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| Publications of Elaine E. Guevara :recent first alphabetical combined listing:%% Journal Articles @article{fds346153, Author = {Guevara, EE and Steiper, ME}, Title = {Molecular phylogenetic analysis of the Papionina using concatenation and species tree methods.}, Journal = {Journal of Human Evolution}, Volume = {66}, Pages = {18-28}, Year = {2014}, Month = {January}, url = {http://dx.doi.org/10.1016/j.jhevol.2013.09.003}, Abstract = {The Papionina is a geographically widespread subtribe of African cercopithecid monkeys whose evolutionary history is of particular interest to anthropologists. The phylogenetic relationships among arboreal mangabeys (Lophocebus), baboons (Papio), and geladas (Theropithecus) remain unresolved. Molecular phylogenetic analyses have revealed marked gene tree incongruence for these taxa, and several recent concatenated phylogenetic analyses of multilocus datasets have supported different phylogenetic hypotheses. To address this issue, we investigated the phylogeny of the Lophocebus + Papio + Theropithecus group using concatenation methods, as well as alternative methods that incorporate gene tree heterogeneity to estimate a 'species tree.' Our compiled DNA sequence dataset was ∼56 kb pairs long and included 57 independent partitions. All analyses of concatenated alignments strongly supported a Lophocebus + Papio clade and a basal position for Theropithecus. The Bayesian concordance analysis supported the same phylogeny. A coalescent-based Bayesian method resulted in a very poorly resolved species tree. The topological agreement between concatenation and the Bayesian concordance analysis offers considerable support for a Lophocebus + Papio clade as the dominant relationship across the genome. However, the results of the Bayesian concordance analysis indicate that almost half the genome has an alternative history. As such, our results offer a well-supported phylogenetic hypothesis for the Papio/Lophocebus/Theropithecus trichotomy, while at the same time providing evidence for a complex evolutionary history that likely includes hybridization among lineages.}, Doi = {10.1016/j.jhevol.2013.09.003}, Key = {fds346153} } @article{fds346152, Author = {Perlman, RF and de Vries, D and Jacobs, RL and Holowka, NB and Pain, EL and Guevara, EE and Thompson, NE}, Title = {The gateway to anthropology in St. Louis.}, Journal = {Evolutionary Anthropology}, Volume = {24}, Number = {3}, Pages = {101-103}, Year = {2015}, Month = {May}, url = {http://dx.doi.org/10.1002/evan.21450}, Doi = {10.1002/evan.21450}, Key = {fds346152} } @article{fds346151, Author = {Perlman, RF and Nishimura, AC and Mongle, CS and Kling, K and Guevara, EE and Arslanian, K}, Title = {Life's a peach for anthropologists in atlanta.}, Journal = {Evolutionary Anthropology}, Volume = {25}, Number = {3}, Pages = {81-83}, Year = {2016}, Month = {May}, url = {http://dx.doi.org/10.1002/evan.21493}, Doi = {10.1002/evan.21493}, Key = {fds346151} } @article{fds346150, Author = {Guevara, EE and Veilleux, CC and Saltonstall, K and Caccone, A and Mundy, NI and Bradley, BJ}, Title = {Potential arms race in the coevolution of primates and angiosperms: brazzein sweet proteins and gorilla taste receptors.}, Journal = {American Journal of Physical Anthropology}, Volume = {161}, Number = {1}, Pages = {181-185}, Year = {2016}, Month = {September}, url = {http://dx.doi.org/10.1002/ajpa.23046}, Abstract = {<h4>Objectives</h4>We explored whether variation in the sweet taste receptor protein T1R3 in primates could contribute to differences in sweet taste repertoire among species, potentially reflecting coevolution with local plants. Specifically, we examined which primates are likely to be sweet "tasters" of brazzein, a protein found in the fruit of the African plant Pentadiplandra brazzeana that tastes intensely sweet to humans, but provides little energy. Sweet proteins like brazzein are thought to mimic the taste of sugars to entice seed dispersers. We examined the evolution of T1R3 and assessed whether primates are likely "deceived" by such biochemical mimicry.<h4>Methods</h4>Using published and new sequence data for TAS1R3, we characterized 57 primates and other mammals at the two amino acid sites necessary to taste brazzein to determine which species are tasters. We further used dN/dS-based methods to look for statistical evidence of accelerated evolution in this protein across primate lineages.<h4>Results</h4>The taster genotype is shared across most catarrhines, suggesting that most African primates can be "tricked" into eating and dispersing P. brazzeana's seeds for little caloric gain. Western gorillas (Gorilla gorilla), however, exhibit derived mutations at the two brazzein-critical positions, and although fruit is a substantial portion of the western gorilla diet, they have not been observed to eat P. brazzeana. Our analyses of protein evolution found no signature of positive selection on TAS1R3 along the gorilla lineage.<h4>Discussion</h4>We propose that the gorilla-specific mutations at the TAS1R3 locus encoding T1R3 could be a counter-adaptation to the false sweet signal of brazzein.}, Doi = {10.1002/ajpa.23046}, Key = {fds346150} } @article{fds346149, Author = {Bradley, BJ and Snowdon, CT and McGrew, WC and Lawler, RR and Guevara, EE and McIntosh, A and O'Connor, T}, Title = {Non-human primates avoid the detrimental effects of prenatal androgen exposure in mixed-sex litters: combined demographic, behavioral, and genetic analyses.}, Journal = {American Journal of Primatology}, Volume = {78}, Number = {12}, Pages = {1304-1315}, Year = {2016}, Month = {December}, url = {http://dx.doi.org/10.1002/ajp.22583}, Abstract = {Producing single versus multiple births has important life history trade-offs, including the potential benefits and risks of sharing a common in utero environment. Sex hormones can diffuse through amniotic fluid and fetal membranes, and females with male littermates risk exposure to high levels of fetal testosterone, which are shown to have masculinizing effects and negative fitness consequences in many mammals. Whereas most primates give birth to single offspring, several New World monkey and strepsirrhine species regularly give birth to small litters. We examined whether neonatal testosterone exposure might be detrimental to females in mixed-sex litters by compiling data from long-term breeding records for seven primate species (Saguinus oedipus; Varecia variegata, Varecia rubra, Microcebus murinis, Mirza coquereli, Cheirogaleus medius, Galago moholi). Litter sex ratios did not differ from the expected 1:2:1 (MM:MF:FF for twins) and 1:2:2:1 (MMM:MMF:MFF:FFF for triplets). Measures of reproductive success, including female survivorship, offspring-survivorship, and inter-birth interval, did not differ between females born in mixed-sex versus all-female litters, indicating that litter-producing non-human primates, unlike humans and rodents, show no signs of detrimental effects from androgen exposure in mixed sex litters. Although we found no evidence for CYP19A1 gene duplications-a hypothesized mechanism for coping with androgen exposure-aromatase protein evolution shows patterns of convergence among litter-producing taxa. That some primates have effectively found a way to circumvent a major cost of multiple births has implications for understanding variation in litter size and life history strategies across mammals.}, Doi = {10.1002/ajp.22583}, Key = {fds346149} } @article{fds346148, Author = {Guevara, EE and Chen-Kraus, C and Jacobs, RL and Baden, AL}, Title = {Celebrating fifty years of research at the Duke Lemur Center.}, Journal = {Evolutionary Anthropology}, Volume = {26}, Number = {2}, Pages = {47-48}, Year = {2017}, Month = {April}, url = {http://dx.doi.org/10.1002/evan.21521}, Doi = {10.1002/evan.21521}, Key = {fds346148} } @article{fds346147, Author = {Staes, N and Sherwood, CC and Wright, K and de Manuel, M and Guevara, EE and Marques-Bonet, T and Krützen, M and Massiah, M and Hopkins, WD and Ely, JJ and Bradley, BJ}, Title = {FOXP2 variation in great ape populations offers insight into the evolution of communication skills.}, Journal = {Scientific Reports}, Volume = {7}, Number = {1}, Pages = {16866}, Year = {2017}, Month = {December}, url = {http://dx.doi.org/10.1038/s41598-017-16844-x}, Abstract = {The gene coding for the forkhead box protein P2 (FOXP2) is associated with human language disorders. Evolutionary changes in this gene are hypothesized to have contributed to the emergence of speech and language in the human lineage. Although FOXP2 is highly conserved across most mammals, humans differ at two functional amino acid substitutions from chimpanzees, bonobos and gorillas, with an additional fixed substitution found in orangutans. However, FOXP2 has been characterized in only a small number of apes and no publication to date has examined the degree of natural variation in large samples of unrelated great apes. Here, we analyzed the genetic variation in the FOXP2 coding sequence in 63 chimpanzees, 11 bonobos, 48 gorillas, 37 orangutans and 2 gibbons and observed undescribed variation in great apes. We identified two variable polyglutamine microsatellites in chimpanzees and orangutans and found three nonsynonymous single nucleotide polymorphisms, one in chimpanzees, one in gorillas and one in orangutans with derived allele frequencies of 0.01, 0.26 and 0.29, respectively. Structural and functional protein modeling indicate a biochemical effect of the substitution in orangutans, and because of its presence solely in the Sumatran orangutan species, the mutation may be associated with reported population differences in vocalizations.}, Doi = {10.1038/s41598-017-16844-x}, Key = {fds346147} } @article{fds346308, Author = {Guevara, EE and Frankel, DC and Ranaivonasy, J and Richard, AF and Ratsirarson, J and Lawler, RR and Bradley, BJ}, Title = {A simple, economical protocol for DNA extraction and amplification where there is no lab}, Journal = {Conservation Genetics Resources}, Volume = {10}, Number = {1}, Pages = {119-125}, Year = {2018}, Month = {March}, url = {http://dx.doi.org/10.1007/s12686-017-0758-5}, Abstract = {Genetic analyses are well suited to address many research questions in the study of wild populations, yet species of interest often have distributions that are geographically distant from molecular laboratories, necessitating potentially lengthy transport of biological specimens. Performing basic genetic analyses on site would avoid the project delays and risks of sample quality decline associated with transport, as well as allow original specimens to remain in the country of origin. Further, diagnostic genetic assays performed in the field could provide real-time information allowing for more nimble adjustments to research plans and use of resources. To this end, we developed protocols for reliably performing front-end genetics bench work in the field, without the requirements of electricity or permanent shelter. We validated these protocols on buccal swabs collected during routine capturing of sifaka lemurs (Propithecus verreauxi) at Bezà Mahafaly Special Reserve in Southwest Madagascar and faecal samples collected from captive sifakas (P. coquereli) at the Duke Lemur Center. Our basic protocol pipeline involves a chelating resin based DNA extraction followed by whole genome amplification or polymerase chain reaction using reagents stored at ambient temperature and portable, compact equipment powered by a lightweight solar panel. We achieved a high success rate (CloseSPigtSPi80%) in downstream procedures, demonstrating the promise of such protocols for performing basic genetic analyses in a broad range of field situations.}, Doi = {10.1007/s12686-017-0758-5}, Key = {fds346308} } @article{fds346146, Author = {Guevara, EE and Lawler, RR}, Title = {Epigenetic Clocks.}, Journal = {Evolutionary Anthropology}, Volume = {27}, Number = {6}, Pages = {256-260}, Year = {2018}, Month = {November}, url = {http://dx.doi.org/10.1002/evan.21745}, Abstract = {Recent research has revealed clock-like patterns of epigenetic change across the life span in humans. Models describing these epigenetic changes have been dubbed "epigenetic clocks," and they can not only predict chronological age but also reveal biological age, which measures physiological homeostasis and deterioration over the life span. Comparative studies of the epigenetic clocks of different primate species are likely to provide insights into the evolution of life history schedules, as well as shed light on the physiological and genetic bases of aging and aging-related diseases. Chronological age estimation using clock-based calculators may also offer biological anthropologists a useful tool for applying to forensic and demographic studies.}, Doi = {10.1002/evan.21745}, Key = {fds346146} } @article{fds346145, Author = {Webster, T and Guevara, E and Lawler, R and Bradley, B}, Title = {Successful exome capture and sequencing in lemurs using human baits}, Year = {2018}, Month = {December}, url = {http://dx.doi.org/10.1101/490839}, Abstract = {ABSTRACT Objectives We assessed the efficacy of exome capture in lemurs using commercially available human baits. Materials and Methods We used two human kits (Nimblegen SeqCap EZ Exome Probes v2.0; IDT xGen Exome Research Panel v1.0) to capture and sequence the exomes of wild Verreaux’s sifakas ( Propithecus verreauxi, n = 8), a lemur species distantly related to humans. For comparison, we also captured exomes of a primate species more closely related to humans ( Macaca mulatta, n= 4). We mapped reads to both the human reference assembly and the most closely related reference for each species before calling variants. We used measures of mapping quality and read coverage to compare capture success. Results We observed high and comparable mapping qualities for both species when mapped to their respective nearest-relative reference genomes. When investigating breadth of coverage, we found greater capture success in macaques than sifakas using both nearest-relative and human assemblies. Exome capture in sifakas was still highly successful with more than 90% of annotated coding sequence in the sifaka reference genome captured, and 80% sequenced to a depth greater than 7x using Nimblegen baits. However, this success depended on probe design: the use of IDT probes resulted in substantially less callable sequence at low-to-moderate depths. Discussion Overall, we demonstrate successful exome capture in lemurs using human baits, though success differed between kits tested. These results indicate that exome capture is an effective and economical genomic method of broad utility to evolutionary primatologists working across the entire primate order.}, Doi = {10.1101/490839}, Key = {fds346145} } @article{fds346144, Author = {Singh, SV and Staes, N and Guevara, EE and Schapiro, SJ and Ely, JJ and Hopkins, WD and Sherwood, CC and Bradley, BJ}, Title = {Evolution of ASPM coding variation in apes and associations with brain structure in chimpanzees.}, Journal = {Genes, Brain, and Behavior}, Volume = {18}, Number = {7}, Pages = {e12582}, Year = {2019}, Month = {September}, url = {http://dx.doi.org/10.1111/gbb.12582}, Abstract = {Studying genetic mechanisms underlying primate brain morphology can provide insight into the evolution of human brain structure and cognition. In humans, loss-of-function mutations in the gene coding for ASPM (Abnormal Spindle Microtubule Assembly) have been associated with primary microcephaly, which is defined by a significantly reduced brain volume, intellectual disability and delayed development. However, less is known about the effects of common ASPM variation in humans and other primates. In this study, we characterized the degree of coding variation at ASPM in a large sample of chimpanzees (N = 241), and examined potential associations between genotype and various measures of brain morphology. We identified and genotyped five non-synonymous polymorphisms in exons 3 (V588G), 18 (Q2772K, K2796E, C2811Y) and 27 (I3427V). Using T1-weighted magnetic resonance imaging of brains, we measured total brain volume, cerebral gray and white matter volume, cerebral ventricular volume, and cortical surface area in the same chimpanzees. We found a potential association between ASPM V588G genotype and cerebral ventricular volume but not with the other measures. Additionally, we found that chimpanzee, bonobo, and human lineages each independently show a signature of accelerated ASPM protein evolution. Overall, our results suggest the potential effects of ASPM variation on cerebral cortical development, and emphasize the need for further functional studies. These results are the first evidence suggesting ASPM variation might play a role in shaping natural variation in brain structure in nonhuman primates.}, Doi = {10.1111/gbb.12582}, Key = {fds346144} } @article{fds352546, Author = {Guevara, EE and Lawler, RR and Staes, N and White, CM and Sherwood, CC and Ely, JJ and Hopkins, WD and Bradley, BJ}, Title = {Age-associated epigenetic change in chimpanzees and humans.}, Journal = {Philosophical Transactions of the Royal Society of London. Series B, Biological Sciences}, Volume = {375}, Number = {1811}, Pages = {20190616}, Year = {2020}, Month = {November}, url = {http://dx.doi.org/10.1098/rstb.2019.0616}, Abstract = {Methylation levels have been shown to change with age at sites across the human genome. Change at some of these sites is so consistent across individuals that it can be used as an 'epigenetic clock' to predict an individual's chronological age to within a few years. Here, we examined how the pattern of epigenetic ageing in chimpanzees compares with humans. We profiled genome-wide blood methylation levels by microarray for 113 samples from 83 chimpanzees aged 1-58 years (26 chimpanzees were sampled at multiple ages during their lifespan). Many sites (greater than 65 000) showed significant change in methylation with age and around one-third (32%) of these overlap with sites showing significant age-related change in humans. At over 80% of sites showing age-related change in both species, chimpanzees displayed a significantly faster rate of age-related change in methylation than humans. We also built a chimpanzee-specific epigenetic clock that predicted age in our test dataset with a median absolute deviation from known age of only 2.4 years. However, our chimpanzee clock showed little overlap with previously constructed human clocks. Methylation at CpGs comprising our chimpanzee clock showed moderate heritability. Although the use of a human microarray for profiling chimpanzees biases our results towards regions with shared genomic sequence between the species, nevertheless, our results indicate that there is considerable conservation in epigenetic ageing between chimpanzees and humans, but also substantial divergence in both rate and genomic distribution of ageing-associated sites. This article is part of the theme issue 'Evolution of the primate ageing process'.}, Doi = {10.1098/rstb.2019.0616}, Key = {fds352546} } @article{fds355361, Author = {Staes, N and Guevara, EE and Helsen, P and Eens, M and Stevens, JMG}, Title = {The Pan social brain: An evolutionary history of neurochemical receptor genes and their potential impact on sociocognitive differences.}, Journal = {Journal of Human Evolution}, Volume = {152}, Pages = {102949}, Year = {2021}, Month = {March}, url = {http://dx.doi.org/10.1016/j.jhevol.2021.102949}, Abstract = {Humans have unique cognitive capacities that, compared with apes, are not only simply expressed as a higher level of general intelligence, but also as a quantitative difference in sociocognitive skills. Humans' closest living relatives, bonobos (Pan paniscus), and chimpanzees (Pan troglodytes), show key between-species differences in social cognition despite their close phylogenetic relatedness, with bonobos arguably showing greater similarities to humans. To better understand the evolution of these traits, we investigate the neurochemical mechanisms underlying sociocognitive skills by focusing on variation in genes encoding proteins with well-documented roles in mammalian social cognition: the receptors for vasopressin (AVPR1A), oxytocin (OXTR), serotonin (HTR1A), and dopamine (DRD2). Although these genes have been well studied in humans, little is known about variation in these genes that may underlie differences in social behavior and cognition in apes. We comparatively analyzed sequence data for 33 bonobos and 57 chimpanzees, together with orthologous sequence data for other apes. In all four genes, we describe genetic variants that alter the amino acid sequence of the respective receptors, raising the possibility that ligand binding or signal transduction may be impacted. Overall, bonobos show 57% more fixed substitutions than chimpanzees compared with the ancestral Pan lineage. Chimpanzees, show 31% more polymorphic coding variation, in line with their larger historical effective population size estimates and current wider distribution. An extensive literature review comparing allelic changes in Pan with known human behavioral variants revealed evidence of homologous evolution in bonobos and humans (OXTR rs4686301(T) and rs237897(A)), while humans and chimpanzees shared OXTR rs2228485(A), DRD2 rs6277(A), and DRD2 rs11214613(A) to the exclusion of bonobos. Our results offer the first in-depth comparison of neurochemical receptor gene variation in Pan and put forward new variants for future behavior-genotype association studies in apes, which can increase our understanding of the evolution of social cognition in modern humans.}, Doi = {10.1016/j.jhevol.2021.102949}, Key = {fds355361} } @article{fds355947, Author = {Guevara, EE and Webster, TH and Lawler, RR and Bradley, BJ and Greene, LK and Ranaivonasy, J and Ratsirarson, J and Harris, RA and Liu, Y and Murali, S and Raveendran, M and Hughes, DST and Muzny, DM and Yoder, AD and Worley, KC and Rogers, J}, Title = {Comparative genomic analysis of sifakas (Propithecus) reveals selection for folivory and high heterozygosity despite endangered status.}, Journal = {Science Advances}, Volume = {7}, Number = {17}, Pages = {eabd2274}, Year = {2021}, Month = {April}, url = {http://dx.doi.org/10.1126/sciadv.abd2274}, Abstract = {Sifakas (genus Propithecus) are critically endangered, large-bodied diurnal lemurs that eat leaf-based diets and show corresponding anatomical and microbial adaptations to folivory. We report on the genome assembly of Coquerel's sifaka (P. coquereli) and the resequenced genomes of Verreaux's (P. verreauxi), the golden-crowned (P. tattersalli), and the diademed (P. diadema) sifakas. We find high heterozygosity in all sifakas compared with other primates and endangered mammals. Demographic reconstructions nevertheless suggest declines in effective population size beginning before human arrival on Madagascar. Comparative genomic analyses indicate pervasive accelerated evolution in the ancestral sifaka lineage affecting genes in several complementary pathways relevant to folivory, including nutrient absorption and xenobiotic and fatty acid metabolism. Sifakas show convergent evolution at the level of the pathway, gene family, gene, and amino acid substitution with other folivores. Although sifakas have relatively generalized diets, the physiological challenges of habitual folivory likely led to strong selection.}, Doi = {10.1126/sciadv.abd2274}, Key = {fds355947} } @article{fds356173, Author = {Guevara, EE and Hopkins, WD and Hof, PR and Ely, JJ and Bradley, BJ and Sherwood, CC}, Title = {Comparative analysis reveals distinctive epigenetic features of the human cerebellum.}, Journal = {Plos Genetics}, Volume = {17}, Number = {5}, Pages = {e1009506}, Year = {2021}, Month = {May}, url = {http://dx.doi.org/10.1371/journal.pgen.1009506}, Abstract = {Identifying the molecular underpinnings of the neural specializations that underlie human cognitive and behavioral traits has long been of considerable interest. Much research on human-specific changes in gene expression and epigenetic marks has focused on the prefrontal cortex, a brain structure distinguished by its role in executive functions. The cerebellum shows expansion in great apes and is gaining increasing attention for its role in motor skills and cognitive processing, including language. However, relatively few molecular studies of the cerebellum in a comparative evolutionary context have been conducted. Here, we identify human-specific methylation in the lateral cerebellum relative to the dorsolateral prefrontal cortex, in a comparative study with chimpanzees (Pan troglodytes) and rhesus macaques (Macaca mulatta). Specifically, we profiled genome-wide methylation levels in the three species for each of the two brain structures and identified human-specific differentially methylated genomic regions unique to each structure. We further identified which differentially methylated regions (DMRs) overlap likely regulatory elements and determined whether associated genes show corresponding species differences in gene expression. We found greater human-specific methylation in the cerebellum than the dorsolateral prefrontal cortex, with differentially methylated regions overlapping genes involved in several conditions or processes relevant to human neurobiology, including synaptic plasticity, lipid metabolism, neuroinflammation and neurodegeneration, and neurodevelopment, including developmental disorders. Moreover, our results show some overlap with those of previous studies focused on the neocortex, indicating that such results may be common to multiple brain structures. These findings further our understanding of the cerebellum in human brain evolution.}, Doi = {10.1371/journal.pgen.1009506}, Key = {fds356173} } @article{fds366563, Author = {Guevara, EE and Greene, LK and Blanco, MB and Farmer, C and Ranaivonasy, J and Ratsirarson, J and Mahefarisoa, KL and Rajaonarivelo, T and Rakotondrainibe, HH and Junge, RE and Williams, CV and Rambeloson, E and Rasoanaivo, HA and Rahalinarivo, V and Andrianandrianina, LH and Clayton, JB and Rothman, RS and Lawler, RR and Bradley, BJ and Yoder, AD}, Title = {Molecular adaptation to folivory and the conservation implications for Madagascar’s lemurs}, Year = {2021}, Month = {July}, url = {http://dx.doi.org/10.1101/2021.07.06.451309}, Abstract = {<jats:title>Abstract</jats:title><jats:p>Folivory evolved independently at least three times over the last 40 million years among Madagascar’s lemurs. Many extant lemuriform folivores exist in sympatry in Madagascar’s remaining forests. These species avoid feeding competition by adopting different dietary strategies within folivory, reflected in behavioral, morphological, and microbiota diversity across species. These conditions make lemurs an ideal study system for understanding adaptation to leaf-eating. Most folivorous lemurs are also highly endangered. The significance of folivory for conservation outlook is complex. Though generalist folivores may be relatively well equipped to survive habitat disturbance, specialist folivores occupying narrow dietary niches may be less resilient. Characterizing the genetic bases of adaptation to folivory across species and lineages can provide insights into their differential physiology and potential to resist habitat change. We recently reported accelerated genetic change in<jats:italic>RNASE1</jats:italic>, a gene encoding an enzyme (RNase 1) involved in molecular adaptation in mammalian folivores, including various monkeys and sifakas (genus<jats:italic>Propithecus</jats:italic>; family Indriidae). Here, we sought to assess whether other lemurs, including phylogenetically and ecologically diverse folivores, might show parallel adaptive change in<jats:italic>RNASE1</jats:italic>that could underlie a capacity for efficient folivory. We characterized<jats:italic>RNASE1</jats:italic>in 21 lemur species representing all five families and members of the three extant folivorous lineages: 1) bamboo lemurs (family Lemuridae), 2) sportive lemurs (family Lepilemuridae), and 3) indriids (family Indriidae). We found pervasive sequence change in<jats:italic>RNASE1</jats:italic>across all indriids, a d<jats:sub>N</jats:sub>/d<jats:sub>S</jats:sub>value > 3 in this clade, and evidence for shared change in isoelectric point, indicating altered enzymatic function. Sportive and bamboo lemurs, in contrast, showed more modest sequence change. The greater change in indriids may reflect a shared strategy emphasizing complex gut morphology and microbiota to facilitate folivory. This case study illustrates how genetic analysis may reveal differences in functional traits that could influence species’ ecology and, in turn, their resilience to habitat change. Moreover, our results support the contention that not all primate folivores are built the same and highlight the need to avoid generalizations about dietary guild in considering conservation outlook, particularly in lemurs where such diversity in folivory has probably led to extensive specialization via niche partitioning.</jats:p>}, Doi = {10.1101/2021.07.06.451309}, Key = {fds366563} } @article{fds363984, Author = {Guevara, EE and Hopkins, WD and Hof, PR and Ely, JJ and Bradley, BJ and Sherwood, CC}, Title = {Epigenetic ageing of the prefrontal cortex and cerebellum in humans and chimpanzees.}, Journal = {Epigenetics}, Volume = {17}, Number = {12}, Pages = {1774-1785}, Year = {2022}, Month = {December}, url = {http://dx.doi.org/10.1080/15592294.2022.2080993}, Abstract = {Epigenetic age has emerged as an important biomarker of biological ageing. It has revealed that some tissues age faster than others, which is vital to understanding the complex phenomenon of ageing and developing effective interventions. Previous studies have demonstrated that humans exhibit heterogeneity in pace of epigenetic ageing among brain structures that are consistent with differences in structural and microanatomical deterioration. Here, we add comparative data on epigenetic brain ageing for chimpanzees, humans' closest relatives. Such comparisons can further our understanding of which aspects of human ageing are evolutionarily conserved or specific to our species, especially given that humans are distinguished by a long lifespan, large brain, and, potentially, more severe neurodegeneration with age. Specifically, we investigated epigenetic ageing of the dorsolateral prefrontal cortex and cerebellum, of humans and chimpanzees by generating genome-wide CpG methylation data and applying established epigenetic clock algorithms to produce estimates of biological age for these tissues. We found that both species exhibit relatively slow epigenetic ageing in the brain relative to blood. Between brain structures, humans show a faster rate of epigenetic ageing in the dorsolateral prefrontal cortex compared to the cerebellum, which is consistent with previous findings. Chimpanzees, in contrast, show comparable rates of epigenetic ageing in the two brain structures. Greater epigenetic change in the human dorsolateral prefrontal cortex compared to the cerebellum may reflect both the protracted development of this structure in humans and its greater age-related vulnerability to neurodegenerative pathology.}, Doi = {10.1080/15592294.2022.2080993}, Key = {fds363984} } @article{fds373899, Author = {Guevara, E and Gopalan, S and Massey, DJ and Adegboyega, M and Zhou, W and Solis, A and Anaya, AD and Churchill, SE and Feldblum, J and Lawler, RR}, Title = {Getting it right: Teaching undergraduate biology to undermine racial essentialism.}, Journal = {Biology Methods and Protocols}, Volume = {8}, Number = {1}, Pages = {bpad032}, Publisher = {Oxford University Press (OUP)}, Year = {2023}, Month = {January}, url = {http://dx.doi.org/10.1093/biomethods/bpad032}, Abstract = {How we teach human genetics matters for social equity. The biology curriculum appears to be a crucial locus of intervention for either reinforcing or undermining students' racial essentialist views. The Mendelian genetic models dominating textbooks, particularly in combination with racially inflected language sometimes used when teaching about monogenic disorders, can increase middle and high school students' racial essentialism and opposition to policies to increase equity. These findings are of particular concern given the increasing spread of racist misinformation online and the misappropriation of human genomics research by white supremacists, who take advantage of low levels of genetics literacy in the general public. Encouragingly, however, teaching updated information about the geographical distribution of human genetic variation and the complex, multifactorial basis of most human traits, reduces students' endorsement of racial essentialism. The genetics curriculum is therefore a key tool in combating misinformation and scientific racism. Here, we describe a framework and example teaching materials for teaching students key concepts in genetics, human evolutionary history, and human phenotypic variation at the undergraduate level. This framework can be flexibly applied in biology and anthropology classes and adjusted based on time availability. Our goal is to provide undergraduate-level instructors with varying levels of expertise with a set of evidence-informed tools for teaching human genetics to combat scientific racism, including an evolving set of instructional resources, as well as learning goals and pedagogical approaches. Resources can be found at https://noto.li/YIlhZ5. Additionally, we hope to generate conversation about integrating modern genetics into the undergraduate curriculum, in light of recent findings about the risks and opportunities associated with teaching genetics.}, Doi = {10.1093/biomethods/bpad032}, Key = {fds373899} } %% Papers Presented/Symposia/Abstracts @article{fds346154, Author = {Guevara, EEG and Steiper, ME}, Title = {Analysis of multi-locus sequence data indicates complex speciation in the evolutionary history of the Papionina}, Journal = {American Journal of Physical Anthropology}, Volume = {150}, Pages = {139-140}, Publisher = {WILEY-BLACKWELL}, Year = {2013}, Month = {January}, Key = {fds346154} } | ||
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