These data allow us to better understand the mechanics of
             primate gaits and shed new light on primate locomotor
             evolution.},
   Language = {eng},
   Doi = {10.1242/jeb.052340},
   Key = {fds241081}
}

@article{fds241086,
   Author = {Allen, KD and Mata, BA and Gabr, MA and Huebner, JL and Adams, SB and Kraus, VB and Schmitt, DO and Setton, LA},
   Title = {Kinematic and dynamic gait compensations resulting from knee
             instability in a rat model of osteoarthritis.},
   Journal = {Arthritis Research & Therapy},
   Volume = {14},
   Number = {2},
   Pages = {R78},
   Year = {2012},
   Month = {April},
   ISSN = {1478-6362},
   url = {http://www.ncbi.nlm.nih.gov/pubmed/22510443},
   Abstract = {Osteoarthritis (OA) results in pain and disability; however,
             preclinical OA models often focus on joint-level changes.
             Gait analysis is one method used to evaluate both
             preclinical OA models and OA patients. The objective of this
             study is to describe spatiotemporal and ground reaction
             force changes in a rat medial meniscus transection (MMT)
             model of knee OA and to compare these gait measures with
             assays of weight bearing and tactile allodynia.Sixteen rats
             were used in the study. The medial collateral ligament (MCL)
             was transected in twelve Lewis rats (male, 200 to 250 g); in
             six rats, the medial meniscus was transected, and the
             remaining six rats served as sham controls. The remaining
             four rats served as naïve controls. Gait, weight-bearing as
             measured by an incapacitance meter, and tactile allodynia
             were assessed on postoperative days 9 to 24. On day 28, knee
             joints were collected for histology. Cytokine concentrations
             in the serum were assessed with a 10-plex cytokine
             panel.Weight bearing was not affected by sham or MMT
             surgery; however, the MMT group had decreased mechanical
             paw-withdrawal thresholds in the operated limb relative to
             the contralateral limb (P = 0.017). The gait of the MMT
             group became increasingly asymmetric from postoperative days
             9 to 24 (P = 0.020); moreover, MMT animals tended to spend
             more time on their contralateral limb than their operated
             limb while walking (P < 0.1). Ground reaction forces
             confirmed temporal shifts in symmetry and stance time, as
             the MMT group had lower vertical and propulsive ground
             reaction forces in their operated limb relative to the
             contralateral limb, naïve, and sham controls (P < 0.05).
             Levels of interleukin 6 in the MMT group tended to be higher
             than naïve controls (P = 0.072). Histology confirmed
             increased cartilage damage in the MMT group, consistent with
             OA initiation. Post hoc analysis revealed that gait
             symmetry, stance time imbalance, peak propulsive force, and
             serum interleukin 6 concentrations had significant
             correlations to the severity of cartilage lesion
             formation.These data indicate significant gait compensations
             were present in the MMT group relative to medial collateral
             ligament (MCL) injury (sham) alone and naïve controls.
             Moreover, these data suggest that gait compensations are
             likely driven by meniscal instability and/or cartilage
             damage, and not by MCL injury alone.},
   Language = {eng},
   Doi = {10.1186/ar3801},
   Key = {fds241086}
}

@article{fds241079,
   Author = {Workman, C and Schmitt, D},
   Title = {Erratum to: Positional Behavior of Delacour's Langurs
             (Trachypithecus delacouri) in Northern Vietnam (Int J
             Primatol, 10.1007/s10764-011-9547-2)},
   Journal = {International Journal of Primatology},
   Volume = {33},
   Number = {1},
   Pages = {38-39},
   Publisher = {Springer Nature},
   Year = {2012},
   Month = {February},
   ISSN = {0164-0291},
   url = {http://dx.doi.org/10.1007/s10764-012-9577-4},
   Doi = {10.1007/s10764-012-9577-4},
   Key = {fds241079}
}

@article{fds241080,
   Author = {Workman, C and Schmitt, D},
   Title = {Positional Behavior of Delacour's Langurs (Trachypithecus
             delacouri) in Northern Vietnam},
   Journal = {International Journal of Primatology},
   Volume = {33},
   Number = {1},
   Pages = {19-37},
   Publisher = {Springer Nature},
   Year = {2012},
   Month = {February},
   ISSN = {0164-0291},
   url = {http://dx.doi.org/10.1007/s10764-011-9547-2},
   Abstract = {Information on positional behavior can help elucidate
             relationships between a species' morphology, behavior, and
             environment. Delacour's langurs (Trachypithecus delacouri)
             are similar to other colobines in body mass and intermembral
             index, yet inhabit a limestone karst environment. From
             August 2007 to July 2008, we collected 372 h of positional
             behavior and substrate use data from 8 groups of
             Trachypithecus delacouri in Van Long Nature Reserve, Vietnam
             to address questions about how the distinct -and potentially
             dangerous- features of karst influence colobine positional
             behavior. Results show that Trachypithecus delacouri is
             predominantly quadrupedal (66%). However, they exhibit
             differences that set them apart from many other colobines.
             Nearly 80% of locomotor and postural behaviors were
             performed on rocks. Leaping was remarkably infrequent,
             representing only 6% of overall locomotion. They leapt 3
             times more frequently on trees (13%) than on rocks (4%) and
             more frequently used trees as a landing substrate than rocks
             (38% vs. 23%), both significant differences. We argue that
             rock (and cliff) travel is altogether different from
             terrestrial and arboreal travel and propose using the term
             petrous to indicate the substrate and incorporate the
             implications of its precise sharpness and verticality that
             lead to the complexities and risk of locomotion on rock
             surfaces. Trachypithecus delacouri does not show specific
             adaptations for limestone karst. Instead they appear to be a
             behaviorally flexible species and, owing to the generalized
             locomotor capabilities that characterize cercopithecids,
             capable of locomoting through and living in the limestone
             rock environment to which they have relatively recently been
             restricted. © 2011 Springer Science+Business Media,
             LLC.},
   Doi = {10.1007/s10764-011-9547-2},
   Key = {fds241080}
}

@article{fds241093,
   Author = {Allen, KD and Shamji, MF and Mata, BA and Gabr, MA and Sinclair, SM and Schmitt, DO and Richardson, WJ and Setton, LA},
   Title = {Kinematic and dynamic gait compensations in a rat model of
             lumbar radiculopathy and the effects of tumor necrosis
             factor-alpha antagonism.},
   Journal = {Arthritis Research & Therapy},
   Volume = {13},
   Number = {4},
   Pages = {R137},
   Year = {2011},
   Month = {August},
   ISSN = {1478-6362},
   url = {http://www.ncbi.nlm.nih.gov/pubmed/21871102},
   Abstract = {INTRODUCTION: Tumor necrosis factor-α (TNFα) has received
             significant attention as a mediator of lumbar radiculopathy,
             with interest in TNF antagonism to treat radiculopathy.
             Prior studies have demonstrated that TNF antagonists can
             attenuate heightened nociception resulting from lumbar
             radiculopathy in the preclinical model. Less is known about
             the potential impact of TNF antagonism on gait
             compensations, despite being of clinical relevance. In this
             study, we expand on previous descriptions of gait
             compensations resulting from lumbar radiculopathy in the rat
             and describe the ability of local TNF antagonism to prevent
             the development of gait compensations, altered weight
             bearing, and heightened nociception. METHODS: Eighteen male
             Sprague-Dawley rats were investigated for mechanical
             sensitivity, weight-bearing, and gait pre- and
             post-operatively. For surgery, tail nucleus pulposus (NP)
             tissue was collected and the right L5 dorsal root ganglion
             (DRG) was exposed (Day 0). In sham animals, NP tissue was
             discarded (n = 6); for experimental animals, autologous NP
             was placed on the DRG with or without 20 μg of soluble TNF
             receptor type II (sTNFRII, n = 6 per group). Spatiotemporal
             gait characteristics (open arena) and mechanical sensitivity
             (von Frey filaments) were assessed on post-operative Day 5;
             gait dynamics (force plate arena) and weight-bearing
             (incapacitance meter) were assessed on post-operative Day 6.
             RESULTS: High-speed gait characterization revealed animals
             with NP alone had a 5% decrease in stance time on their
             affected limbs on Day 5 (P ≤0.032). Ground reaction force
             analysis on Day 6 aligned with temporal changes observed on
             Day 5, with vertical impulse reduced in the affected limb of
             animals with NP alone (area under the vertical force-time
             curve, P <0.02). Concordant with gait, animals with NP alone
             also had some evidence of affected limb mechanical allodynia
             on Day 5 (P = 0.08) and reduced weight-bearing on the
             affected limb on Day 6 (P <0.05). Delivery of sTNFRII at the
             time of NP placement ameliorated signs of mechanical
             hypersensitivity, imbalanced weight distribution, and gait
             compensations (P <0.1). CONCLUSIONS: Our data indicate gait
             characterization has value for describing early limb
             dysfunctions in pre-clinical models of lumbar radiculopathy.
             Furthermore, TNF antagonism prevented the development of
             gait compensations subsequent to lumbar radiculopathy in our
             model.},
   Language = {eng},
   Doi = {10.1186/ar3451},
   Key = {fds241093}
}

@article{ref1,
   Author = {Hanna, JB and Schmitt, D},
   Title = {Comparative Triceps Surae Morphology in Primates: A
             Review},
   Journal = {Anatomy Research International},
   Volume = {2011},
   Pages = {1-22},
   Publisher = {Hindawi Limited},
   Year = {2011},
   Month = {July},
   url = {http://dx.doi.org/10.1155/2011/191509},
   Abstract = {<jats:p>Primate locomotor evolution, particularly the
             evolution of bipedalism, is often examined through
             morphological studies. Many of these studies have examined
             the uniqueness of the primate forelimb, and others have
             examined the primate hip and thigh. Few data exist, however,
             regarding the myology and function of the leg muscles, even
             though the ankle plantar flexors are highly important during
             human bipedalism. In this paper, we draw together data on
             the fiber type and muscle mass variation in the ankle
             plantar flexors of primates and make comparisons to other
             mammals. The data suggest that great apes, atelines, and
             lorisines exhibit similarity in the mass distribution of the
             triceps surae. We conclude that variation in triceps surae
             may be related to the shared locomotor mode exhibited by
             these groups and that triceps surae morphology, which
             approaches that of humans, may be related to frequent use of
             semiplantigrade locomotion and vertical climbing.</jats:p>},
   Doi = {10.1155/2011/191509},
   Key = {ref1}
}

@article{springerlink:10.1007/s10764-010-9479-2,
   Author = {Hanna, JB and Schmitt, D},
   Title = {Interpreting the Role of Climbing in Primate Locomotor
             Evolution: Are the Biomechanics of Climbing Influenced by
             Habitual Substrate Use and Anatomy?},
   Journal = {International Journal of Primatology},
   Volume = {32},
   Number = {2},
   Pages = {430-444},
   Publisher = {Springer Nature},
   Organization = {Department of Biomedical Sciences, West Virginia School of
             Osteopathic Medicine, Lewisburg, WV 24901,
             USA},
   Institution = {Department of Biomedical Sciences, West Virginia School of
             Osteopathic Medicine, Lewisburg, WV 24901,
             USA},
   Year = {2011},
   Month = {April},
   ISSN = {0164-0291},
   url = {http://dx.doi.org/10.1007/s10764-010-9479-2},
   Abstract = {Vertical climbing is widely accepted to have played an
             important role in the origins of both primate locomotion and
             of human bipedalism. Yet, only a few researchers have
             compared climbing mechanics in quadrupedal primates that
             vary in their degree of arboreality. It is assumed that
             primates using vertical climbing with a relatively high
             frequency will have morphological and behavioral
             specializations that facilitate efficient climbing
             mechanics. We test this assumption by examining whether time
             spent habitually engaged in climbing influences locomotor
             parameters such as footfall sequence, peak forces, and joint
             excursions during vertical climbing. Previous studies have
             shown that during climbing, the pronograde and
             semiterrestrial Macaca fuscata differs in these parameters
             compared to the more arboreal and highly specialized,
             antipronograde Ateles geoffroyi. Here, we examine whether a
             fully arboreal, quadrupedal primate that does not regularly
             arm-swing will exhibit gait and force distribution patterns
             intermediate between those of Macaca fuscata and Ateles
             geoffroyi. We collected footfall sequence, limb peak
             vertical forces, and 3D hindlimb excursion data for Macaca
             fascicularis during climbing on a stationary pole
             instrumented with a force transducer. Results show that
             footfall sequences are similar between macaque species,
             whereas peak force distributions and hindlimb excursions for
             Macaca fascicularis are intermediate between values reported
             for M. fuscata and Ateles geoffroyi. These results support
             the notion that time spent climbing is reflected in climbing
             mechanics, even though morphology may not provide for
             efficient mechanics, and highlight the important role of
             arboreal locomotor activity in determining the pathways of
             primate locomotor evolution. © 2010 Springer
             Science+Business Media, LLC.},
   Doi = {10.1007/s10764-010-9479-2},
   Key = {springerlink:10.1007/s10764-010-9479-2}
}

@article{fds241089,
   Author = {Hanna, JB and Schmitt, D},
   Title = {Locomotor energetics in primates: Gait mechanics and their
             relationship to the energetics of vertical and horizontal
             locomotion},
   Journal = {American Journal of Physical Anthropology},
   Volume = {145},
   Number = {1},
   Pages = {43-54},
   Year = {2011},
   ISSN = {0002-9483},
   url = {http://dx.doi.org/10.1002/ajpa.21465},
   Keywords = {Air • Animals • Body Weight • Energy
             Metabolism • Gait • Locomotion • Oxygen
             • Oxygen Consumption • Saimiri • Strepsirhini
             • Video Recording • analysis • metabolism
             • physiology*},
   Abstract = {All primates regularly move within three-dimensional
             arboreal environments and must often climb, but little is
             known about the energetic costs of this critical activity.
             Limited previous work on the energetics of incline
             locomotion suggests that there may be differential selective
             pressures for large compared to small primates in choosing
             to exploit a complex arboreal environment. Necessary
             metabolic and gait data have never been collected to examine
             this possibility and biomechanical mechanisms that might
             explain size-based differences in the cost of arboreal
             movement. Energetics and kinematics were collected for five
             species of primate during climbing and horizontal
             locomotion. Subjects moved on a treadmill with a narrow
             vertical substrate and one with a narrow horizontal
             substrate at their maximum sustainable speed for 10-20 min
             while oxygen consumption was monitored. Data during climbing
             were compared to those during horizontal locomotion and
             across size. Results show that climbing energetic costs were
             similar to horizontal costs for small primates (&lt;0.5 kg)
             but were nearly double for larger species. Spatio-temporal
             gait characteristics suggest that the relationship between
             the cost of locomotion and the rate of force production
             changes between the two locomotor modes. Thus, the main
             determinants of climbing costs are fundamentally different
             from those during horizontal locomotion. These new results
             combining spatiotemporal and energetic data confirm and
             expand on our previous argument (Hanna et al.: Science 320
             (2008) 898) that similar costs of horizontal and vertical
             locomotion in small primates facilitated the successful
             occupation of a fine-branch arboreal milieu by the earliest
             primates. © 2011 Wiley-Liss, Inc.},
   Language = {eng},
   Doi = {10.1002/ajpa.21465},
   Key = {fds241089}
}

@article{fds241050,
   Author = {Schmitt, D},
   Title = {Primate Locomotor Evolution: Biomechanical Studies of
             Primate Locomotion and Their Implications for Understanding
             Primate Neuroethology},
   Pages = {31-63},
   Publisher = {Oxford University Press},
   Year = {2010},
   Month = {February},
   url = {http://dx.doi.org/10.1093/acprof:oso/9780195326598.003.0003},
   Abstract = {© 2010 by Michael L. Platt and Asif A. Ghazanfar. All
             rights reserved. This chapter argues that primates
             (including humans) show patterns of locomotion and locomotor
             control that are different from all other mammals. Changes
             in limb function associated with the adaptive
             diversification of locomotor patterns in the primate clade
             probably required the evolution of profound specializations
             in the neural control of locomotion. Most of these putative
             specializations remain unknown or unexplored. This
             realization suggests that comparative studies of the
             neuroethology of locomotion in primates may offer unique
             insights into motor control, and such insights may have
             implications for fields as diverse as robotics and the
             clinical treatment of paralysis with brain-machine interface
             devices.},
   Doi = {10.1093/acprof:oso/9780195326598.003.0003},
   Key = {fds241050}
}

@article{fds241092,
   Author = {Schmitt, D and Gruss, LT and Lemelin, P},
   Title = {Brief communication: Forelimb compliance in arboreal and
             terrestrial opossums},
   Journal = {American Journal of Physical Anthropology},
   Volume = {141},
   Number = {1},
   Pages = {142-146},
   Year = {2010},
   ISSN = {0002-9483},
   url = {http://dx.doi.org/10.1002/ajpa.21145},
   Keywords = {Animals • Behavior, Animal • Biological Evolution
             • Biomechanics • Forelimb • Locomotion •
             Opossums • anatomy & histology* •
             physiology},
   Abstract = {Primates display high forelimb compliance (increased elbow
             joint yield) compared to most other mammals. Forelimb
             compliance, which is especially marked among arboreal
             primates, moderates vertical oscillations of the body and
             peak vertical forces and may represent a basal adaptation of
             primates for locomotion on thin, flexible branches. However,
             Larney and Larson (Am J Phys Anthropol 125 [2004] 42-50)
             reported that marsupials have forelimb compliance comparable
             to or greater than that of most primates, but did not
             distinguish between arboreal and terrestrial marsupials. If
             forelimb compliance is functionally linked to locomotion on
             thin branches, then elbow yield should be highest in
             marsupials relying on arboreal substrates more often. To
             test this hypothesis, we compared forelimb compliance
             between two didelphid marsupials, Caluromys philander (an
             arboreal opossum relying heavily on thin branches) and
             Monodelphis domestica (an opossum that spends most of its
             time on the ground). Animals were videorecorded while
             walking on a runway or a horizontal 7-mm pole. Caluromys
             showed higher elbow yield (greater changes in degrees of
             elbow flexion) on both substrates, similar to that reported
             for arboreal primates. Monodelphis was characterized by
             lower elbow yield that was intermediate between the values
             reported by Larney and Larson (Am J Phys Anthropol 125
             [2004] 42-50) for more terrestrial primates and rodents.
             This finding adds evidence to a model suggesting a
             functional link between arboreality-particularly locomotion
             on thin, flexible branches-and forelimb compliance. These
             data add another convergent trait between arboreal primates,
             Caluromys, and other arboreal marsupials and support the
             argument that all primates evolved from a common ancestor
             that was a fine-branch arborealist. © 2009 Wiley-Liss,
             Inc.},
   Language = {eng},
   Doi = {10.1002/ajpa.21145},
   Key = {fds241092}
}

@article{fds241094,
   Author = {Schmitt, D and Zumwalt, AC and Hamrick, MW},
   Title = {The relationship between bone mechanical properties and
             ground reaction forces in normal and hypermuscular
             mice},
   Journal = {Journal of Experimental Zoology. Part A, Ecological Genetics
             and Physiology},
   Volume = {313 A},
   Number = {6},
   Pages = {339-351},
   Year = {2010},
   ISSN = {1932-5223},
   url = {http://dx.doi.org/10.1002/jez.604},
   Keywords = {Animals • Biomechanics • Bone and Bones •
             Mice • Muscle, Skeletal • Organ Size •
             physiology*},
   Abstract = {Understanding the relationship between external load and
             bone morphology is critical for understanding adaptations to
             load in extant animals and inferring behavior in extinct
             forms. Yet, the relationship between bony anatomy and load
             is poorly understood, with empirical studies often producing
             conflicting results. It is widely assumed in many ecological
             and paleontological studies that bone size and strength
             reflect the forces experienced by the bone in vivo. This
             study examines that assumption by providing preliminary data
             on gait mechanics in a hypermuscular myostatin-deficient
             mouse model with highly mineralized and hypertrophied long
             bones. A small sample of hypermuscular and wild-type mice
             was video recorded while walking freely across a force
             platform. Temporal gait parameters, peak vertical and
             transverse (mediolateral) ground reaction forces (GRFs),
             vertical impulse, and loading rates were measured. The only
             gait parameters that differed between the two groups were
             the speeds at which the animals traveled and the transverse
             forces on the hind limb. The myostatin-deficient mice move
             relatively slowly and experienced the same magnitude of
             vertical forces on all limbs and transverse forces on the
             forelimb as the wild-type mice; though the
             myostatin-deficient mice did experience lower mediolateral
             forces on their hindlimbs compared with the wild-type mice.
             These preliminary results call into question the hypothesis
             that skeletal hypertrophy observed in hypermuscular mice is
             a result of larger GRFs experienced by the animals' limbs
             during locomotion. This calls for further analysis and a
             cautious approach to inferences about locomotor behavior
             derived from bony morphology in extant and fossil species.
             © 2010 Wiley-Liss, Inc.},
   Language = {eng},
   Doi = {10.1002/jez.604},
   Key = {fds241094}
}

@article{fds241096,
   Author = {Kivell, TL and Schmitt, D and Wunderlich, RE},
   Title = {Hand and foot pressures in the aye-aye (Daubentonia
             madagascariensis) reveal novel biomechanical trade-offs
             required for walking on gracile digits},
   Journal = {The Journal of Experimental Biology},
   Volume = {213},
   Number = {9},
   Pages = {1549-1557},
   Year = {2010},
   ISSN = {0022-0949},
   url = {http://hdl.handle.net/10161/4193 Duke open
             access},
   Keywords = {Animals • Biomechanics • Foot • Hand •
             Posture • Strepsirhini • Walking* •
             physiology • physiology*},
   Abstract = {Arboreal animals with prehensile hands must balance the
             complex demands of bone strength, grasping and manipulation.
             An informative example of this problem is that of the
             aye-aye (Daubentonia madagascariensis), a rare lemuriform
             primate that is unusual in having exceptionally long,
             gracile fingers specialized for foraging. In addition, they
             are among the largest primates to engage in head-first
             descent on arboreal supports, a posture that should increase
             loads on their gracile digits. We test the hypothesis that
             aye-ayes will reduce pressure on their digits during
             locomotion by curling their fingers off the substrate. This
             hypothesis was tested using simultaneous Videographic and
             pressure analysis of the hand, foot and digits for five
             adult aye-ayes during horizontal locomotion and during
             ascent and descent on a 30° instrumented runway. Aye-ayes
             consistently curled their fingers during locomotion on all
             slopes. When the digits were in contact with the substrate,
             pressures were negligible and significantly less than those
             experienced by the palm or pedal digits. In addition,
             aye-ayes lifted their hands vertically off the substrate
             instead of 'toeing-off' and descended head-first at
             significantly slower speeds than on other slopes. Pressure
             on the hand increased during head-first descent relative to
             horizontal locomotion but not as much as the pressure
             increased on the foot during ascent. This distribution of
             pressure suggests that aye-ayes shift their weight
             posteriorly during head-first descent to reduce loads on
             their gracile fingers. This research demonstrates several
             novel biomechanical trade-offs to deal with complex
             functional demands on the mammalian skeleton. © 2010.
             Published by The Company ot Biologists Ltd.},
   Language = {eng},
   Doi = {10.1242/jeb.040014},
   Key = {fds241096}
}

@article{fds241095,
   Author = {Sims, EL and Keefe, FJ and Kraus, VB and Guilak, F and Queen, RM and Schmitt, D},
   Title = {Racial differences in gait mechanics associated with knee
             osteoarthritis.},
   Journal = {Aging Clinical and Experimental Research},
   Volume = {21},
   Number = {6},
   Pages = {463-469},
   Year = {2009},
   Month = {December},
   ISSN = {1594-0667},
   url = {http://www.ncbi.nlm.nih.gov/pubmed/20154517},
   Keywords = {Adult • African Continental Ancestry Group* • Aged
             • Anthropometry • Disability Evaluation •
             Educational Status • European Continental Ancestry
             Group* • Female • Gait • Humans • Knee
             Joint • Male • Middle Aged • Osteoarthritis,
             Knee • Range of Motion, Articular • Self Concept
             • Severity of Illness Index • ethnology* •
             physiology • physiology* • physiopathology •
             physiopathology*},
   Abstract = {BACKGROUND AND AIMS: This study examines racial differences
             in gait mechanics in persons with knee osteoarthritis and
             the influence of anthropometrics, educational level,
             radiographic disease severity (rOA), and self-report
             measures of pain and disability on racial differences in
             gait. METHODS: One hundred seventy five (64 black and 111
             white) adults with radiographic knee OA were tested. 3-D
             kinematic and kinetic data were collected while subjects
             walked at two self-selected speeds (normal and fast).
             Anthropometric data, radiographic level of OA, and
             self-report measures of pain and disability were also
             collected. Gait patterns were compared across groups and
             within groups. RESULTS: Black and white subjects did not
             differ significantly in radiographic OA. However, blacks
             walked significantly more slowly when asked to walk fast. At
             the normal speed, blacks had a smaller knee range of motion
             and loading rate than whites. Blacks also took longer to
             reach their peak maximum ground reaction force than whites.
             Within black subjects variations in gait mechanics were
             primarily explained by BMI, rOA, selfreported psychological
             disability, and pain self-efficacy. In white subjects,
             variations in gait mechanics were primarily explained by
             weight, age, velocity, psychological disability, and
             self-efficacy. CONCLUSIONS: Blacks in this study had a
             pattern of gait mechanics generally associated with high
             levels of osteoarthritis, though they did not differ
             significantly in rOA from whites. The variability in gait
             patterns exhibited by blacks was most strongly related to
             variance in walking speed, anthropometrics, and perceived
             physical ability. Taken together, these results suggest that
             race is an important factor that must be considered in the
             treatment and study of osteoarthritis.},
   Language = {eng},
   Doi = {10.1007/bf03327442},
   Key = {fds241095}
}

@article{fds241091,
   Author = {Nebel, MB and Sims, EL and Keefe, FJ and Kraus, VB and Guilak, F and Caldwell, DS and Pells, JJ and Queen, R and Schmitt,
             D},
   Title = {The relationship of self-reported pain and functional
             impairment to gait mechanics in overweight and obese persons
             with knee osteoarthritis.},
   Journal = {Arch Phys Med Rehabil},
   Volume = {90},
   Number = {11},
   Pages = {1874-1879},
   Year = {2009},
   Month = {November},
   ISSN = {1532-821X},
   url = {http://www.ncbi.nlm.nih.gov/pubmed/19887211},
   Keywords = {Disability Evaluation* • Disabled Persons • Female
             • Gait • Humans • Male • Middle Aged
             • Obesity • Osteoarthritis, Knee •
             Overweight* • Pain • Pain Measurement •
             Regression Analysis • Self Disclosure •
             complications • etiology* • physiology* •
             physiopathology*},
   Abstract = {OBJECTIVE: To examine the degree to which 2 commonly used
             measures of pain and disability, the Arthritis Impact
             Measurement Scales (AIMS) and the Western Ontario and
             McMaster Universities Osteoarthritis Index (WOMAC), relate
             to objective gait measurements. DESIGN: A descriptive study
             of the influence of self-reported pain and perceived
             functional impairment on gait mechanics in osteoarthritic
             adults. SETTING: A university clinical research laboratory.
             PARTICIPANTS: Overweight/obese adults with radiographic knee
             osteoarthritis (OA) as well as pain and disability
             associated with the disease (N=179). INTERVENTIONS: Not
             applicable. MAIN OUTCOME MEASURES: The AIMS and WOMAC were
             administered to determine self-report measures of pain and
             disability. Speed, stride length, support time, knee angle,
             and peak vertical force (PVF) were determined from
             3-dimensional kinematic and kinetic data collected on
             subjects walking at self-selected normal and fast speeds.
             Anthropometric data and radiographic levels of OA were also
             collected. RESULTS: Pearson correlation analysis showed that
             the AIMS physical disability score was inversely correlated
             with speed, stride length, and knee range of motion at both
             speeds and PVF at the fast speed. The WOMAC function score
             was inversely correlated with speed and stride length at
             both speeds and with PVF at fast speed. The WOMAC pain score
             was inversely correlated with speed and PVF at the fast
             speed. Regression analysis revealed that the AIMS physical
             disability score and body mass index accounted for the
             greatest variation in speed at the normal speed. Overall,
             AIMS physical disability and WOMAC function explained a
             larger proportion of variance in gait mechanics than
             radiographic measures of OA disease severity. CONCLUSIONS:
             Taken together, the results suggest that the AIMS physical
             disability and WOMAC function scores are associated with
             some important measures of gait impairment.},
   Language = {eng},
   Doi = {10.1016/j.apmr.2009.07.010},
   Key = {fds241091}
}

@article{fds241099,
   Author = {Somers, TJ and Keefe, FJ and Pells, JJ and Dixon, KE and Waters, SJ and Riordan, PA and Blumenthal, JA and McKee, DC and LaCaille, L and Tucker,
             JM and Schmitt, D and Caldwell, DS and Kraus, VB and Sims, EL and Shelby,
             RA and Rice, JR},
   Title = {Pain catastrophizing and pain-related fear in osteoarthritis
             patients: relationships to pain and disability.},
   Journal = {Journal of Pain and Symptom Management},
   Volume = {37},
   Number = {5},
   Pages = {863-872},
   Year = {2009},
   Month = {May},
   ISSN = {1873-6513},
   url = {http://www.ncbi.nlm.nih.gov/pubmed/19041218},
   Keywords = {Activities of Daily Living* • Anxiety •
             Comorbidity • Disability Evaluation* • Fear*
             • Female • Humans • Male • Middle Aged
             • North Carolina • Osteoarthritis, Knee •
             Pain • Risk Assessment • Risk Factors •
             diagnosis • epidemiology • epidemiology* •
             methods • psychology},
   Abstract = {This study examined the degree to which pain catastrophizing
             and pain-related fear explain pain, psychological
             disability, physical disability, and walking speed in
             patients with osteoarthritis (OA) of the knee. Participants
             in this study were 106 individuals diagnosed as having OA of
             at least one knee, who reported knee pain persisting for six
             months or longer. Results suggest that pain catastrophizing
             explained a significant proportion (all Ps < or = 0.05) of
             variance in measures of pain (partial r(2) [pr(2)] = 0.10),
             psychological disability (pr(2) = 0.20), physical disability
             (pr(2) = 0.11), and gait velocity at normal (pr(2) = 0.04),
             fast (pr(2) = 0.04), and intermediate speeds (pr(2) = 0.04).
             Pain-related fear explained a significant proportion of the
             variance in measures of psychological disability (pr(2) =
             0.07) and walking at a fast speed (pr(2) = 0.05). Pain
             cognitions, particularly pain catastrophizing, appear to be
             important variables in understanding pain, disability, and
             walking at normal, fast, and intermediate speeds in knee OA
             patients. Clinicians interested in understanding variations
             in pain and disability in this population may benefit by
             expanding the focus of their inquiries beyond traditional
             medical and demographic variables to include an assessment
             of pain catastrophizing and pain-related
             fear.},
   Language = {eng},
   Doi = {10.1016/j.jpainsymman.2008.05.009},
   Key = {fds241099}
}

@article{fds241082,
   Author = {Sims, EL and Carland, JM and Keefe, FJ and Kraus, VB and Guilak, F and Schmitt, D},
   Title = {Sex differences in biomechanics associated with knee
             osteoarthritis.},
   Journal = {Journal of Women & Aging},
   Volume = {21},
   Number = {3},
   Pages = {159-170},
   Year = {2009},
   Month = {January},
   ISSN = {1540-7322},
   url = {http://www.ncbi.nlm.nih.gov/pubmed/20183142},
   Keywords = {Adult • Aged • Biomechanics • Female •
             Humans • Imaging, Three-Dimensional • Male •
             Middle Aged • Osteoarthritis, Knee • Prevalence
             • Severity of Illness Index • Sex Distribution
             • epidemiology* • physiopathology*},
   Abstract = {Osteoarthritis of the knee is seen more frequently in
             females than males. However, few studies have examined the
             interplay of gender, gait mechanics, pain, and disability in
             persons with osteoarthritis. This study examines the
             influence of anthropometrics, radiographic disease severity,
             pain, and disability on gender differences in gait mechanics
             in patients with knee osteoarthritis. Gait mechanics for 26
             men and 30 women were collected using 3-D kinematics and
             kinetics. Women had a significantly lower knee adduction
             moment than men and a significantly higher stride frequency.
             Within female subjects, variations in gait mechanics were
             primarily explained by weight, BMI, pain, and disability. In
             males, variations in gait mechanics were primarily explained
             by age and disability.},
   Language = {eng},
   Doi = {10.1080/08952840903054856},
   Key = {fds241082}
}

@article{fds241100,
   Author = {Kivell, TL and Schmitt, D},
   Title = {Independent evolution of knuckle-walking in African apes
             shows that humans did not evolve from a knuckle-walking
             ancestor},
   Journal = {Proceedings of the National Academy of Sciences of the
             United States of America},
   Volume = {106},
   Number = {34},
   Pages = {14241-14246},
   Year = {2009},
   ISSN = {0027-8424},
   url = {http://dx.doi.org/10.1073/pnas.0901280106},
   Keywords = {Animals • Anthropology, Physical • Biological
             Evolution* • Fossils • Hominidae • Humans
             • Walking • Wrist Joint • anatomy & histology
             • physiology • physiology*},
   Abstract = {Despite decades of debate, it remains unclear whether human
             bipedalism evolved from a terrestrial knuckle-walking
             ancestor or from a more generalized, arboreal ape ancestor.
             Proponents of the knuckle-walking hypothesis focused on the
             wrist and hand to find morphological evidence of this
             behavior in the human fossil record. These studies, however,
             have not examined variation or development of purported
             knuckle-walking features in apes or other primates, data
             that are critical to resolution of this long-standing
             debate. Here we present novel data on the frequency and
             development of putative knuckle-walking features of the
             wrist in apes and monkeys. We use these data to test the
             hypothesis that all knuckle-walking apes share similar
             anatomical features and that these features can be used to
             reliably infer locomotor behavior in our extinct ancestors.
             Contrary to previous expectations, features long-assumed to
             indicate knuckle-walking behavior are not found in all
             African apes, show different developmental patterns across
             species, and are found in nonknuckle-walking primates as
             well. However, variation among African ape wrist morphology
             can be clearly explained if we accept the likely independent
             evolution of 2 fundamentally different biomechanical modes
             of knuckle-walking: an extended wrist posture in an arboreal
             environment (Pan) versus a neutral, columnar hand posture in
             a terrestrial environment (Gorilla). The presence of
             purported knuckle-walking features in the hominin wrist can
             thus be viewed as evidence of arboreality, not
             terrestriality, and provide evidence that human bipedalism
             evolved from a more arboreal ancestor occupying the
             ecological niche common to all living apes.},
   Language = {eng},
   Doi = {10.1073/pnas.0901280106},
   Key = {fds241100}
}

@article{fds241097,
   Author = {Pells, JJ and Shelby, RA and Keefe, FJ and Dixon, KE and Blumenthal, JA and Lacaille, L and Tucker, JM and Schmitt, D and Caldwell, DS and Kraus,
             VB},
   Title = {Arthritis self-efficacy and self-efficacy for resisting
             eating: relationships to pain, disability, and eating
             behavior in overweight and obese individuals with
             osteoarthritic knee pain.},
   Journal = {Pain},
   Volume = {136},
   Number = {3},
   Pages = {340-347},
   Year = {2008},
   Month = {June},
   ISSN = {1872-6623},
   url = {http://www.ncbi.nlm.nih.gov/pubmed/17764844},
   Keywords = {Arthralgia • Comorbidity • Disability Evaluation
             • Employment • Feeding Behavior* • Female
             • Humans • Male • Middle Aged • North
             Carolina • Obesity • Osteoarthritis, Knee •
             Overweight • Prevalence • Prognosis • Risk
             Assessment • Self Efficacy* • epidemiology •
             epidemiology* • methods* • prevention & control
             • statistics & numerical data},
   Abstract = {This study examined arthritis self-efficacy and
             self-efficacy for resisting eating as predictors of pain,
             disability, and eating behaviors in overweight or obese
             patients with osteoarthritis (OA) of the knee. Patients
             (N=174) with a body mass index between 25 and 42 completed
             measures of arthritis-related self-efficacy, weight-related
             self-efficacy, pain, physical disability, psychological
             disability, overeating, and demographic and medical
             information. Hierarchical linear regression analyses were
             conducted to examine whether arthritis self-efficacy
             (efficacy for pain control, physical function, and other
             symptoms) and self-efficacy for resisting eating accounted
             for significant variance in pain, disability, and eating
             behaviors after controlling for demographic and medical
             characteristics. Analyses also tested whether the
             contributions of self-efficacy were domain specific. Results
             showed that self-efficacy for pain accounted for 14% (p=.01)
             of the variance in pain, compared to only 3% accounted for
             by self-efficacy for physical function and other symptoms.
             Self-efficacy for physical function accounted for 10%
             (p=.001) of the variance in physical disability, while
             self-efficacy for pain and other symptoms accounted for 3%.
             Self-efficacy for other (emotional) symptoms and resisting
             eating accounted for 21% (p<.05) of the variance in
             psychological disability, while self-efficacy for pain
             control and physical function were not significant
             predictors. Self-efficacy for resisting eating accounted for
             28% (p=.001) of the variance in eating behaviors. Findings
             indicate that self-efficacy is important in understanding
             pain and behavioral adjustment in overweight or obese OA
             patients. Moreover, the contributions of self-efficacy were
             domain specific. Interventions targeting both arthritis
             self-efficacy and self-efficacy for resisting eating may be
             helpful in this population.},
   Language = {eng},
   Doi = {10.1016/j.pain.2007.07.012},
   Key = {fds241097}
}

@article{fds241078,
   Author = {Bishop, KL and Pai, AK and Schmitt, D},
   Title = {Whole body mechanics of stealthy walking in
             cats},
   Journal = {Plos One},
   Volume = {3},
   Number = {11},
   Pages = {e3808},
   Year = {2008},
   ISSN = {1932-6203},
   url = {http://hdl.handle.net/10161/4508 Duke open
             access},
   Keywords = {Animals • Cats • Energy Metabolism • Gait
             • Locomotion • Mechanics • Walking •
             physiology*},
   Abstract = {The metabolic cost associated with locomotion represents a
             significant part of an animal's metabolic energy budget.
             Therefore understanding the ways in which animals manage the
             energy required for locomotion by controlling muscular
             effort is critical to understanding limb design and the
             evolution of locomotor behavior. The assumption that
             energetic economy is the most important target of natural
             selection underlies many analyses of steady animal
             locomotion, leading to the prediction that animals will
             choose gaits and postures that maximize energetic
             efficiency. Many quadrupedal animals, particularly those
             that specialize in long distance steady locomotion, do in
             fact reduce the muscular contribution required for walking
             by adopting pendulum-like center of mass movements that
             facilitate exchange between kinetic energy (KE) and
             potential energy (PE) [1-4]. However, animals that are not
             specialized for long distance steady locomotion may face a
             more complex set of requirements, some of which may conflict
             with the efficient exchange of mechanical energy. For
             example, the "stealthy" walking style of cats may demand
             slow movements performed with the center of mass close to
             the ground. Force plate and video data show that domestic
             cats (Felis catus, Linnaeus, 1758) have lower mechanical
             energy recovery than mammals specialized for distance. A
             strong negative correlation was found between mechanical
             energy recovery and diagonality in the footfalls and there
             was also a negative correlation between limb compression and
             diagonality of footfalls such that more crouched postures
             tended to have greater diagonality. These data show a
             previously unrecognized mechanical relationship in which
             crouched postures are associated with changes in footfall
             pattern which are in turn related to reduced mechanical
             energy recovery. Low energy recovery was not associated with
             decreased vertical oscillations of the center of mass as
             theoretically predicted, but rather with posture and
             footfall pattern on the phase relationship between potential
             and kinetic energy. An important implication of these
             results is the possibility of a tradeoff between stealthy
             walking and economy of locomotion. This potential tradeoff
             highlights the complex and conflicting pressures that may
             govern the locomotor choices that animals make. © 2008
             Bishop et al.},
   Language = {eng},
   Doi = {10.1371/journal.pone.0003808},
   Key = {fds241078}
}

@article{fds241098,
   Author = {Hanna, JB and Schmitt, D and Griffin, TM},
   Title = {The energetic cost of climbing in primates},
   Journal = {Science (New York, N.Y.)},
   Volume = {320},
   Number = {5878},
   Pages = {898-},
   Year = {2008},
   ISSN = {0036-8075},
   url = {http://dx.doi.org/10.1126/science.1155504},
   Keywords = {Animals • Biomechanics • Body Size • Body
             Weight • Energy Metabolism* • Locomotion •
             Lorisidae • Oxygen Consumption • Saimiri •
             Strepsirhini • Walking • physiology*},
   Abstract = {Primates are exceptional among mammals for their climbing
             abilities and arboreal lifestyles. Here we show that small
             primates (less than 0.5 kilogram) consume the same amount of
             mass-specific energy (COTTOT) whether climbing or walking a
             given distance. COTTOT decreases with increasing body size
             for walking but does not change for climbing. This
             divergence of COTTOT is likely due to fundamental
             differences in the biomechanical determinants of the costs
             of climbing versus walking. These results have important
             implications for understanding the origins of primates,
             suggesting that small early primates may have been able to
             move into a novel arboreal niche without increasing
             metabolic costs.},
   Language = {eng},
   Doi = {10.1126/science.1155504},
   Key = {fds241098}
}

@article{fds241063,
   Author = {Cartmill, M and Lemelin, P and Schmitt, D},
   Title = {Primate gaits and primate origins},
   Pages = {403-435},
   Booktitle = {Primate Origins},
   Publisher = {Springer US},
   Editor = {M. Dagosto and M. Ravosa},
   Year = {2007},
   Month = {December},
   url = {http://dx.doi.org/10.1007/978-0-387-33507-0_12},
   Doi = {10.1007/978-0-387-33507-0_12},
   Key = {fds241063}
}

@article{fds241064,
   Author = {Lemelin, P and Schmitt, D},
   Title = {Origins of grasping and locomotor adaptations in primates:
             Comparative and experimental approaches using an opossum
             model},
   Pages = {329-380},
   Publisher = {Springer US},
   Year = {2007},
   Month = {December},
   url = {http://dx.doi.org/10.1007/978-0-387-33507-0_10},
   Abstract = {Since the turn of the 20th century, most anthropologists
             agreed on one fundamental notion: the origin and evolution
             of the order Primates was closely tied with life in the
             trees. This view is founded on the obvious observation that
             the vast majority of extant primates live in the trees and
             have colonized many different arboreal habitats. Smith
             (1912) and Jones (1916) were among the first to relate some
             of the unique anatomical and behavioral characteristics of
             primates with arboreal life. Their views were promoted by
             LeGros Clark (1959), but later challenged and refined by
             Cartmill (1972, 1974a,b) who suggested that the
             forward-facing eyes and grasping extremities of primates can
             be interpreted as adaptations to cautious foraging for
             insect prey on thin, flexible branches. At the same time,
             Jenkins (1974: 112) suggested that "The adaptive innovation
             of ancestral primates was therefore not the invasion of the
             arboreal habitat, but their successful restriction to it."
             However, there are several extant mammal species other than
             primates that are restricted to an arboreal environment,
             particularly in which thin and flexible branches abound. As
             Cartmill (1972, 1974a,b) and Ramussen (1990) stressed, those
             nonprimate mammals offer great potential in addressing the
             problem of primate origins. The views of Jenkins and
             Cartmill had a profound influence on the adaptive
             explanations of the postcranial and locomotor features that
             define primates as a group. Several primate postcranial and
             locomotor characteristics, rare in other mammals, are now
             being interpreted as evidence of an invasion and restriction
             to a fine-branch, arboreal niche by the earliest primates.
             For example, primates have prehensile hands and feet that
             bear nails instead of sharp claws (Cartmill, 1970, 1972,
             1974a,b, 1985; Jones, 1916, 1929; LeGros Clark, 1959;
             Lemelin, 1996; Martin, 1968, 1986, 1990; Mivart, 1873;
             Napier, 1961, 1993; Napier and Napier, 1967; Szalay and
             Dagosto, 1988; Szalay et al., 1987) and relatively long
             limbs (Alexander et al., 1979; Polk et al., 2000) with more
             mobile joints, particularly in the forelimbs (Reynolds,
             1985b). In addition to these postcranial features, most
             primates share three locomotor characteristics that are
             unusual or unique compared to other mammals (Larson, 1998).
             During quadrupedal walking, primates are characterized by:
             (a) an almost exclusive use of diagonal-sequence (DS)
             walking gaits (i.e., each hind footfall is followed by the
             contralateral fore footfall) (Cartmill et al., 2002;
             Hildebrand, 1967, 1985; Rollinson and Martin, 1981; Vilensky
             and Larson, 1989); (b) a protracted arm position at forelimb
             touchdown (i.e., arm greater than 90 relative to horizontal
             body axis) (Larson, 1998; Larson et al., 2000, 2001); (c)
             relatively lower peak vertical substrate reaction forces
             (Vpk) on the forelimbs compared to the hindlimbs (Demes et
             al., 1994; Kimura et al., 1979; Reynolds, 1985b); and (d)
             forelimb compliance (Larney and Larson 2004; Schmitt, 1998,
             1999, 2003a,b; Schmitt and Hanna, 2004). What has been
             lacking is a clear demonstration that mammals restricted to
             a fine-branch environment possess similar postcranial and
             locomotor characteristics that are functionally linked to
             moving and foraging on thin arboreal supports. In this
             chapter, we present the results of comparative and
             experimental studies that test the relationship between the
             presence of primate-like features and fine-branch
             arborealism using ecological convergence between didelphid
             marsupials and prosimian primates. Following a review of
             various models of primates, we present morphometric and
             behavioral data for opossums and primates that test
             specifically the functional link between the presence of
             more grasping, primate-like cheiridia and movement on thin
             branches. In the second part, we report experimental results
             that specifically test for the presence of three gait
             characteristics typical of most primates in a fine-branch
             arborealist, the woolly opossum (Caluromys philander). In
             the last part of this chapter, we discuss how these data
             accord with current theories of primate origins and assess
             the relevance of an opossum model in inferring the locomotor
             profile and ecological niche of the earliest primates. ©
             Springer Science+Business Media, LLC 2007.},
   Doi = {10.1007/978-0-387-33507-0_10},
   Key = {fds241064}
}

@article{fds241090,
   Author = {Hutchinson, D and Ho, V and Dodd, M and Dawson, HN and Zumwalt, AC and Schmitt, D and Colton, CA},
   Title = {Quantitative measurement of postural sway in mouse models of
             human neurodegenerative disease.},
   Journal = {Neuroscience},
   Volume = {148},
   Number = {4},
   Pages = {825-832},
   Year = {2007},
   Month = {September},
   ISSN = {0306-4522},
   url = {http://www.ncbi.nlm.nih.gov/pubmed/17764851},
   Keywords = {Age Factors • Amyloid beta-Protein Precursor •
             Animals • Animals, Newborn • Behavior, Animal
             • Biomechanics • Disease Models, Animal* •
             Female • Harmaline • Humans • Male •
             Mice • Mice, Inbred C57BL • Mice, Transgenic
             • Monoamine Oxidase Inhibitors • Motor Activity
             • Mutation • Neurodegenerative Diseases •
             Nitric Oxide Synthase Type II • Postural Balance •
             Posture • Tremor • adverse effects •
             chemically induced • drug effects • genetics
             • methods • physiology • physiology* •
             physiopathology • physiopathology*},
   Abstract = {Detection of motor dysfunction in genetic mouse models of
             neurodegenerative disease requires reproducible,
             standardized and sensitive behavioral assays. We have
             utilized a center of pressure (CoP) assay in mice to
             quantify postural sway produced by genetic mutations that
             affect motor control centers of the brain. As a positive
             control for postural instability, wild type mice were
             injected with harmaline, a tremorigenic agent, and the
             average areas of the 95% confidence ellipse, which measures
             95% of the CoP trajectory values recorded in a single trial,
             were measured. Ellipse area significantly increased in mice
             treated with increasing doses of harmaline and returned to
             control values after recovery. We also examined postural
             sway in mice expressing mutations that mimic frontotemporal
             dementia with Parkinsonism linked to chromosome 17 (FTDP-17)
             (T-279, P301L or P301L-nitric oxide synthase 2 (NOS2)(-/-)
             mice) and that demonstrate motor symptoms. These mice were
             then compared with a mouse model of Alzheimer's disease
             (APPSwDI mice) that demonstrates cognitive, but not motor
             deficits. T-279 and P301L-NOS2(-/-) mice demonstrated a
             significant increase in CoP ellipse area compared with
             appropriate wild type control mice or to mice expressing the
             P301L mutation alone. In contrast, postural instability was
             significantly reduced in APPSwDI mice that have cognitive
             deficits but do not have associated motor deficits. The CoP
             assay provides a simple, sensitive and quantitative tool to
             detect motor deficits resulting from postural abnormalities
             in mice and may be useful in understanding the underlying
             mechanisms of disease.},
   Language = {eng},
   Doi = {10.1016/j.neuroscience.2007.07.025},
   Key = {fds241090}
}

@article{fds241101,
   Author = {Cartmill, M and Lemelin, P and Schmitt, D},
   Title = {Understanding the adaptive value of diagonal-sequence gaits
             in primates: a comment on Shapiro and Raichlen,
             2005.},
   Journal = {American Journal of Physical Anthropology},
   Volume = {133},
   Number = {2},
   Pages = {822-825},
   Year = {2007},
   Month = {June},
   ISSN = {0002-9483},
   url = {http://www.ncbi.nlm.nih.gov/pubmed/17427929},
   Keywords = {Adaptation, Physiological* • Animals • Animals,
             Newborn • Anthropology, Physical* • Biological
             Evolution • Biomechanics • Gait • Primates
             • Species Specificity • Walking • physiology
             • physiology*},
   Abstract = {This study examined arthritis self-efficacy and
             self-efficacy for resisting eating as predictors of pain,
             disability, and eating behaviors in overweight or obese
             patients with osteoarthritis (OA) of the knee. Patients
             (N=174) with a body mass index between 25 and 42 completed
             measures of arthritis-related self-efficacy, weight-related
             self-efficacy, pain, physical disability, psychological
             disability, overeating, and demographic and medical
             information. Hierarchical linear regression analyses were
             conducted to examine whether arthritis self-efficacy
             (efficacy for pain control, physical function, and other
             symptoms) and self-efficacy for resisting eating accounted
             for significant variance in pain, disability, and eating
             behaviors after controlling for demographic and medical
             characteristics. Analyses also tested whether the
             contributions of self-efficacy were domain specific. Results
             showed that self-efficacy for pain accounted for 14% (p=.01)
             of the variance in pain, compared to only 3% accounted for
             by self-efficacy for physical function and other symptoms.
             Self-efficacy for physical function accounted for 10%
             (p=.001) of the variance in physical disability, while
             self-efficacy for pain and other symptoms accounted for 3%.
             Self-efficacy for other (emotional) symptoms and resisting
             eating accounted for 21% (p<.05) of the variance in
             psychological disability, while self-efficacy for pain
             control and physical function were not significant
             predictors. Self-efficacy for resisting eating accounted for
             28% (p=.001) of the variance in eating behaviors. Findings
             indicate that self-efficacy is important in understanding
             pain and behavioral adjustment in overweight or obese OA
             patients. Moreover, the contributions of self-efficacy were
             domain specific. Interventions targeting both arthritis
             self-efficacy and self-efficacy for resisting eating may be
             helpful in this population.},
   Language = {eng},
   Doi = {10.1002/ajpa.20589},
   Key = {fds241101}
}

@article{fds241107,
   Author = {Schmitt, D and Cartmill, M and Griffin, TM and Hanna, JB and Lemelin,
             P},
   Title = {Adaptive value of ambling gaits in primates and other
             mammals.},
   Journal = {The Journal of Experimental Biology},
   Volume = {209},
   Number = {Pt 11},
   Pages = {2042-2049},
   Year = {2006},
   Month = {June},
   ISSN = {0022-0949},
   url = {http://www.ncbi.nlm.nih.gov/pubmed/16709907},
   Keywords = {Adaptation, Physiological • Animals • Gait •
             Locomotion • Models, Biological • Primates •
             Species Specificity • anatomy & histology •
             physiology • physiology*},
   Abstract = {At speeds between the walk and the gallop, most mammals
             trot. Primates almost never trot, and it has been claimed
             that they transition directly from a walk to a gallop
             without any distinctive mid-speed running gait. If true,
             this would be another characteristic difference between the
             locomotion of primates and that of most other quadrupedal
             mammals. Presently, however, few data exist concerning the
             actual presence or absence of intermediate-speed gaits (i.e.
             gaits that are used between a walk and a gallop) in
             primates. Video records of running in twelve primate species
             reveal that, unlike most other mammals, all the primates
             studied almost exclusively adopt an 'amble'--an
             intermediate-speed running gait with no whole-body aerial
             phase--rather than trot. Ambling is also common in elephants
             and some horses, raising the question of why ambling is
             preferred over trotting in these diverse groups of animals.
             Mathematical analyses presented here show that ambling
             ensures continuous contact of the body with the substrate
             while dramatically reducing vertical oscillations of the
             center of mass. This may explain why ambling appears to be
             preferable to trotting for extremely large terrestrial
             mammals such as elephants and for arboreal mammals like
             primates that move on unstable branches. These findings
             allow us to better understand the mechanics of these unusual
             running gaits and shed new light on primate locomotor
             evolution.},
   Language = {eng},
   Doi = {10.1242/jeb.02235},
   Key = {fds241107}
}

@article{fds201335,
   Author = {JB Hanna},
   Title = {Kinematics of vertical climbing in lorises and Cheirogaleus
             medius.},
   Journal = {Journal of human evolution},
   Volume = {50},
   Number = {4},
   Pages = {469-78},
   Year = {2006},
   Month = {April},
   ISSN = {0047-2484},
   url = {http://dx.doi.org/10.1016/j.jhevol.2005.12.001},
   Keywords = {Adaptation, Physiological • Animals • Biomechanics
             • Cheirogaleidae • Hip • Leg •
             Locomotion • Lorisidae • Species Specificity
             • Thigh • classification • physiology •
             physiology*},
   Abstract = {The type of climbing exhibited by apes and atelines is
             argued to have been important in the evolution of
             specialized locomotion, such as suspensory locomotion and
             bipedalism. However, little is known about the mechanics of
             climbing in primates. Previous work shows that Asian apes
             and atelines use larger joint excursions and longer strides
             than African apes and the Japanese macaque, respectively.
             This study expands knowledge of climbing mechanics by
             providing the first quantitative kinematic data for vertical
             climbing in four prosimian species: three lorisid species
             (Loris tardigradus, Nycticebus coucang, and Nycticebus
             pygmaeus) that share with apes and atelines morphological
             traits arguably related to climbing, and a more generalized
             quadruped, Cheirogaleus medius. Subjects were videotaped as
             they climbed up a wooden pole. Kinematic values, such as
             step length and limb excursions, were calculated and
             compared between species. The results of this study show
             that lorises, like Asian apes and spider monkeys, use
             relatively larger joint excursions and longer steps than
             does C. medius during climbing. These data lend further
             support to the idea that some primate species (e.g.,
             lorises, atelines, and apes) are more specialized
             kinematically and morphologically for climbing than others.
             Pilot data suggest that such kinematic differences in
             climbing style across broad phylogenetic groups may relate
             to the energetics of climbing. Such data may be important
             for understanding the morphological and kinematic
             adaptations to climbing exhibited by some
             primates.},
   Language = {eng},
   Doi = {10.1016/j.jhevol.2005.12.001},
   Key = {fds201335}
}

@article{fds241108,
   Author = {Zumwalt, AC and Hamrick, M and Schmitt, D},
   Title = {Force plate for measuring the ground reaction forces in
             small animal locomotion.},
   Journal = {Journal of Biomechanics},
   Volume = {39},
   Number = {15},
   Pages = {2877-2881},
   Year = {2006},
   Month = {January},
   ISSN = {0021-9290},
   url = {http://dx.doi.org/10.1016/j.jbiomech.2005.10.006},
   Keywords = {Animals • Biomechanics • Data Collection •
             Equipment Design • Forelimb • Hindlimb •
             Locomotion • Mice • Musculoskeletal Physiological
             Phenomena • Physiology • Postural Balance •
             instrumentation* • methods • physiology •
             physiology*},
   Abstract = {The importance of kinetic force plate studies of locomotion
             in small animals has grown recently with the increasing use
             of rodent models for studies of musculoskeletal diseases.
             However, the force plates for use with animals much smaller
             than a cat are difficult to design and use. Here we present
             data on a commercially available small force plate that
             accurately collects whole-body and, in a modified form,
             single-limb ground reaction forces in mice. The method used
             here is convenient, inexpensive, and readily adaptable for
             use with a variety of small species.},
   Language = {eng},
   Doi = {10.1016/j.jbiomech.2005.10.006},
   Key = {fds241108}
}

@article{fds241106,
   Author = {Hanna, JB and Polk, JD and Schmitt, D},
   Title = {Forelimb and hindlimb forces in walking and galloping
             primates},
   Journal = {American Journal of Physical Anthropology},
   Volume = {130},
   Number = {4},
   Pages = {529-535},
   Year = {2006},
   ISSN = {0002-9483},
   url = {http://dx.doi.org/10.1002/ajpa.20385},
   Keywords = {Animals • Callithrix • Cercopithecus aethiops
             • Cheirogaleidae • Erythrocebus patas •
             Female • Forelimb • Gait • Hindlimb •
             Kinetics • Locomotion • Macaca mulatta • Male
             • Papio anubis • Primates • Videotape
             Recording • Walking • Weight-Bearing •
             physiology • physiology*},
   Abstract = {One trait that distinguishes the walking gaits of most
             primates from those of most mammalian nonprimates is the
             distribution of weight between the forelimbs and hindlimbs.
             Nonprimate mammals generally experience higher vertical peak
             substrate reaction forces on the forelimb than on the
             hindlimb. Primates, in contrast, generally experience higher
             vertical peak substrate reaction forces on the hindlimb than
             on the forelimb. It is currently unclear whether this
             unusual pattern of force distribution characterizes other
             primate gaits as well. The available kinetic data for
             galloping primates are limited and present an ambiguous
             picture about peak-force distribution among the limbs. The
             present study investigates whether the pattern of
             forelimb-to-hindlimb force distribution seen during walking
             in primates is also displayed during galloping. Six species
             of primates were video-recorded during walking and galloping
             across a runway or horizontal pole instrumented with a
             force-plate. The results show that while the force
             differences between forelimb and hindlimb are not
             significantly different from zero during galloping, the
             pattern of force distribution is generally the same during
             walking and galloping for most primate species. These
             patterns and statistical results are similar to data
             collected during walking on the ground. The pattern of limb
             differentiation exhibited by primates during walking and
             galloping stands in contrast to the pattern seen in most
             nonprimate mammals, in which forelimb forces are
             significantly higher. The data reported here and by Demes et
             al. ([1994] J. Hum. Evol. 26:353-374) suggest that a
             relative reduction of forelimb vertical peak forces is part
             of an overall difference in locomotor mechanics between most
             primates and most nonprimate mammals during both walking and
             galloping. © 2006 Wiley-Liss, Inc.},
   Language = {eng},
   Doi = {10.1002/ajpa.20385},
   Key = {fds241106}
}

@article{fds241109,
   Author = {Stevens, NJ and Schmitt, DO and III, TMC and Chan,
             L-K},
   Title = {Technical note: Out-of-plane angular correction based on a
             trigonometric function for use in two-dimensional kinematic
             studies},
   Journal = {American Journal of Physical Anthropology},
   Volume = {129},
   Number = {3},
   Pages = {399-402},
   Year = {2006},
   ISSN = {0002-9483},
   url = {http://dx.doi.org/10.1002/ajpa.20359},
   Keywords = {Biomechanics • Extremities* • Mathematics* •
             Models, Theoretical* • methods*},
   Abstract = {In two-dimensional (2D) kinematic studies, limb positions in
             three-dimensional (3D) space observed in lateral view are
             projected onto a 2D film plane. Elbow and knee-joint angles
             that are less than 20° out-of-plane of lateral-view cameras
             generally exhibit very little measurable difference from
             their 3D counterparts (Plagenhoef [1979] Environment,
             Behavior, and Morphology; New York: Gustav Fisher, p.
             95-118). However, when limb segment angles are more than
             20° out-of-plane, as is often the case in locomotor studies
             of arboreal primates, elbow and knee angles can appear
             significantly more extended than they actually are. For this
             reason, a methodology is described that corrects 2D
             out-of-plane angular estimates using a series of
             trigonometric transformations. © 2005 Wiley-Liss,
             Inc.},
   Language = {eng},
   Doi = {10.1002/ajpa.20359},
   Key = {fds241109}
}

@article{fds241104,
   Author = {Schmitt, D and Rose, MD and Turnquist, JE and Lemelin,
             P},
   Title = {Role of the prehensile tail during ateline locomotion:
             Experiment and osteological evidence},
   Journal = {American Journal of Physical Anthropology},
   Volume = {126},
   Number = {4},
   Pages = {435-446},
   Year = {2005},
   ISSN = {0002-9483},
   url = {http://dx.doi.org/10.1002/ajpa.20075},
   Keywords = {Animals • Anthropometry • Biomechanics • Bone
             and Bones • Cebidae • Locomotion • Muscle,
             Skeletal • Species Specificity • Tail •
             anatomy & histology • anatomy & histology* •
             physiology*},
   Abstract = {The dynamic role of the prehensile tail of atelines during
             locomotion is poorly understood. While some have viewed the
             tail of Ateles simply as a safety mechanism, others have
             suggested that the prehensile tail plays an active role by
             adjusting pendulum length or controlling lateral sway during
             bimanual suspensory locomotion. This study examines the bony
             and muscular anatomy of the prehensile tail as well as the
             kinematics of tail use during tail-assisted brachiation in
             two primates, Ateles and Lagothrix. These two platyrrhines
             differ in anatomy and in the frequency and kinematics of
             suspensory locomotion. Lagothrix is stockier, has shorter
             forelimbs, and spends more time traveling quadrupedally and
             less time using bimanual suspensory locomotion than does
             Ateles. In addition, previous studies showed that Ateles
             exhibits greater hyperextension of the tail, uses its tail
             to grip only on alternate handholds, and has a larger
             abductor caudae medialis muscle compared to Lagothrix. In
             order to investigate the relationship between anatomy and
             behavior concerning the prehensile tail, osteological data
             and kinematic data were collected for Ateles fusciceps and
             Lagothrix lagothricha. The results demonstrate that Ateles
             has more numerous and smaller caudal elements, particularly
             in the proximal tail region. In addition, transverse
             processes are relatively wider, and sacro-caudal
             articulation is more acute in Ateles compared to Lagothrix.
             These differences reflect the larger abductor muscle mass
             and greater hyperextension in Ateles. In addition, Ateles
             shows fewer side-to-side movements during tail-assisted
             brachiation than does Lagothrix. These data support the
             notion that the pre3hensile tail represents a critical
             dynamic element in the tail-assisted brachiation of Ateles,
             and may be useful in developing inferences concerning
             behavior in fossil primates. © 2004 Wiley-Liss,
             Inc.},
   Language = {eng},
   Doi = {10.1002/ajpa.20075},
   Key = {fds241104}
}

@article{fds241105,
   Author = {Chi, K-J and Schmitt, D},
   Title = {Mechanical energy and effective foot mass during impact
             loading of walking and running},
   Journal = {Journal of Biomechanics},
   Volume = {38},
   Number = {7},
   Pages = {1387-1395},
   Year = {2005},
   ISSN = {0021-9290},
   url = {http://dx.doi.org/10.1016/j.jbiomech.2004.06.020},
   Keywords = {Computer Simulation • Connective Tissue •
             Elasticity • Energy Transfer • Foot • Gait
             • Heel • Humans • Models, Biological* •
             Posture • Running • Stress, Mechanical •
             Walking • physiology • physiology*},
   Abstract = {The human heel pad is considered an important structure for
             attenuation of the transient force caused by heel-strike.
             Although the mechanical properties of heel pads are
             relatively well understood, the mechanical energy (E tot)
             absorbed by the heel pad during the impact phase has never
             been documented directly because data on the effective foot
             mass (Meff) was previously unavailable during normal forward
             locomotion. In this study, we use the impulse-momentum
             method (IMM) for calculating Meff from moving subjects.
             Mass-spring-damper models were developed to evaluate errors
             and to examine the effects of pad property, upper body mass,
             and effective leg spring on Meff. We simultaneously
             collected ground reaction forces, pad deformation, and lower
             limb kinematics during impact phase of barefoot walking,
             running, and crouched walking. The latter was included to
             examine the effect of knee angle on Meff. The magnitude of
             Meff as a percentage of body mass (MB) varies with knee
             angle at impact and significantly differs among gaits:
             6.3%MB in walking, 5.3%M B in running, and 3.7%MB in
             crouched walking. Our modeling results suggested that Meff
             is insensitive to heel pad resilience and effective leg
             stiffness. At the instant prior to heel strike, E tot ranges
             from 0.24 to 3.99 J. The combination of video and forceplate
             data used in this study allows analyses of Etot and E tot as
             a function of heel-strike kinematics during normal
             locomotion. Relationship between Meff and knee angle
             provides insights into how changes in posture moderate
             impact transients at different gaits. © 2004 Elsevier Ltd.
             All rights reserved.},
   Language = {eng},
   Doi = {10.1016/j.jbiomech.2004.06.020},
   Key = {fds241105}
}

@article{fds53025,
   Author = {CJ Vinyard and D Schmitt},
   Title = {New technique for studying reaction forces during primate
             behaviors on vertical substrates.},
   Journal = {American journal of physical anthropology},
   Volume = {125},
   Number = {4},
   Pages = {343-51},
   Year = {2004},
   Month = {December},
   ISSN = {0002-9483},
   url = {http://dx.doi.org/10.1002/ajpa.10395},
   Keywords = {Animals • Biomechanics • Biophysics •
             Ergometry • Motor Activity • Primates •
             instrumentation • instrumentation* • methods*
             • physiology*},
   Abstract = {Recording reaction forces from primates during behaviors on
             vertical substrates, such as leaping, climbing, or biting
             trees, typically requires the design and construction of
             customized recording devices or mounting commercially
             available force platforms in a vertical position. The
             technical difficulties imposed by either option have
             hindered in vivo research on the kinetics of primate
             behaviors on vertical substrates. We describe a simple,
             inexpensive apparatus for recording forces from primate
             behaviors on vertical substrates. The apparatus includes an
             instrumented beam fastened directly to a horizontal force
             platform and a surrounding vertical substrate that does not
             contact the instrumented beam or platform. The contact piece
             at the end of the instrumented beam is positioned flush with
             the noninstrumented vertical substrate, and reaction forces
             elicited on this instrumented section are directed to the
             force platform. Because most of the vertical substrate is
             not instrumented, we can isolate and record forces from a
             single limb or jaw during a behavior. Biewener and Full
             ([1992] Biomechanics Structures and Positions: A Practical
             Approach; New York: Oxford University press, p. 45-73) gave
             seven criteria to consider when designing a customized
             force-recording device. Where appropriate, we tested if our
             apparatus met their criteria. The apparatus accurately
             records forces in three orthogonal directions, has low
             cross-talk, maintains a high frequency response, exhibits a
             linear response up to at least 200 Newtons, and displays a
             uniform response to a given force across the instrumented
             contact piece. Our design does not easily facilitate the
             identification of the point of force application. Therefore,
             joint moments cannot be easily calculated. This limitation,
             however, does not affect the apparatus's ability to
             accurately record the magnitude and direction of a force (as
             shown by other tests). We developed this apparatus to
             measure jaw forces during tree gouging in common marmosets
             (Callithrix jacchus), but the general design can be readily
             modified to study a variety of primate behaviors on vertical
             substrates.},
   Language = {eng},
   Doi = {10.1002/ajpa.10395},
   Key = {fds53025}
}

@article{fds53028,
   Author = {RF Kay and D Schmitt and CJ Vinyard and JM Perry and N Shigehara and M
             Takai, N Egi},
   Title = {The paleobiology of Amphipithecidae, South Asian late Eocene
             primates.},
   Journal = {Journal of human evolution},
   Volume = {46},
   Number = {1},
   Pages = {3-25},
   Year = {2004},
   Month = {January},
   ISSN = {0047-2484},
   url = {http://dx.doi.org/10.1016/j.jhevol.2003.11.008},
   Keywords = {Animals • Anthropology, Physical* • Behavior,
             Animal • Female • Fossils • Locomotion*
             • Male • Orbit • Primates • Skull •
             Tooth • anatomy & histology • anatomy &
             histology*},
   Abstract = {Analysis of the teeth, orbital, and gnathic regions of the
             skull, and fragmentary postcranial bones provides evidence
             for reconstructing a behavioral profile of Amphipithecidae:
             Pondaungia, Amphipithecus, Myanmarpithecus (late middle
             Eocene, Myanmar) and Siamopithecus (late Eocene, Thailand).
             At 5-8 kg, Pondaungia, Amphipithecus, and Siamopithecus are
             perhaps the largest known Eocene primates. The dental and
             mandibular anatomy suggest that large-bodied amphipithecids
             were hard-object feeders. The shape of the mandibular corpus
             and stiffened symphysis suggest an ability to resist large
             internal loads during chewing and to recruit significant
             amounts of muscle forces from both the chewing and
             non-chewing sides of the jaw so as to increase bite force
             during mastication. The large spatulate upper central
             incisor of Pondaungia and projecting robust canines of all
             the larger amphipithecids suggest that incisal food
             preparation was important. The molars of Siamopithecus,
             Amphipithecus, and Pondaungia have weak shearing crests.
             This, and the thick molar enamel found in Pondaungia,
             suggests a diet of seeds and other hard objects low in
             fiber. In contrast, Myanmarpithecus was smaller, about 1-2
             kg; its cheek teeth suggest a frugivorous diet and do not
             imply seed eating. Postcranial bones (humerus, ulna, and
             calcaneus) of a single large amphipithecid individual from
             Myanmar suggest an arboreal quadrupedal locomotor style like
             that of howler monkeys or lorises. The humeral head is
             rounded, proximally oriented, and the tuberosities are low
             indicating an extremely mobile glenohumeral joint. The great
             thickness of the midshaft cortical bone of the humerus
             implies enhanced ability to resist bending and torsion, as
             seen among slow moving primate quadrupeds. The elbow joint
             exhibits articular features for enhanced stability in
             habitually flexed positions, features also commonly found in
             slow moving arboreal quadrupeds. The short distal load arm
             of the calcaneus is consistent with, but not exclusive to,
             slow, arboreal quadrupedalism, and suggests no reliance on
             habitual leaping.},
   Language = {eng},
   Doi = {10.1016/j.jhevol.2003.11.008},
   Key = {fds53028}
}

@article{fds241121,
   Author = {Kay, RF and Schmitt, D and Vinyard, CJ and Perry, JMG and Shigehara, N and Takai, M and Egi, N},
   Title = {The paleobiology of Amphipithecidae, South Asian late Eocene
             primates.},
   Journal = {Journal of Human Evolution},
   Volume = {46},
   Number = {1},
   Pages = {3-25},
   Year = {2004},
   Month = {January},
   ISSN = {0047-2484},
   url = {http://www.ncbi.nlm.nih.gov/pubmed/14698683},
   Abstract = {Analysis of the teeth, orbital, and gnathic regions of the
             skull, and fragmentary postcranial bones provides evidence
             for reconstructing a behavioral profile of Amphipithecidae:
             Pondaungia, Amphipithecus, Myanmarpithecus (late middle
             Eocene, Myanmar) and Siamopithecus (late Eocene, Thailand).
             At 5-8 kg, Pondaungia, Amphipithecus, and Siamopithecus are
             perhaps the largest known Eocene primates. The dental and
             mandibular anatomy suggest that large-bodied amphipithecids
             were hard-object feeders. The shape of the mandibular corpus
             and stiffened symphysis suggest an ability to resist large
             internal loads during chewing and to recruit significant
             amounts of muscle forces from both the chewing and
             non-chewing sides of the jaw so as to increase bite force
             during mastication. The large spatulate upper central
             incisor of Pondaungia and projecting robust canines of all
             the larger amphipithecids suggest that incisal food
             preparation was important. The molars of Siamopithecus,
             Amphipithecus, and Pondaungia have weak shearing crests.
             This, and the thick molar enamel found in Pondaungia,
             suggests a diet of seeds and other hard objects low in
             fiber. In contrast, Myanmarpithecus was smaller, about 1-2
             kg; its cheek teeth suggest a frugivorous diet and do not
             imply seed eating. Postcranial bones (humerus, ulna, and
             calcaneus) of a single large amphipithecid individual from
             Myanmar suggest an arboreal quadrupedal locomotor style like
             that of howler monkeys or lorises. The humeral head is
             rounded, proximally oriented, and the tuberosities are low
             indicating an extremely mobile glenohumeral joint. The great
             thickness of the midshaft cortical bone of the humerus
             implies enhanced ability to resist bending and torsion, as
             seen among slow moving primate quadrupeds. The elbow joint
             exhibits articular features for enhanced stability in
             habitually flexed positions, features also commonly found in
             slow moving arboreal quadrupeds. The short distal load arm
             of the calcaneus is consistent with, but not exclusive to,
             slow, arboreal quadrupedalism, and suggests no reliance on
             habitual leaping.},
   Key = {fds241121}
}

@article{fds241077,
   Author = {Schmitt, D and Hanna, JB},
   Title = {Substrate alters forelimb to hindlimb peak force ratios in
             primates},
   Journal = {Journal of Human Evolution},
   Volume = {46},
   Number = {3},
   Pages = {239-254},
   Year = {2004},
   ISSN = {0047-2484},
   url = {http://dx.doi.org/10.1016/j.jhevol.2003.11.008},
   Keywords = {Animals • Arm • Cheirogaleidae • Female
             • Gait • Haplorhini • Leg • Male •
             Primates • Weight-Bearing • physiology •
             physiology*},
   Abstract = {It is often claimed that the walking gaits of primates are
             unusual because, unlike most other mammals, primates appear
             to have higher vertical peak ground reaction forces on their
             hindlimbs than on their forelimbs. Many researchers have
             argued that this pattern of ground reaction force
             distribution is part of a general adaptation to arboreal
             locomotion. This argument is frequently used to support
             models of primate locomotor evolution. Unfortunately, little
             is known about the force distribution patterns of primates
             walking on arboreal supports, nor do we completely
             understand the mechanisms that regulate weight distribution
             in primates. We collected vertical peak force data for seven
             species of primates walking quadrupedally on instrumented
             terrestrial and arboreal supports. Our results show that,
             when walking on arboreal vs. terrestrial substrates,
             primates generally have lower vertical peak forces on both
             limbs but the difference is most extreme for the forelimb.
             We found that force reduction occurs primarily by decreasing
             forelimb and, to a lesser extent, hindlimb stiffness. As a
             result, on arboreal supports, primates experience
             significantly greater functional differentiation of the
             forelimb and hindlimb than on the ground. These data support
             long-standing theories that arboreal locomotion was a
             critical factor in the differentiation of the forelimbs and
             hindlimbs in primates. This change in functional role of the
             forelimb may have played a critical role in the origin of
             primates and facilitated the evolution of more specialized
             locomotor behaviors. © 2003 Published by Elsevier
             Ltd.},
   Language = {eng},
   Doi = {10.1016/j.jhevol.2003.11.008},
   Key = {fds241077}
}

@article{fds241103,
   Author = {Schmitt, D and Lemelin, P},
   Title = {Locomotor mechanics of the slender loris (Loris
             tardigradus)},
   Journal = {Journal of Human Evolution},
   Volume = {47},
   Number = {1-2},
   Pages = {85-94},
   Year = {2004},
   ISSN = {0047-2484},
   url = {http://dx.doi.org/10.1016/j.jhevol.2004.05.006},
   Keywords = {Adaptation, Physiological • Animals •
             Anthropology, Physical • Biomechanics • Female
             • Lorisidae • Male • Posture • Trees
             • Video Recording • Walking •
             physiology*},
   Abstract = {The quadrupedal walking gaits of most primates can be
             distinguished from those of most other mammals by the
             presence of diagonal-sequence (DS) footfall patterns and
             higher peak vertical forces on the hindlimbs compared to the
             forelimbs. The walking gait of the woolly opossum (Caluromys
             philander), a highly arboreal marsupial, is also
             characterized by diagonal-sequence footfalls and relatively
             low peak forelimb forces. Among primates, three species-
             Callithrix, Nycticebus, and Loris -have been reported to
             frequently use lateral-sequence (LS) gaits and experience
             relatively higher peak vertical forces on the forelimbs.
             These patterns among primates and other mammals suggest a
             strong association between footfall patterns and force
             distribution on the limbs. However, current data for lorises
             are limited and the frequency of DS vs. LS walking gaits in
             Loris is still ambiguous. To test the hypothesis that
             patterns of footfalls and force distribution on the limbs
             are functionally linked, kinematic and kinetic data were
             collected simultaneously for three adult slender lorises
             (Loris tardigradus) walking on a 1.25 cm horizontal pole.
             All subjects in this study consistently used
             diagonal-sequence walking gaits and always had higher peak
             vertical forces on their forelimbs relative to their
             hindlimbs. These results call into question the hypothesis
             that a functional link exists between the presence of
             diagonal-sequence walking gaits and relatively higher peak
             vertical forces on the hindlimbs. In addition, this study
             tested models that explain patterns of force distribution
             based on limb protraction angle or limb compliance. None of
             the Loris subjects examined showed kinematic patterns that
             would support current models proposing that weight
             distribution can be adjusted by actively shifting weight
             posteriorly or by changing limb stiffness. These data reveal
             the complexity of adaptations to arboreal locomotion in
             primates and indicate that diagonal-sequence walking gaits
             and relatively low forelimb forces could have evolved
             independently. © 2004 Elsevier Ltd. All rights
             reserved.},
   Language = {eng},
   Doi = {10.1016/j.jhevol.2004.05.006},
   Key = {fds241103}
}

@article{fds241111,
   Author = {Lemelin, P and Schmitt, D},
   Title = {Seasonal variation in body mass and locomotor kinetics of
             the fat-tailed dwarf lemur (Cheirogaleus
             medius)},
   Journal = {Journal of Morphology},
   Volume = {260},
   Number = {1},
   Pages = {65-71},
   Year = {2004},
   url = {http://dx.doi.org/10.1002/jmor.10214},
   Abstract = {The fat-tailed dwarf lemur (Cheirogaleus medius) is unusual
             among primates in storing large amounts of fat
             subcutaneously prior to hibernating during the winter
             months. In doing so, it increases its body mass by more than
             50%, with a substantial weight gain in the tail. This
             seasonal increase in mass provides a unique natural
             experiment to examine how changes in body mass affect
             substrate reaction forces during locomotion. As body mass
             increases, it is expected that the limbs of the fat-tailed
             dwarf lemur will be subjected to greater peak vertical
             substrate reaction forces during quadrupedal walking.
             However, whether or not these peak substrate reaction forces
             will increase proportionally across forelimbs and hindlimbs
             as body mass increases is unknown. Substrate reaction forces
             were collected on four adult C. medius walking quadrupedally
             on a 28-mm pole attached to a force platform. Peak vertical
             substrate reaction forces (Vpk) (N) were analyzed and
             compared for a cross-sectional sample of different body
             masses (180-300 g). Forelimb and hindlimb Vpk were
             positively correlated with body mass, with hindlimb Vpk
             always higher than forelimb Vpk. However, the rate at which
             Vpk increased relative to body mass was higher for the
             hindlimb than the forelimb. This disproportion in weight
             distribution between the forelimbs and hindlimbs as body
             mass increases appears to be linked to the accumulation of
             fat in the tail. It is likely that storing fat in the tail
             region may shift the center of mass more caudally, from a
             more cranial position when the tail is thinner. Such a
             caudal shift of the center of mass - either morphological or
             dynamic - is believed to have played an important role in
             the functional differentiation of the limbs and the
             evolution of locomotor modes of several tetrapod groups,
             including dinosaurs and primates. © 2004 Wiley-Liss,
             Inc.},
   Doi = {10.1002/jmor.10214},
   Key = {fds241111}
}

@article{fds241120,
   Author = {Vinyard, CJ and Schmitt, D},
   Title = {New technique for studying reaction forces during primate
             behaviors on vertical substrates},
   Journal = {American Journal of Physical Anthropology},
   Volume = {125},
   Number = {4},
   Pages = {343-351},
   Year = {2004},
   url = {http://dx.doi.org/10.1002/ajpa.10395},
   Abstract = {Recording reaction forces from primates during behaviors on
             vertical substrates, such as leaping, climbing, or biting
             trees, typically requires the design and construction of
             customized recording devices or mounting commercially
             available force platforms in a vertical position. The
             technical difficulties imposed by either option have
             hindered in vivo research on the kinetics of primate
             behaviors on vertical substrates. We describe a simple,
             inexpensive apparatus for recording forces from primate
             behaviors on vertical substrates. The apparatus includes an
             instrumented beam fastened directly to a horizontal force
             platform and a surrounding vertical substrate that does not
             contact the instrumented beam or platform. The contact piece
             at the end of the instrumented beam is positioned flush with
             the noninstrumented vertical substrate, and reaction forces
             elicited on this instrumented section are directed to the
             force platform. Because most of the vertical substrate is
             not instrumented, we can isolate and record forces from a
             single limb or jaw during a behavior. Biewener and Full
             ([1992] Biomechanics Structures and Positions: A Practical
             Approach; New York: Oxford University press, p. 45-73) gave
             seven criteria to consider when designing a customized
             force-recording device. Where appropriate, we tested if our
             apparatus met their criteria. The apparatus accurately
             records forces in three orthogonal directions, has low
             cross-talk, maintains a high frequency response, exhibits a
             linear response up to at least 200 Newtons, and displays a
             uniform response to a given force across the instrumented
             contact piece. Our design does not easily facilitate the
             identification of the point of force application. Therefore,
             joint moments cannot be easily calculated. This limitation,
             however, does not affect the apparatus's ability to
             accurately record the magnitude and direction of a force (as
             shown by other tests). We developed this apparatus to
             measure jaw forces during tree gouging in common marmosets
             (Callithrix jacchus), but the general design can be readily
             modified to study a variety of primate behaviors on vertical
             substrates. © 2004 Wiley-Liss, Inc.},
   Doi = {10.1002/ajpa.10395},
   Key = {fds241120}
}

@article{fds241122,
   Author = {Schmitt, D and Lemelin, P},
   Title = {Locomotor mechanics of the slender loris.},
   Journal = {Journal of Human Evolution},
   Volume = {47},
   Pages = {85-94},
   Year = {2004},
   Key = {fds241122}
}

@article{fds241123,
   Author = {Schmitt, D and Hanna, J},
   Title = {Substrate alters forelimb to hindlimb peak force ratios on
             primates},
   Journal = {Journal of Human Evolution},
   Volume = {46},
   Pages = {237-252},
   Year = {2004},
   Key = {fds241123}
}

@article{fds241124,
   Author = {Lemelin, P and Schmitt, D},
   Title = {easonal variation in body mass and locomotor dynamics of the
             fat-tailed dwarf lemur (Cheirogaleus medius)},
   Journal = {Journal of Morphology},
   Volume = {260},
   Pages = {65-71},
   Year = {2004},
   Key = {fds241124}
}

@article{fds241118,
   Author = {Lemelin, P and Schmitt, D and Cartmill, M},
   Title = {Footfall patterns and interlimb co-ordination in opossums
             (Family Didelphidae): Evidence for the evolution of
             diagonal-sequence walking gaits in primates},
   Journal = {Journal of Zoology},
   Volume = {260},
   Number = {4},
   Pages = {423-429},
   Publisher = {WILEY},
   Year = {2003},
   Month = {August},
   url = {http://dx.doi.org/10.1017/S0952836903003856},
   Abstract = {Most primates typically use a diagonal-sequence footfall
             pattern during walking. This footfall pattern, which is
             unusual for mammals, is believed to have originated in
             ancestral primates in association with the use of grasping
             extremities for movement and foraging on thin, flexible
             branches. This theory was tested by comparing gait
             parameters between the grey short-tailed opossum Monodelphis
             domestica and the woolly opossum Caluromys philander, two
             didelphid marsupials that are strongly differentiated in
             grasping morphology of the extremities and in their reliance
             on foraging strategies involving thin branches. One hundred
             and thirty gait cycles were analysed quantitatively from
             videotapes of subjects moving quadrupedally on a runway and
             on poles of different diameters (7 and 28 mm). Duty factor
             (i.e. duration of the stance phase as a percentage of the
             stride period) for the forelimb and hindlimb, as well as
             diagonality (i.e. phase relationship between the forelimb
             and hindlimb cycles), were calculated for each of these
             symmetrical gait cycles. We found that the highly
             terrestrial Monodelphis, like most other non-primate
             mammals, relies primarily on lateral-sequence walking gaits
             on both runway and poles, and has relatively higher forelimb
             duty factors. Like primates, the highly arboreal Caluromys
             uses primarily diagonal-sequence walking gaits on the runway
             and pole, with relatively higher hindlimb duty factors and
             diagonality. The fact that the woolly opossum, a marsupial
             with primate-like feet that moves and forages mainly on thin
             branches, uses primarily diagonal-sequence gaits when
             walking supports the view that primate gaits evolved to meet
             the demands of locomotion on narrow supports. This also
             demonstrates the functional role of a grasping foot, in
             association with relatively higher hindlimb duty factors,
             protraction, and substrate reaction forces, in the
             production of such walking gaits.},
   Doi = {10.1017/S0952836903003856},
   Key = {fds241118}
}

@article{fds53030,
   Author = {D Schmitt},
   Title = {Insights into the evolution of human bipedalism from
             experimental studies of humans and other
             primates.},
   Journal = {The Journal of experimental biology},
   Volume = {206},
   Number = {Pt 9},
   Pages = {1437-48},
   Year = {2003},
   Month = {May},
   ISSN = {0022-0949},
   url = {http://dx.doi.org/10.1002/ajpa.10214},
   Keywords = {Adaptation, Biological • Animals • Biological
             Evolution* • Biomechanics • Gait • Humans
             • Locomotion • Models, Biological •
             physiology*},
   Abstract = {An understanding of the evolution of human bipedalism can
             provide valuable insights into the biomechanical and
             physiological characteristics of locomotion in modern
             humans. The walking gaits of humans, other bipeds and most
             quadrupedal mammals can best be described by using an
             inverted-pendulum model, in which there is minimal change in
             flexion of the limb joints during stance phase. As a result,
             it seems logical that the evolution of bipedalism in humans
             involved a simple transition from a relatively stiff-legged
             quadrupedalism in a terrestrial ancestor to relatively
             stiff-legged bipedalism in early humans. However,
             experimental studies of locomotion in humans and nonhuman
             primates have shown that the evolution of bipedalism
             involved a much more complex series of transitions,
             originating with a relatively compliant form of
             quadrupedalism. These studies show that relatively compliant
             walking gaits allow primates to achieve fast walking speeds
             using long strides, low stride frequencies, relatively low
             peak vertical forces, and relatively high impact shock
             attenuation ratios. A relatively compliant, ape-like bipedal
             walking style is consistent with the anatomy of early
             hominids and may have been an effective gait for a small
             biped with relatively small and less stabilized joints,
             which had not yet completely forsaken arboreal locomotion.
             Laboratory-based studies of primates also suggest that human
             bipedalism arose not from a terrestrial ancestor but rather
             from a climbing, arboreal forerunner. Experimental data, in
             conjunction with anatomical data on early human ancestors,
             show clearly that a relatively stiff modern human gait and
             associated physiological and anatomical adaptations are not
             primitive retentions from a primate ancestor, but are
             instead recently acquired characters of our
             genus.},
   Language = {eng},
   Doi = {10.1002/ajpa.10214},
   Key = {fds53030}
}

@article{fds304463,
   Author = {Schmitt, D and Churchill, SE and Hylander, WL},
   Title = {Experimental evidence concerning spear use in Neandertals
             and early modern humans},
   Journal = {Journal of Archaeological Science},
   Volume = {30},
   Number = {1},
   Pages = {103-114},
   Publisher = {Elsevier BV},
   Year = {2003},
   Month = {January},
   url = {http://dx.doi.org/10.1006/jasc.2001.0814},
   Abstract = {Can a bimanual activity such as thrusting a spear during
             hunting produce bilateral asymmetries in the strength of the
             upper limbs? This question is important to arguments about
             the predatory capabilities of Neandertals and early modern
             humans. To address this question, we determined the
             magnitude and direction of reaction forces on the upper
             limbs during thrusting spear use. We collected lateral video
             records of eight adults thrusting an instrumented aluminum
             rod into a padded target. This "spear" was instrumented with
             two sets of four strain gauges placed at two positions along
             the shaft to register the force along the shaft and the
             distribution of those forces relative to the two limbs. From
             the gauge output and video we were able to calculate loads
             experienced by the trailing limb (holding the proximal
             spear) and the leading limb (holding the distal spear) as
             well as approximate bending moments along the trailing limb.
             The trailing limb provides a significantly greater portion
             of the force during spear impact and when the spear is held
             forcefully on the target. The loads on this limb at spear
             impact are twice body weight and the bending moments on the
             trailing humerus are large and appear to occur primarily in
             the parasagittal plane. These data, in combination with
             fossil humeral cross-sectional data and the lack of evidence
             for throwing spears among Eurasian Neandertals, suggest that
             previously documented humeral strength asymmetries in
             Eurasian Neandertals and early Upper Palcolithic Modern
             human males can be plausibly linked to spear thrusting. ©
             2002 Elsevier Science Ltd. All rights reserved.},
   Doi = {10.1006/jasc.2001.0814},
   Key = {fds304463}
}

@article{fds44918,
   Author = {D. Schmitt},
   Title = {Evolutionary implications of the unusual walking mechanics
             of the common marmoset (Callithrix jacchus).},
   Journal = {American Journal of Physical Anthropology},
   Volume = {122},
   Pages = {28-37},
   Year = {2003},
   Key = {fds44918}
}

@article{fds241075,
   Author = {Schmitt, D},
   Title = {Mediolateral reaction forces and forelimb anatomy in
             quadrupedal primates: Implications for interpreting
             locomotor behavior in fossil primates},
   Journal = {Journal of Human Evolution},
   Volume = {44},
   Number = {1},
   Pages = {47-58},
   Year = {2003},
   ISSN = {0047-2484},
   url = {http://dx.doi.org/10.1016/S0047-2484(02)00165-3},
   Keywords = {Animals • Arm • Biomechanics • Elbow •
             Fossils* • Haplorhini • Locomotion • Motor
             Activity • Posture • anatomy & histology* •
             physiology • physiology*},
   Abstract = {The forelimb joints of terrestrial primate quadrupeds appear
             better able to resist mediolateral (ML) shear forces than
             those of arboreal quadrupedal monkeys. These differences in
             forelimb morphology have been used extensively to infer
             locomotor behavior in extinct primate quadrupeds. However,
             the nature of ML substrate reaction forces (SRF) during
             arboreal and terrestrial quadrupedalism in primates is not
             known. This study documents ML-SRF magnitude and orientation
             and forelimb joint angles in six quadrupedal anthropoid
             species walking across a force platform attached to
             terrestrial (wooden runway) and arboreal supports (raised
             horizontal poles). On the ground all subjects applied a
             lateral force in more than 50% of the steps collected. On
             horizontal poles, in contrast, all subjects applied a
             medially directed force to the substrate in more than 75% of
             the steps collected. In addition, all subjects on arboreal
             supports combined a lower magnitude peak ML-SRF with a
             change in the timing of the ML-SRF peak force. As a result,
             during quadrupedalism on the poles the overall SRF resultant
             was relatively lower than it was on the runway. Most
             subjects in this study adduct their humerus while on the
             poles. The kinetic and kinematic variables combine to
             minimize the tendency to collapse or translate forelimbs
             joints in an ML plane in primarily arboreal quadrupedal
             primates compared to primarily terrestrial quadrupedal ones.
             These data allow for a more complete understanding of the
             anatomy of the forelimb in terrestrial vs. arboreal
             quadrupedal primates. A better understanding of the
             mechanical basis of morphological differences allows greater
             confidence in inferences concerning the locomotion of
             extinct primate quadrupeds. © 2003 Elsevier Science Ltd.
             All rights reserved.},
   Language = {eng},
   Doi = {10.1016/S0047-2484(02)00165-3},
   Key = {fds241075}
}

@article{fds241076,
   Author = {Schmitt, D},
   Title = {Evolutionary implications of the unusual walking mechanics
             of the common marmoset (C. jacchus)},
   Journal = {American Journal of Physical Anthropology},
   Volume = {122},
   Number = {1},
   Pages = {28-37},
   Year = {2003},
   ISSN = {0002-9483},
   url = {http://dx.doi.org/10.1002/ajpa.10214},
   Keywords = {Animals • Biological Evolution* • Biomechanics
             • Callithrix • Gait • Male • Walking*
             • anatomy & histology* • physiology},
   Abstract = {Several features that appear to differentiate the walking
             gaits of most primates from those of most other mammals (the
             prevalence of diagonal-sequence footfalls, high degrees of
             humeral protraction, and low forelimb vs. hindlimb peak
             vertical forces) are believed to have evolved in response to
             requirements of locomotion on thin arboreal supports by
             early primates that had developed clawless grasping hands
             and feet. This putative relationship between anatomy,
             behavior, and ecology is tested here by examining gait
             mechanics in the common marmoset (Callithrix jacchus), a
             primate that has sharp claws and reduced pedal grasping, and
             that spends much of its time clinging on large trunks.
             Kinematic and kinetic data were collected on three male
             Callithrix jacchus as they walked across a force platform
             attached to the ground or to raised horizontal poles. The
             vast majority of all walking gaits were lateral-sequence.
             For all steps, the humerus was retracted (&lt;90° relative
             to a horizontal axis) or held in a neutral (90°) position
             at forelimb touchdown. Peak vertical forces on the forelimb
             were always higher than those on the hindlimb. These three
             features of the walking gaits of C. jacchus separate it from
             any other primate studied (including other callitrichids).
             The walking gaits of C. jacchus are mechanically more
             similar to those of small, nonprimate mammals. The results
             of this study support previous models that suggest that the
             unusual suite of features that typify the walking gaits of
             most primates are adaptations to the requirements of
             locomotion on thin arboreal supports. These data, along with
             data from other primates and marsupials, suggest that
             primate postcranial and locomotor characteristics are part
             of a basal adaptation for walking on thin branches. © 2003
             Wiley-Liss, Inc.},
   Language = {eng},
   Doi = {10.1002/ajpa.10214},
   Key = {fds241076}
}

@article{fds241117,
   Author = {Schmitt, D},
   Title = {Substrate Size Primate Forelimb Mechanics: Implications for
             Understanding the Evolution of Primate Locomotion},
   Journal = {International Journal of Primatology},
   Volume = {24},
   Number = {5},
   Pages = {1023-1036},
   Year = {2003},
   ISSN = {0164-0291},
   url = {http://dx.doi.org/10.1023/A:1026224211797},
   Abstract = {Did the anatomical and locomotor specializations of primates
             evolve in response to requirements of locomotion and
             foraging on thin branches? Laboratory studies of primates
             and other mammals provide data suggesting that as substrate
             size decreases primates will protract their arms to a
             greater degree, lower the center of gravity by increasing
             elbow flexion, and decrease forelimb substrate reaction
             forces. I tested these hypotheses by calculating maximum arm
             protraction, shoulder height, elbow flexion, and substrate
             reaction forces during stance phase in 5 species of Old
             World monkeys walking on a flat runway and raised poles of
             varying diameters. As substrate size decreased most subjects
             increased elbow flexion and lowered their shoulder height.
             Three of the 5 species lowered peak substrate reaction
             forces as substrate size decreased but, only 2 of the
             species increased arm protraction as substrate size
             decreased. These results reject the hypothesis that arm
             protraction is a function of branch size, but provide
             stronger support for the notion that branch size influences
             elbow flexion, shoulder height, and peak substrate reaction
             forces in some primates. The fact that biomechanical
             expectations are met in some (but not all) cases and some
             (but not all) species suggests that the topic is quite
             complex and requires further study. Nonetheless, preliminary
             data suggest that biomechanical accommodations to substrate
             size may have played a role in the early differentiation of
             primates from other mammals.},
   Doi = {10.1023/A:1026224211797},
   Key = {fds241117}
}

@article{fds241119,
   Author = {Schmitt, D},
   Title = {Insights into the evolution of human bipedalism from
             experimental studies of humans and other
             primates},
   Journal = {Journal of Experimental Biology},
   Volume = {206},
   Number = {9},
   Pages = {1437-1448},
   Year = {2003},
   url = {http://dx.doi.org/10.1242/jeb.00279},
   Abstract = {An understanding of the evolution of human bipedalism can
             provide valuable insights into the biomechanical and
             physiological characteristics of locomotion in modern
             humans. The walking gaits of humans, other bipeds and most
             quadrupedal mammals can best be described by using an
             inverted-pendulum model, in which there is minimal change in
             flexion of the limb joints during stance phase. As a result,
             it seems logical that the evolution of bipedalism in humans
             involved a simple transition from a relatively stiff-legged
             quadrupedalism in a terrestrial ancestor to relatively
             stiff-legged bipedalism in early humans. However,
             experimental studies of locomotion in humans and nonhuman
             primates have shown that the evolution of bipedalism
             involved a much more complex series of transitions,
             originating with a relatively compliant form of
             quadrupedalism. These studies show that relatively compliant
             walking gaits allow primates to achieve fast walking speeds
             using long strides, low stride frequencies, relatively low
             peak vertical forces, and relatively high impact shock
             attenuation ratios. A relatively compliant, ape-like bipedal
             walking style is consistent with the anatomy of early
             hominids and may have been an effective gait for a small
             biped with relatively small and less stabilized joints,
             which had not yet completely forsaken arboreal locomotion.
             Laboratory-based studies of primates also suggest that human
             bipedalism arose not from a terrestrial ancestor but rather
             from a climbing, arboreal forerunner. Experimental data, in
             conjunction with anatomical data on early human ancestors,
             show clearly that a relatively stiff modern human gait and
             associated physiological and anatomical adaptations are not
             primitive retentions from a primate ancestor, but are
             instead recently acquired characters of our
             genus.},
   Doi = {10.1242/jeb.00279},
   Key = {fds241119}
}

@article{fds241114,
   Author = {Cartmill, M and Lemelin, P and Schmitt, D},
   Title = {Support polygons and symmetrical gaits in
             mammals},
   Journal = {Zoological Journal of the Linnean Society},
   Volume = {136},
   Number = {3},
   Pages = {401-420},
   Publisher = {Oxford University Press (OUP)},
   Year = {2002},
   Month = {November},
   url = {http://dx.doi.org/10.1046/j.1096-3642.2002.00038.x},
   Abstract = {The symmetrical gaits of quadrupedal mammals are often
             described in terms of two variables: duty factor (S = the
             stance period of one foot, as a percentage of the gait
             cycle) and diagonality (D = the percentage of the cycle
             period by which the left hind footfall precedes the left
             fore footfall). We show that support polygons are optimized
             during walking (i.e. the percentage of the locomotor cycle
             spent standing on only two feet is minimized) for: (1) the
             diagonal-sequence, diagonal-couplets walks characteristic of
             primates (50 < D < 75) when D = [hindlimb S]; (2)
             lateral-sequence, lateral-couplets walks (0 < D < 25) when D
             = [hindlimb S] - 50; (3) lateral-sequence, diagonal-couplets
             walks (25 < D < 50) when D = 100 - [forelimb S]. To
             determine whether animal behaviour is optimal in this sense,
             we examined 346 symmetrical gait cycles in 45 mammal
             species. Our empirical data show that mammalian locomotor
             behaviour approximates the theoretical optima. We suggest
             that diagonal-sequence walking may be adopted by primates as
             a means of ensuring that a grasping hindfoot is placed in a
             protracted position on a tested support at the moment when
             the contralateral forefoot strikes down on an untested
             support. © 2002 The Linnean Society of London.},
   Doi = {10.1046/j.1096-3642.2002.00038.x},
   Key = {fds241114}
}

@article{fds53033,
   Author = {E Krakauer and P Lemelin and D Schmitt},
   Title = {Hand and body position during locomotor behavior in the
             aye-aye (Daubentonia madagascariensis).},
   Journal = {American journal of primatology},
   Volume = {57},
   Number = {3},
   Pages = {105-18},
   Year = {2002},
   Month = {July},
   ISSN = {0275-2565},
   url = {http://dx.doi.org/10.1002/ajp.10038},
   Keywords = {Animals • Biomechanics • Female • Hand •
             Hand Injuries • Locomotion* • Male • Posture
             • Strepsirhini* • Stress, Mechanical • Trees
             • physiology* • veterinary},
   Abstract = {Aye-ayes (Daubentonia madagascariensis) have unique hands
             among primates, with extraordinarily long fingers in
             relation to body size. These long digits may be vulnerable
             to damage from forces during locomotion, particularly during
             head-first descent-a locomotor mode that the aye-aye
             utilizes frequently. Previous behavioral studies of aye-aye
             locomotion reported that Daubentonia must curl its fingers
             during horizontal quadrupedalism and/or descent to reduce
             potential stresses on its long fingers. To test this
             hypothesis, we examined hand and body position in three
             captive adult aye-ayes while they walked quadrupedally on
             horizontal and oblique branches. Substantial variation in
             hand position was observed among individuals for each
             substrate orientation. While hand postures with curled
             fingers were preferred by one individual during descent,
             they were not preferred by the other two individuals,
             contrary to our expectations. Differences in body position
             were more consistent among all three individuals. The angle
             of the body relative to the substrate was significantly
             reduced during descent (8.4 degrees ) compared to horizontal
             locomotion (16.9 degrees ). These results suggest that
             changes in body position, rather than hand position, may
             help reduce stresses on the digits. A biomechanical model is
             proposed that demonstrates how a reduction in the body angle
             in relation to substrate may act to move the center of mass
             more caudally. This mechanism of moderating loads by
             altering body position, rather than hand position, may
             represent an important functional aspect of arboreal
             locomotion in aye-ayes and other primates.},
   Language = {eng},
   Doi = {10.1002/ajp.10038},
   Key = {fds53033}
}

@article{fds241102,
   Author = {Schmitt, D and Lemelin, P},
   Title = {Origins of primate locomotion: Gait mechanics of the woolly
             opossum},
   Journal = {American Journal of Physical Anthropology},
   Volume = {118},
   Number = {3},
   Pages = {231-238},
   Year = {2002},
   ISSN = {0002-9483},
   url = {http://dx.doi.org/10.1002/ajpa.10048},
   Keywords = {Animals • Anthropology, Physical • Biomechanics
             • Gait* • Locomotion* • Opossums •
             Primates • Species Specificity • anatomy &
             histology • physiology*},
   Abstract = {The locomotion ot primates differs from that of other
             mammals in three fundamental ways. During quadrupedal
             walking, primates use diagonal sequence gaits, protract
             their arms more at forelimb touchdown, and experience lower
             vertical substrate reaction forces on their forelimbs
             relative to their hindlimbs. It is widely held that the
             unusual walking gaits of primates represent a basal
             adaptation for movement on thin, flexible branches and
             reflect a major change in the functional role of the
             forelimb. However, little data on nonprimate arboreal
             mammals exist to test this notion. To that end, we examined
             the gait mechanics of the woolly opossum (Caluromys
             philander), a marsupial convergent with small-bodied
             prosimians in ecology, behavior, and morphology. Data on the
             footfall sequence, relative arm protraction, and peak
             vertical substrate reaction forces were obtained from
             videotapes and force records for three adult woolly opossums
             walking quadrupedally on a wooden runway and a thin pole.
             For all steps recorded on both substrates, woolly opossums
             always used diagonal sequence walking gaits, protracted
             their arms beyond 90° relative to horizontal body axis, and
             experienced peak vertical substrate reaction forces on
             forelimbs that were significantly lower than on hindlimbs.
             The woolly opossum is the first non-primate mammal to show
             locomotor mechanics that are identical to those of primates.
             This case of convergence between primates and a committed
             fine-branch, arboreal marsupial strongly implies that the
             earliest primates evolved gait specializations for
             fine-branch locomotion, which reflect important changes in
             forelimb function. Am J Phys Anthropol 118:231-238, 2002. ©
             2002 Wiley-Liss, Inc.},
   Language = {eng},
   Doi = {10.1002/ajpa.10048},
   Key = {fds241102}
}

@article{fds241115,
   Author = {Krakauer, E and Lemelin, P and Schmitt, D},
   Title = {Hand and body position during locomotor behavior in the
             aye-aye (Daubentonia madagascariensis)},
   Journal = {American Journal of Primatology},
   Volume = {57},
   Number = {3},
   Pages = {105-118},
   Year = {2002},
   ISSN = {0275-2565},
   url = {http://dx.doi.org/10.1002/ajp.10038},
   Abstract = {Aye-ayes (Daubentonia madagascariensis) have unique hands
             among primates, with extraordinarily long fingers in
             relation to body size. These long digits may be vulnerable
             to damage from forces during locomotion, particularly during
             head-first descent - a locomotor mode that the aye-aye
             utilizes frequently. Previous behavioral studies of aye-aye
             locomotion reported that Daubentonia must curl its fingers
             during horizontal quadrupedalism and/or descent to reduce
             potential stresses on its long fingers. To test this
             hypothesis, we examined hand and body position in three
             captive adult aye-ayes while they walked quadrupedally on
             horizontal and oblique branches. Substantial variation in
             hand position was observed among individuals for each
             substrate orientation. While hand postures with curled
             fingers were preferred by one individual during descent,
             they were not preferred by the other two individuals,
             contrary to our expectations. Differences in body position
             were more consistent among all three individuals. The angle
             of the body relative to the substrate was significantly
             reduced during descent (8.4°) compared to horizontal
             locomotion (16.9°). These results suggest that changes in
             body position, rather than hand position, may help reduce
             stresses on the digits. A biomechanical model is proposed
             that demonstrates how a reduction in the body angle in
             relation to substrate may act to move the center of mass
             more caudally. This mechanism of moderating loads by
             altering body position, rather than hand position, may
             represent an important functional aspect of arboreal
             locomotion in aye-ayes and other primates. © 2002
             Wiley-Liss, Inc.},
   Doi = {10.1002/ajp.10038},
   Key = {fds241115}
}

@article{fds241116,
   Author = {Schmitt, D and Churchill, SE and Hylander, WL},
   Title = {Experimental evidence concerning spear use in Neandertals
             and early modern humans.},
   Journal = {Journal of Archaeological Sciences},
   Volume = {30},
   Number = {1},
   Pages = {101-112},
   Year = {2002},
   url = {http://dx.doi.org/10.1006/jasc.2001.0814},
   Abstract = {Can a bimanual activity such as thrusting a spear during
             hunting produce bilateral asymmetries in the strength of the
             upper limbs? This question is important to arguments about
             the predatory capabilities of Neandertals and early modern
             humans. To address this question, we determined the
             magnitude and direction of reaction forces on the upper
             limbs during thrusting spear use. We collected lateral video
             records of eight adults thrusting an instrumented aluminum
             rod into a padded target. This "spear" was instrumented with
             two sets of four strain gauges placed at two positions along
             the shaft to register the force along the shaft and the
             distribution of those forces relative to the two limbs. From
             the gauge output and video we were able to calculate loads
             experienced by the trailing limb (holding the proximal
             spear) and the leading limb (holding the distal spear) as
             well as approximate bending moments along the trailing limb.
             The trailing limb provides a significantly greater portion
             of the force during spear impact and when the spear is held
             forcefully on the target. The loads on this limb at spear
             impact are twice body weight and the bending moments on the
             trailing humerus are large and appear to occur primarily in
             the parasagittal plane. These data, in combination with
             fossil humeral cross-sectional data and the lack of evidence
             for throwing spears among Eurasian Neandertals, suggest that
             previously documented humeral strength asymmetries in
             Eurasian Neandertals and early Upper Palcolithic Modern
             human males can be plausibly linked to spear thrusting. ©
             2002 Elsevier Science Ltd. All rights reserved.},
   Doi = {10.1006/jasc.2001.0814},
   Key = {fds241116}
}

@article{fds241113,
   Author = {Larson, SG and Schmitt, D and Lemelin, P and Hamrick,
             M},
   Title = {Limb excursion during quadrupedal walking: How do primates
             compare to other mammals?},
   Journal = {Journal of Zoology},
   Volume = {255},
   Number = {3},
   Pages = {353-365},
   Publisher = {WILEY},
   Year = {2001},
   Month = {November},
   ISSN = {0952-8369},
   url = {http://dx.doi.org/10.1017/S0952836901001455},
   Abstract = {Primate quadrupeds are said to use relatively large limb
             excursions for mammals of their body size. Until recently,
             this claim was based on a comparison of hindlimb excursion
             data derived from small samples of primates and
             non-primates. Using video recordings collected at zoos and
             primate research centres, the present study documents this
             contrast on much wider samples of quadrupedal mammals. The
             results indicate that while on average hindlimb excursion is
             relatively larger in quadrupedal primates, this contrast is
             somewhat less dramatic than first reports suggested.
             Comparisons between the data reported here and previously
             collected forelimb excursion data reveal a surprising
             asymmetry between the fore- and hind excursions for most
             mammalian species. Most commonly, forelimb excursion exceeds
             that of the hindlimb. We suggest that this is related to a
             complementary asymmetry in limb length (forelimbs shorter
             than hind) for the purpose of achieving equal step lengths
             for both pairs of limbs. Relatively large hindlimb
             excursions in primates have been related to a mechanism that
             reduces stresses on the forelimbs and then recovers
             mechanical energy during gait. We suggest that large
             excursions of both the fore- and hindlimbs are linked to
             other alterations in gait parameters, such as step length,
             contact time, and limb compliance, that have been adopted in
             quadrupedal primates to facilitate locomotion along slender
             arboreal substrates.},
   Doi = {10.1017/S0952836901001455},
   Key = {fds241113}
}

@article{fds241112,
   Author = {Larson, SG and Schmitt, D and Lemelin, P and Hamrick,
             M},
   Title = {Uniqueness of primate forelimb posture during quadrupedal
             locomotion},
   Journal = {American Journal of Physical Anthropology},
   Volume = {112},
   Number = {1},
   Pages = {87-101},
   Publisher = {WILEY},
   Year = {2000},
   Month = {May},
   url = {http://dx.doi.org/10.1002/(sici)1096-8644(200005)112:1<87::aid-ajpa9>3.0.co;2-},
   Abstract = {Among the characteristics that are thought to set primate
             quadrupedal locomotion apart from that of nonprimate mammals
             are a more protracted limb posture and larger limb angular
             excursion. However, kinematic aspects of primate or
             nonprimate quadrupedal locomotion have been documented in
             only a handful of species, and more widely for the hind than
             the forelimb. This study presents data on arm (humerus) and
             forelimb posture during walking for 102 species of mammals,
             including 53 nonhuman primates and 49 nonprimate mammals.
             The results demonstrate that primates uniformly display a
             more protracted arm and forelimb at hand touchdown of a step
             than nearly all other mammals. Although primates tend to end
             a step with a less retracted humerus, their total humeral or
             forelimb angular excursion exceeds that of other mammals. It
             is suggested that these features are components of
             functional adaptations to locomotion in an arboreal habitat,
             using clawless, grasping extremities.},
   Doi = {10.1002/(sici)1096-8644(200005)112:1<87::aid-ajpa9>3.0.co;2-},
   Key = {fds241112}
}

@article{fds241074,
   Author = {Schmitt, D},
   Title = {Compliant walking in primates},
   Journal = {Journal of Zoology},
   Volume = {248},
   Number = {2},
   Pages = {149-160},
   Publisher = {WILEY},
   Year = {1999},
   Month = {June},
   url = {http://dx.doi.org/10.1017/S0952836999006020},
   Abstract = {It is now well recognized that terrestrial mammals can
             maintain equivalent bone stresses despite dramatic
             differences in body size through the adoption of extended
             limb positions during locomotion. However, this dynamic
             solution is not available to all mammals. Medium- and
             large-bodied arboreal mammals, such as anthropoid primates,
             must maintain relatively gracile and mobile limbs in order
             to manoeuvre in a discontinuous arboreal environment. But
             they must also use flexed (i.e. crouched) limb positions in
             order to maintain balance on arboreal substrates, thus
             subjecting their gracile limbs to relatively high loads. To
             determine how primates resolve this conflict between their
             kinematics and their morphology, five species of Old World
             monkeys were videotaped with lateral, frontal, and overhead
             cameras while they walked at a range of natural speeds along
             a runway and raised horizontal poles instrumented with a
             force platform. Kinematic and kinetic data on the forelimb
             show that during arboreal quadrupedalism, Old World monkeys
             do crouch when travelling on arboreal supports compared to
             the ground. Simultaneously, they lower vertical peak
             reaction forces and thereby reduce and reorient the peak
             resultant substrate reaction force, so that moment arms and
             moments are roughly equivalent on poles and the ground. This
             is accomplished through the adoption of a compliant walking
             gait characterized by high degrees of forelimb protraction,
             substantial elbow yield, low vertical oscillations of the
             body, and long contact times. The use of a compliant walking
             gait appears to be extremely rare among mammals and is most
             likely related to an initial primate adaptation to
             quadrupedal locomotion on terminal branches. This gait
             represents a previously unrecognized dynamic postural
             mechanism for maintenance of similar bone stresses and
             safety factors in both arboreal and terrestrial
             environments.},
   Doi = {10.1017/S0952836999006020},
   Key = {fds241074}
}

@article{fds241110,
   Author = {Turnquist, JE and Schmitt, D and Rose, MD and Cant,
             JG},
   Title = {Pendular motion in the brachiation of captive Lagothrix and
             Ateles.},
   Journal = {American Journal of Primatology},
   Volume = {48},
   Number = {4},
   Pages = {263-281},
   Year = {1999},
   Month = {January},
   ISSN = {0275-2565},
   url = {http://dx.doi.org/10.1002/(sici)1098-2345(1999)48:4<263::aid-ajp2>3.0.co},
   Abstract = {Pendular motion during brachiation of captive Lagothrix
             lagothricha lugens and Ateles fusciceps robustus was
             analyzed to demonstrate similarities, and differences,
             between these two closely related large bodied atelines.
             This is the first captive study of the kinematics of
             brachiation in Lagothrix. Videorecordings of one adult male
             of each species were made in a specially designed cage
             constructed at the DuMond Conservancy/Monkey Jungle, Miami,
             FL. Java software (Jandel Scientific Inc., San Rafael, CA)
             was used for frame-by-frame kinematic analysis of individual
             strides/steps. Results demonstrate that the sequence of hand
             and tail contacts differ significantly between the two
             species with Lagothrix using a new tail hold with every hand
             hold, while Ateles generally utilizes a new tail hold with
             only every other hand hold. Stride length and stride
             frequency, even after adjusting for limb length, also differ
             significantly between the two species. Lagothrix brachiation
             utilizes short, choppy strides with quick hand holds, while
             Ateles uses long, fluid strides with longer hand holds.
             During brachiation not only is Lagothrix's body
             significantly less horizontal than that of Ateles but also,
             within Ateles, there are significant differences between
             steps depending on tail use. Because of the unique nature of
             tail use in Ateles, many aspects of body positioning in
             Lagothrix more closely resemble Ateles steps without a
             simultaneous tail hold rather than those with one. Overall
             pendulum length in Lagothrix is shorter than in Ateles. Tail
             use in Ateles has a significant effect on maximum pendulum
             length during a step. Although neither species achieves the
             extreme pendulum effect and long period of free-flight of
             hylobatids in fast ricochetal brachiation, in captivity both
             consistently demonstrate effective brachiation with brief
             periods of free-flight and pendular motion. Morphological
             similarities between ateline brachiators and hylobatids are
             fewer and less pronounced in Lagothrix than in Ateles. This
             study demonstrates that Lagothrix brachiation is also less
             hylobatid-like than that of Ateles.},
   Doi = {10.1002/(sici)1098-2345(1999)48:4<263::aid-ajp2>3.0.co},
   Key = {fds241110}
}

@article{fds241083,
   Author = {Hamrick, MW and Churchill, SE and Schmitt, D and Hylander,
             WL},
   Title = {EMG of the human flexor pollicis longus muscle: implications
             for the evolution of hominid tool use.},
   Journal = {Journal of Human Evolution},
   Volume = {34},
   Number = {2},
   Pages = {123-136},
   Year = {1998},
   Month = {February},
   ISSN = {0047-2484},
   url = {http://www.ncbi.nlm.nih.gov/pubmed/9503091},
   Abstract = {Modern humans possess a distinct and well-developed flexor
             pollicis longus muscle, an extrinsic thumb flexor which is
             "either rudimentary or absent" in great apes (Straus, 1942,
             p. 228). Previous workers (e.g., Napier, 1962; Susman, 1988)
             have related the origin of a well-developed flexor pollicis
             longus muscle to the acquisition of precision grasping and
             stone tool making capabilities in early hominids. The
             proposed functional association between flexor pollicis
             longus activity, precision grasping, and stone tool
             manufacture has, however, never been tested experimentally.
             This study uses electromyographic techniques (EMG) to
             investigate the role of flexor pollicis longus during a
             variety of tool making, tool using, and manipulatory
             behaviors in order to determine the functional and
             evolutionary significance of the human flexor pollicis
             longus muscle. Our results indicate that flexor pollicis
             longus is recruited during forceful tool using and stone
             tool making behaviors, regardless of the power or precision
             grip used to hold the tool. In particular, both stone tool
             use and stone tool making employing three- and four-jaw
             chuck precision grips elicit consistently high levels of FPL
             activity. Flexor pollicis longus activity increases most
             when resistance is increased to the thumb's volar pad during
             these hammering, cutting, and knapping behaviors. In
             contrast, we observed relatively low levels of flexor
             pollicis longus activity during the fine manipulation of
             food items, the making of slender wooden probes, and the use
             of these probes as tools. The paleontological,
             archaeological, and experimental data suggest that a
             well-developed flexor pollicis longus muscle functioned
             initially in the hominid lineage to stabilize the terminal
             pollical phalanx against loads applied to the thumb's apical
             pad during the frequent and forceful use of unmodified
             stones as tools.},
   Doi = {10.1006/jhev.1997.0177},
   Key = {fds241083}
}

@article{fds241073,
   Author = {Lemelin, P and Schmitt, D},
   Title = {The relation between hand morphology and quadrupedalism in
             primates},
   Journal = {American Journal of Physical Anthropology},
   Volume = {105},
   Number = {2},
   Pages = {185-197},
   Year = {1998},
   ISSN = {0002-9483},
   url = {http://dx.doi.org/10.1002/(SICI)1096-8644(199802)105:2<185::AID-AJPA6>3.0.CO;2},
   Abstract = {Primate hands can be classified into two broad categories on
             the basis of ray proportions and other features. Ectaxonic
             hands are characterized by a longer fourth ray and are found
             in most strepsirhines. Most haplorhines possess mesaxonic
             hands which are characterized by a longer third ray.
             Preuschoft et al. ([1993] in H. Preuschoft and D.J. Chivers
             (eds.): Hands of Primates. Berlin: Springer-Verlag, pp.
             21-30) proposed a biomechanical model which predicts that,
             during quadrupedalism, a mesaxonic hand should be held in a
             more neutral position with respect to the forearm, whereas
             an ectaxonic hand should be more ulnarly deviated. The
             relation between hand positioning and the mesaxony/ectaxony
             categorization is investigated for 27 primate taxa.
             Videotapes were recorded for each species walking
             quadrupedally on arboreal supports. Several species were
             also videotaped during ground quadrupedalism. The degree of
             deviation of the hand relative to the substrate and the
             grips utilized were quantified for 18 species from the
             videotapes. Primates with mesaxonic hands use deviated hand
             positions and grips, especially when walking quadrupedally
             on small poles. Several species with ectaxonic hands use
             neutral hand positions and grips when walking quadrupedally
             on similar supports. Also, several primates, with either
             ectaxonic or mesaxonic hands, display a combination of
             deviated hand positions and grips when on arboreal
             substrates and neutral hand positioning when on the ground.
             The statistical results indicate that hand positioning
             during quadrupedal walking is more variable than expected
             based on the mesaxony/ectaxony classification. Furthermore,
             radiographic data suggest that primates evolved at least two
             different mechanisms of hand ulnar deviation.},
   Doi = {10.1002/(SICI)1096-8644(199802)105:2<185::AID-AJPA6>3.0.CO;2},
   Key = {fds241073}
}

@article{fds241072,
   Author = {Schmitt, D},
   Title = {Humeral Head Shape as an Indicator of Locomotor Behavior in
             Extant Strepsirhines and Eocene Adapids},
   Journal = {Folia Primatologica},
   Volume = {67},
   Number = {3},
   Pages = {137-151},
   Publisher = {S. Karger AG},
   Year = {1997},
   Month = {January},
   ISSN = {0015-5713},
   url = {http://dx.doi.org/10.1159/000157215},
   Keywords = {Analysis of Variance • Animals • Fossils* •
             Humerus • Locomotion* • Multivariate Analysis
             • Phylogeny* • Primates • Species Specificity
             • Strepsirhini • anatomy & histology •
             anatomy & histology* • classification •
             physiology*},
   Abstract = {Postcranial material from Notharctus, Smilodectes and
             Cantius is abundant and well studied, but debate continues
             over whether the locomotor repertoire of these animals
             included a substantial component of vertical leaping. Here,
             the shape of the humeral head of 11 genera of extant
             strepsirhines, Notharctus, Smilodectes and Cantius was
             quantified using serial mediolateral and proximodistal
             contours. Univariate and multivariate analyses of these data
             show that vertically leaping strepsirhines have a distally
             relatively high narrow humeral head compared to arboreal
             quadrupeds and it places Notharctus and Smilodectes in a
             group with Hapalemur griseus, while Cantius is grouped with
             Eulemur macaco, suggesting that a quadrupedal form preceded
             the appearance of vertical leaping.},
   Language = {eng},
   Doi = {10.1159/000157215},
   Key = {fds241072}
}

@article{fds318215,
   Author = {Schmitt, D},
   Title = {Humeral head shape as an indicator of locomotor behavior in
             extant strepsirhines and Eocene adapids.},
   Journal = {Folia Primatologica},
   Volume = {67},
   Number = {3},
   Pages = {137-151},
   Year = {1996},
   Abstract = {Postcranial material from Notharctus, Smilodectes and
             Cantius is abundant and well studied, but debate continues
             over whether the locomotor repertoire of these animals
             included a substantial component of vertical leaping. Here,
             the shape of the humeral head of 11 genera of extant
             strepsirhines, Notharctus, Smilodectes and Cantius was
             quantified using serial mediolateral and proximodistal
             contours. Univariate and multivariate analyses of these data
             show that vertically leaping strepsirhines have a distally
             relatively high narrow humeral head compared to arboreal
             quadrupeds and it places Notharctus and Smilodectes in a
             group with Hapalemur griseus, while Cantius is grouped with
             Eulemur macaco, suggesting that a quadrupedal form preceded
             the appearance of vertical leaping.},
   Key = {fds318215}
}

@article{fds241070,
   Author = {Schmitt, D and Larson, SG},
   Title = {Heel contact as a function of substrate type and speed in
             primates},
   Journal = {American Journal of Physical Anthropology},
   Volume = {96},
   Number = {1},
   Pages = {39-50},
   Year = {1995},
   ISSN = {0002-9483},
   url = {http://dx.doi.org/10.1002/ajpa.1330960105},
   Abstract = {In this report we provide detailed data on the patterns and
             frequency of heel contact with terrestrial and arboreal
             supports in primates. These data can help resolve the
             question of whether African apes and humans are uniquely
             'plantigrade' (Gebo [1992] Am. J. Phys. Anthropol. 89:29-58;
             Gebo [1993a] Am. J. Phys. Anthropol. 91:38-385; Gebo [1993b]
             Postcranial Adaptation in Nonhuman Primates), or if
             plantigrady is common in other primates (Meldrum [1993] Am.
             J. Phys. Anthropol. 91:379-381). Using biplanar and
             uniplanar videotapes, we recorded the frequency and timing
             of heel contact for a variety of primates (32 species)
             walking on the ground and on simulated arboreal supports at
             a range of natural speeds. Our results indicate that Pongo
             as well as the African apes exhibit a 'heel-strike' at the
             end of swing phase. Ateles and Hylobates make heel contact
             on all supports shortly after mid-foot contact, although
             spider monkeys do so only at slow or moderate speeds. Data
             available from uniplanar videotapes suggest that this
             pattern occurs in Alouatta and Lagothrix as well. No other
             New or Old World monkey or prosimian in this study made heel
             contact during quadrupedalism on any substrate. Thus, heel
             contact occurs in all apes and atelines, but only the great
             apes exhibit a heel-strike. We suggest that heel contact
             with the substrate is a by-product of an active posterior
             weight-shift mechanism involving highly protracted hindlimbs
             at touchdown. Force plate studies indicate that this
             mechanism is most extreme in arboreally adapted primate
             quadrupeds walking on arboreal supports. Although heel
             contact and heel- strike may have no evolutionary link, it
             is possible that both patterns are the result of a similar
             weight shift mechanism. Therefore, the regular occurrence of
             heel contact in a variety of arboreal primates, and the
             absence of a true biomechanical link between limb
             elongation, heel contact, and terrestriality, calls into
             question the claim that hominid foot posture was necessarily
             derived from a quadrupedal terrestrial ancestor.},
   Doi = {10.1002/ajpa.1330960105},
   Key = {fds241070}
}

@article{fds330391,
   Author = {Demes, B and Larson, SG and Stern, JT and Jungers, WL and Biknevicius,
             AR and Schmitt, D},
   Title = {The kinetics of primate quadrupedalism: "hindlimb drive"
             reconsidered},
   Journal = {Journal of Human Evolution},
   Volume = {26},
   Number = {5-6},
   Pages = {353-374},
   Publisher = {Elsevier BV},
   Year = {1994},
   Month = {May},
   url = {http://dx.doi.org/10.1006/jhev.1994.1023},
   Abstract = {Since Kimura et al.'s (1979) analysis of ground reaction
             forces during quadrupedal walking, primates are commonly
             pictured as being "hindlimb driven" compared to "forelimb
             driven" nonprimate mammals. Hindlimb dominance in primates
             has subsequently been interpreted as a preadaptation to
             human bipedalism. However, given its considerable influence,
             surprisingly little data are available to support this
             putative contrast in limb dominance. In this reconsideration
             of locomotor kinetics in primates, we have collected force
             plate data on two chimpanzees, one orangutan, two vervet
             monkeys, and two cats for a range of gaits and speeds. The
             peak vertical forces acting on the limbs as well as the
             braking and propulsive impulses exerted by the limbs are
             examined. Forces and impulses are highly variable and change
             with speed, gait, and the differential use of asynchronously
             or asymmetrically placed limbs. Peak vertical forces
             increase with speed. The faster gaits (trot, gallop) have,
             on the average, higher forces than the walk. However, there
             is no major change in force magnitudes at gait transitions.
             The mean vertical forces are higher on the hindlimbs than on
             the forelimbs of the primates. This difference is most
             pronounced in the suspensory orangutan and least pronounced
             in the quadrupedal vervets. Cats, on the other hand,
             generate higher forelimb than hindlimb vertical forces.
             Although our results support the overall conclusion of
             Kimura et al. (1979) that peak vertical forces are
             relatively low on the primate forelimb, they also show some
             variation most probably related to locomotor mode. In the
             majority of primate cases, the major propulsive thrust is
             also generated by the hindlimbs. However, in the galloping
             vervets, the trailing limbs are propulsive and the leading
             limbs braking, no matter whether these are forelimbs or
             hindlimbs. A similar, although less pronounced, asymmetry
             between trailing and leading limbs was observed in a
             galloping chimpanzee. Not only are primates variable with
             regard to the roles of the limbs in propulsion, they are
             also not unique among mammals in being predominantly
             hindlimb driven. Our cats, as well as all other nonprimate
             mammals so far analysed, generate greater propulsive thrust
             with their hindlimbs; i.e. they are also "hindlimb driven".
             © 1994 Academic Press. All rights reserved.},
   Doi = {10.1006/jhev.1994.1023},
   Key = {fds330391}
}

@article{fds241069,
   Author = {Schmitt, D},
   Title = {Forelimb mechanics as a function of substrate type during
             quadrupedalism in two anthropoid primates},
   Journal = {Journal of Human Evolution},
   Volume = {26},
   Number = {5-6},
   Pages = {441-457},
   Publisher = {Elsevier BV},
   Year = {1994},
   Month = {January},
   url = {http://dx.doi.org/10.1006/jhev.1994.1027},
   Abstract = {During the past century, many anthropologists have proposed
             that hominoid orthograde locomotion arose in an arboreal
             quadrupedal ancestor with highly mobile, low weight-bearing
             forelimbs. However, no quantitative data comparing kinematic
             and kinetic aspects of forelimb use during arboreal and
             terrestrial quadrupedalism have been available to evaluate
             such theories. In this preliminary study, a spider monkey
             and a baboon were videotaped in three planes while walking
             quadrupedally on an instrumented runway and a raised
             instrumented horizontal pole. Forelimb angles and substrate
             reaction force resultants were calculated for each animal on
             each substrate. The quantitative data presented here support
             previous models for the evolution of primate locomotion that
             were based on theoretical biomechanics and qualitative or
             anecdotal evidence. In addition, this study has revealed
             several previously undocumented accommodations to "arboreal"
             quadrupedal locomotion in these two primates. While walking
             on the pole, compared to travel on the ground, (1) both
             animals adopted a "crouched" forelimb posture, but only the
             spider monkey abducted its arm and ulnar deviated its hand;
             (2) both subjects have lower resultant forces on the
             forelimb due to lower absolute force magnitudes and changes
             in the timing of component peaks; and (3) both animals
             reduce and reorient transverse forces. Similar
             accommodations to arboreal travel by both subjects appear to
             be mechanical requirements of arboreal locomotion. However,
             differences may be due to morphological differences between
             the subjects, or to their divergent phylogenetic history.
             These results are used to explore potential explanations for
             the morphological differences between arboreal and
             terrestrial primate quadrupeds in terms of bone and joint
             strain and to evaluate models of primate locomotor
             evolution. © 1994 Academic Press. All rights
             reserved.},
   Doi = {10.1006/jhev.1994.1027},
   Key = {fds241069}
}

@article{fds330392,
   Author = {Schmitt, D and Larson, SG and Stern, JT},
   Title = {Serratus ventralis function in vervet monkeys (Cercopithecus
             aethiops): are primate quadrupeds unique?},
   Journal = {Journal of Zoology},
   Volume = {232},
   Number = {2},
   Pages = {215-230},
   Publisher = {WILEY},
   Year = {1994},
   Month = {January},
   url = {http://dx.doi.org/10.1111/j.1469-7998.1994.tb01570.x},
   Abstract = {The serratus ventralis in mammals is a fan‐shaped
             scapulo‐thoracic muscle that is believed by most
             morphologists both to support body weight and to rotate the
             scapula during quadrupedal locomotion. Electromyographic
             studies of this muscle in cats, dogs and opossums confirm
             the dual supportive and rotatory roles of the serratus
             ventralis. Although this muscle has been studied in several
             primate species, the concentration on arboreal locomotion
             has resulted in an inadequate data set to permit direct
             comparisons to non‐primate terrestrial quadrupeds. In
             order to provide a more comparable data set, we examined
             cranial, mid‐ and caudal thoracic regions of the serratus
             ventralis during terrestrial quadrupedalism in the vervet
             monkey, Cereopithecus aethiops. Our results indicate that
             the serratus ventralis does support the body during the
             stance phase of quadrupedalism in this primate. However,
             unlike several non‐primate mammals, it plays a relatively
             insignificant rotatory role during swing phase. Copyright ©
             1994, Wiley Blackwell. All rights reserved},
   Doi = {10.1111/j.1469-7998.1994.tb01570.x},
   Key = {fds330392}
}


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