Stephen Nowicki, Professor  

Stephen Nowicki

Our lab studies animal communication, asking both proximate and ultimate questions about how signaling systems function and how they evolve. Most of our work is done with birds, although lab members have studied a variety of other taxa. One major theme that runs through our work is to understand how signal reliability (“honesty”) is maintained in the face of the competing evolutionary interests of signal senders and receivers. We use both laboratory experiments and field-based analyses to test hypotheses about the costs of signal production, which theory suggests are necessary to maintain reliability. For example, we have demonstrated that the reliability of birdsong as a signal of quality in the context of mate choice is maintained by variation in the response of young birds to early developmental stress, which in turn affects brain development and song learning. Another theme that runs through our work concerns how animals themselves perceive signals, in particular the role of categorical perception in communication. Our work here began with birdsong, for example demonstrating context-dependent variation in category boundaries that define the smallest acoustic units of song (“notes”), and identifying categorical responses of neurons in the “song system” of the brain to variation in those notes. More recently, we have begun to study categorical perception in visual signaling, demonstrating for example that the carotenoid-based orange-red coloration commonly used in assessment signaling may be perceived categorically. This finding illustrates the connection between our interests in perception and reliability, given that canonical models of reliability assume continuous perception.

Education:
Ph.D., Cornell University, 1984
M.S., Tufts University, 1978
B.S., Tufts University, 1976

Office Location: 137 Biological Sciences Building, 130 Science Drive, Durham, NC 27708
Office Phone: +1 919 684 6950
Email Address: snowicki@duke.edu
Web Page: http://www.biology.duke.edu/nowicki/
Additional Web Page: http://www.nowickilab.org

Specialties:
Organismal Biology and Behavior
Neuroscience
Evolution
Ecology and Population Biology

Research Categories: Function, structure, and evolution of animal signaling systems

Research Description: Our lab studies animal communication, asking both proximate and ultimate questions about how signaling systems function and how they evolve. Most of our work is done with birds, although lab members have studied a variety of other taxa. One major theme that runs through our work is to understand how signal reliability (“honesty”) is maintained in the face of the competing evolutionary interests of signal senders and receivers. We use both laboratory experiments and field-based analyses to test hypotheses about the costs of signal production, which theory suggests are necessary to maintain reliability. For example, we have demonstrated that the reliability of birdsong as a signal of quality in the context of mate choice is maintained by variation in the response of young birds to early developmental stress, which in turn affects brain development and song learning. Another theme that runs through our work concerns how animals themselves perceive signals, in particular the role of categorical perception in communication. Our work here began with birdsong, for example demonstrating context-dependent variation in category boundaries that define the smallest acoustic units of song (“notes”), and identifying categorical responses of neurons in the “song system” of the brain to variation in those notes. More recently, we have begun to study categorical perception in visual signaling, demonstrating for example that the carotenoid-based orange-red coloration commonly used in assessment signaling may be perceived categorically.

Areas of Interest:
evolution of animal signaling systems
neural basis of communication

Recent Publications   (More Publications)   (search)

  1. Caves, EM; Davis, AL; Nowicki, S; Johnsen, S, Backgrounds and the evolution of visual signals., Trends in ecology & evolution, vol. 39 no. 2 (February, 2024), pp. 188-198 [doi]  [abs].
  2. Searcy, WA; Nowicki, S, Human-wild bird cooperation., Science (New York, N.Y.), vol. 382 no. 6675 (December, 2023), pp. 1124-1125 [doi]  [abs].
  3. Searcy, WA; Chronister, LM; Nowicki, S, Syntactic rules predict song type matching in a songbird, Behavioral Ecology and Sociobiology, vol. 77 no. 1 (January, 2023) [doi]  [abs].
  4. Peters, S; Soha, J; Searcy, WA; Nowicki, S, Are song sequencing rules learned by song sparrows?, Animal Behaviour, vol. 192 (October, 2022), pp. 75-84 [doi]  [abs].
  5. Davis, A; Zipple, MN; Diaz, D; Peters, S; Nowicki, S; Johnsen, S, Influence of visual background on discrimination of signal-relevant colours in zebra finches (Taeniopygia guttata)., Proceedings. Biological sciences, vol. 289 no. 1976 (June, 2022), pp. 20220756 [doi]  [abs].