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Full-Text Articles in Behavior and Ethology
Testing Assumptions Of Coevolution In An Egg-Rejecting Brood Parasite Host: Uncovering Sensory, Cognitive, And Evolutionary Drivers Of Responses To Parasitism In American Robins (Turdus Migratorius), Rebecca Croston
Dissertations, Theses, and Capstone Projects
Hosts of brood parasitic birds face fitness costs associated with rearing unrelated offspring. In response, the recognition and rejection of parasitic eggs is a common host defense. Brown-headed cowbirds (Molothrus ater) challenge coevolutionary theory, because although they exploit over 200 host species, they lay non-mimetic eggs, and most hosts do not combat cowbird parasitism with egg rejection. American robins (Turdus migratorius) are one of a handful of cowbird hosts known to recognize and remove cowbird eggs from the nest. I addressed the mechanistic and evolutionary drivers of egg rejection in this host species, by disentangling the roles of spectral tuning …
How Important Is Land-Based Foraging To Polar Bears (Ursus Maritimus) During The Ice-Free Season In Western Hudson Bay? An Examination Of Dietary Shifts, Compositional Patterns, Behavioral Observations And Energetic Contributions, Linda J. Gormezano
Dissertations, Theses, and Capstone Projects
Trophic mismatches between predators and their prey are increasing as climate change causes decoupling of phenological relationships. Predators linked to the life histories of a particular prey will have a more difficult time persisting through environmental change unless they can alter their behavior to maintain the historical match or possess the ability to pursue alternate prey. Arctic predators typically possess flexible foraging strategies to survive in the labile environment, however, quantifying the limits of those strategies can be difficult when life history information is incomplete. In such cases, piecing together different aspects of a predator's foraging behavior, particularly when environmental …