Meeting Abstract

S2-2.2  Wednesday, Jan. 4  The relationship between aggressiveness and boldness, tendency to explore and learning performance in Kryptolebias marmoratus: the influence of recent contest experiences and the roles of hormones HSU, Yuying*; CHANG, Ching; National Taiwan Normal University, Taipei, Taiwan; National Taiwan Normal University, Taipei, Taiwan

In some species, correlations have been found between individuals’ aggressiveness and their boldness, their tendency to explore their environment actively or their performance in certain learning tasks. Researchers have suggested that a cause for the correlation between these behaviors might lie in the neuroendocrine system. In this study, we examined the relationships between aggressiveness and each of boldness, tendency to explore and learning performance in a mangrove killifish, Kryptolebias marmoratus. We tested the stability of the relationships by using a winning or losing experience to alter individuals’ aggressiveness. We also explored the possibility that the relationships arise because these behaviors are modulated by common physiological mechanisms (i.e. levels of cortisol and testosterone). The results showed (1) that aggressiveness was positively correlated with boldness but not with tendency to explore or learning performance, (2) that recent contest experience influenced individuals’ aggressiveness, tendency to explore and learning performance but not their boldness, (3) that contest experience did not, however, influence the relationship between aggressiveness and boldness and (4) that both aggressiveness and boldness were positively correlated with an individual’s baseline testosterone level measured prior to its contest experience. The results suggest that there is a stable aggressiveness-boldness syndrome in K. marmoratus and that testosterone might be involved in mediating this.