Meeting Abstract

27.8  Friday, Jan. 4  How do hormones, performance, sexual signals, and behavior interact to predict dominance in brown anoles? MINER, S.V.*; MEYERS, J.J.; HUSAK, J.F.; IRSCHICK, D.J.; Univ. of Massachusetts, Amherst; Univ. of Massachusetts, Amherst; Univ. of Massachusetts, Amherst; Univ. of Massachusetts, Amherst simon@bittennails.com

Males of many species utilize elaborate secondary sex characteristics and behaviors to compete with rivals and determine dominance relationships important to territory acquisition and access to females. We examined what morphological, behavioral, and hormonal traits are involved in determining the outcome of these intrasexual confrontations. We studied the lizard Anolis sagrei because it is highly territorial and frequently engages in intrasexual confrontations. It possesses an enlarged easily recognizable sexual signal (dewlap) combined with easily quantifiable agonistic behaviors and readily uses its performance capacities during these interactions. Specifically, we investigated possible correlations between display frequency in the wild, sexual signal size (dewlap size), head and limb morphology, two well-studied performance traits that are known to impact dominance relationships (bite force and sprint speed), and circulating testosterone levels. We then staged size-matched encounters in the laboratory to determine which of these traits best predicted dominance. Our integrative dataset combining field display behavior, hormone levels, performance, and dominance will help to foster a better understanding of mechanisms governing the outcome of male-male contests.