Meeting Abstract

P3.183  Sunday, Jan. 6  Defense behavior and the stress response in three species of python BRASHEARS, J.A.*; FOKIDIS, H.B.; DENARDO, D.F.; Colgate University; University of British Colombia; Arizona State University jbrashears@colgate.edu

Previous research has focused on correlating an animal’s type of defense behavior with its stress response. Proactive defense behaviors (fighting or fleeing)have been associated with high baseline plasma glucocorticoid concentrations and low hormone stress responses, while reactive defense behaviors (freezing or hiding) have been associated with high hormone stress responses. This paradigm has been fruitful in understanding the behavior of many organisms, particularly mammals and birds, but it is unknown how broadly this paradigm can be extended to other taxa. We tested the relationship between defense behavior and the stress response in three species of python (Antaresia childreni, Python regius, Bothrochilus boa) with qualitatively different defense behaviors. We measured defense behavior both pre- and post-stressing, and compared the results to plasma corticosterone concentrations. We also measured maximum corticosterone production in each species using intracardiac injection of adrenocorticopric hormone (ACTH). Contrary to our predictions, we found that species with proactive defense behavior had a higher hormone stress response than the species with reactive defense behavior. Although the most aggressive species, B. boa, has high baseline levels of corticosterone, they were not high in the other proactive species, A. childreni. We conclude that the proactive/reactive dichotomy may not be sufficient to explain the relationship between the stress response and defense behavior in pythons and that further research in this area should focus on identifying broad trends across diverse species.