Meeting Abstract

92.4  Thursday, Jan. 7   Hormonal responses to calls warning of predators and development of survival behaviors MATEO, J.M.; Univ. of Chicago jmateo@uchicago.edu

Shortly after emerging from natal burrows at one month of age, juvenile Belding’s ground squirrels (Spermophilus beldingi) learn to respond to whistle and trill alarm calls, which warn of aerial and terrestrial predators, respectively. In a variety of vertebrates, exposure to a predator, its cues, or calls warning of it can lead to physiological reactions such as metabolic adjustments, cardiovascular changes, or glucocorticoid release, suggesting that predator contexts are arousing. Increased arousal after hearing an alarm call, coupled with watching the responses it elicited in others, may facilitate juveniles’ acquisition of an association between calls and behavioral responses. Such rapid learning would be adaptive for vulnerable prey animals. I examined experimentally whether young juveniles exhibit differential acute cortisol responses to alarm and non-alarm calls, which would facilitate differential attention to the calls, and perhaps promote rapid learning of the appropriate responses. Cortisol responses to playbacks of whistles, trills, squeals (a conspecific control vocalization) and silent controls were compared within individuals across call types. Results are discussed in terms of physiological and ecological correlates of attention and learning, as well as the general role of glucocorticoids in the development of survival behaviors.