Testosterone and Heterospecific Aggression in the Adult Eastern Bluebird (Sialia sialis) During the Nestling Period
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چکیده
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]. In male birds the steroid hormone testosterone, mediates territorial aggression [2]. Testosterone and aggression has been studied relative to seasonal cycles [3] and population density Beletsky et al. [4]. Species differences in testosterone and aggression may influence their dispersal ability [5] and geographic distributions [6]. Aggression towards conspecifics and heterospecifics may be mediated by the same physiological pathways and we test this hypothesis here.
منابع مشابه
Alternative Material Nest Boxes and Impacts on Nestling Physiology and Adult Behavior in the Eastern Bluebird (Sialia sialis)
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