Date of Award
1999
Document Type
Dissertation
Degree Name
Doctor of Philosophy (PhD)
Department
Psychology
Abstract
A largely unexplored area in behavioral ecology is the inherent conflict between sleep and wakefulness. Wakefulness is an adaptive state that allows animals to interact with their environment, yet its efficacy is contingent upon prior sleep, a vulnerable state of reduced responsiveness. Birds and aquatic mammals have essentially side-stepped this problem by simultaneously engaging in both wakefulness and sleep; one cerebral hemisphere sleeps while the other remains awake, a unique state known as unihemispheric sleep. In aquatic mammals, unihemispheric sleep allows sleep and sufacing to breathe to occur concurrently. However, the adaptive function of avian unihemispheric sleep has been unclear. Herein we test the hypothesis that birds use unihemispheric: sleep to watch for approaching predators. In a series of behavioral and electrophysiological studies we show that mallard ducks ( Anas platyrhynchos ) increase their use of unihemispheric sleep when sleeping under riskier situations. These results are the first to demonstrate behavioral plasticity in unihemispheric sleep. In a second set of experiments, we demonstrate that pigeons ( Columba livia ) also use unihemispheric sleep in a manner consistent with a predator detection function. Finally, the results from mallards and pigeons are incorporated within a comprehensive review on unihemispheric sleep.
Recommended Citation
Rattenborg, Niels Christian, "Plasticity In Avian Unihemispheric Sleep: An Antipredator Function" (1999). All-Inclusive List of Electronic Theses and Dissertations. 846.
https://scholars.indianastate.edu/etds/846