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Full-Text Articles in Life Sciences
Cognitive Models Of Defense Behaviors In Hosts Of Brood Parasites, Thomas J. Manna
Cognitive Models Of Defense Behaviors In Hosts Of Brood Parasites, Thomas J. Manna
Dissertations, Theses, and Capstone Projects
Social parasites exploit the behavioral repertoire of their hosts for their own benefit, thereby reducing host reproductive success. Whether and how hosts respond to prevent, reduce, or eliminate the costs of parasitism requires the characterization of host cognitive algorithms in response to parasites. In this dissertation, I review the suite of the defense behaviors and decision rules of hosts targeted by avian and insect brood parasites, and present new experimental data on the detection of parasitism through the visual system of focal host species. In Chapter 1, I review extensive data already accumulated to isolate the cognitive mechanisms used by …
Positive Interactions Among Foraging Seabirds, Marine Mammals And Fishes And Implications For Their Conservation, Richard R. Veit, Nancy M. Harrison
Positive Interactions Among Foraging Seabirds, Marine Mammals And Fishes And Implications For Their Conservation, Richard R. Veit, Nancy M. Harrison
Publications and Research
There is increasing recognition of the importance of “positive interactions” among species in structuring communities. For seabirds, an important kind of positive interaction is the use of birds of the same species, birds of other species, and other marine predators such as cetaceans, seals and fishes as cues to the presence of prey. The process by which a single bird uses, say, a feeding flock of birds as a cue to the presence of prey is called “local enhancement” or “facilitation.” There are subtly different uses of each of these terms, but the issue we address here is the ubiquity …
Now You See It, Now You Don’T: Flushing Hosts Prior To Experimentation Can Predict Their Responses To Brood Parasitism, Daniel Hanley, Peter Samas, Josef Heryán, Mark E. Hauber, Tomáš Grim
Now You See It, Now You Don’T: Flushing Hosts Prior To Experimentation Can Predict Their Responses To Brood Parasitism, Daniel Hanley, Peter Samas, Josef Heryán, Mark E. Hauber, Tomáš Grim
Publications and Research
Brood parasitic birds lay their eggs in other birds’ nests, leaving hosts to raise their offspring. To understand parasite-host coevolutionary arms races, many studies have examined host responses to experimentally introduced eggs. However, attending parents often need to be flushed from their nests to add experimental eggs. If these birds witness parasitism events, they may recognize and reject foreign eggs more readily than parents who did not. We found that, after being flushed, female blackbirds, Turdus merula, remained close to their nests. Flushed females were more likely to eject foreign eggs and did so more quickly than females that …
Host Responses To Interspecific Brood Parasitism: A By-Product Of Adaptations To Conspecific Parasitism?, Peter Samas, Mark E. Hauber, Phillip Cassey, Tomáš Grim
Host Responses To Interspecific Brood Parasitism: A By-Product Of Adaptations To Conspecific Parasitism?, Peter Samas, Mark E. Hauber, Phillip Cassey, Tomáš Grim
Publications and Research
Background: Why have birds evolved the ability to reject eggs? Typically, foreign egg discrimination is interpreted as evidence that interspecific brood parasitism (IP) has selected for the host’s ability to recognize and eliminate foreign eggs. Fewer studies explore the alternative hypothesis that rejection of interspecific eggs is a by-product of host defenses, evolved against conspecific parasitism (CP). We performed a large scale study with replication across taxa (two congeneric Turdus thrushes), space (populations), time (breeding seasons), and treatments (three types of experimental eggs), using a consistent design of egg rejection experiments (n = 1057 nests; including controls), in areas with …