Meeting Abstract

8.5  Wednesday, Jan. 4  Heritability, Size, and Aggression Interact to Influence Social Dominance Ability in Male House Mice CUNNINGHAM, C.B.*; CHASE, K; RUFF, J.S.; EDMUNDS, T.N.; POTTS, W.K.; CARRIER, D.R.; University of Utah

The evolutionary importance of physical conflict to anatomical, behavioral, and life history traits has been recognized since Darwin. Despite the importance of competitive ability to the evolution of many animals, little is known about the traits that interact to determine it. Male house mice (Mus musculus) use agonistic physical competition to establish social dominance relationships. Importantly, this behavior almost completely determines the reproductive fitness of an individual male. In this study, we used recently, wild-derived male house mice to evaluate their ability to gain and hold a preferred territory over multiple days. We estimated the consequences of several factors predicted to influence dominance ability; heritability, size, and aggression. We found that social dominance ability exhibited high narrow-sense heritability, h2 ≈ 0.62. Body mass had a moderate positive influence on social dominance ability; however, small males were still able to succeed. Aggression measured as latency to attack and frequency of attacks during resident-intruder assays was not correlated with dominance ability. These results highlight the lack of understanding of this fundamental behavior and suggest a more complex foundation to dominance ability than is generally assumed to be true.