Date of Graduation
8-2024
Document Type
Dissertation
Degree Name
Doctor of Philosophy in Biology (PhD)
Degree Level
Graduate
Department
Biological Sciences
Advisor/Mentor
Westerman, Erica L.
Committee Member
Nakanishi, Nagayasu
Second Committee Member
Siepielski, Adam M.
Third Committee Member
Shew, Woodrow L.
Keywords
Animal Behavior; Animal Communication; Evolutionary Biology
Abstract
Signaling behaviours are ubiquitous among animals with nervous systems and govern activities as diverse as fighting, fleeing from predators, foraging, and mating. Regardless of their purpose, signals need to be effectively generated, transmitted, and received in order to elicit the intended response from a receiver. The process by which signalers and receivers adapt their behaviours, the timing of their behaviours, and their sensory physiology to maximize the likelihood of effective communication is called signal optimization. Here, I address evolutionary and behavior-ecological mechanisms of signal optimization, primarily using butterflies as model species. In Chapter I, I investigate the effect of light quality on the colors that animals across the Metazoa have evolved to see. I show that terrestrial and aquatic animals have evolved different visual physiologies, and that habitat does not influence the colors that terrestrial animals can see. I then pivot from visual signals to multi-modal signals to investigate the synchronization of courtship and antennal sensitivity in the model butterfly Bicyclus anynana (Chapter II). I found that, although male B. anynana court in the evening, female B. anynana are most sensitive to odors in the morning. Finally, I examine the drivers of the evolution of the volumes of the optic lobe medulla, antennal lobe, and mushroom body calyx volume among North American butterflies (Chapter III). Here, I find evidence of an evolutionary tradeoff between relative optic lobe medullae and antennal lobe volumes, and that dorsal wing pattern complexity drives the evolution of optic lobe medulla volume amongst male butterflies. My research provides evidence for the evolution of sensory optimization across multiple taxonomic levels, and raises intriguing questions about the role of deviating from the behavioural synchronization expected under the sensory optimization paradigm. This work will form the basis for future studies on the evolution of animal visual systems, sensory physiology, and circadian rhythmicity in signaling behaviours.
Citation
Murphy, M. J. (2024). The Evolutionary Ecology Of Signal And Signal Reception Optimization, With A Focus On Butterflies (Lepidoptera: Rhopalocera). Graduate Theses and Dissertations Retrieved from https://scholarworks.uark.edu/etd/5533
