Breeding density, not life history, predicts interpopulation differences in territorial aggression in a passerine bird
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Testosterone and Heterospecific Aggression in the Adult Eastern Bluebird (Sialia sialis) During the Nestling Period
During the breeding season, birds establish territories and aggressively defend them against intruders. In general, conspecific intruders elicit greater behavioral responses than heterospecific because heterospecifics are not usually competing for the same resources. Interference competition, through aggressive interactions between species, has the potential to affect community structure [1]. I...
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The importance of behaviours as instigators or inhibitors of evolutionary change remains largely unresolved and this is in part because there are very few empirical examples of how behaviours affect evolutionary processes. By determining the environment of breeding, aggressive interactions over territories have the potential to strongly impact selection pressures experienced by individuals. Wes...
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