A disparity between locomotor economy and territory holding ability in male house mice

Both economical locomotion and physical fighting are important performance traits to many species because of their direct influence on components of Darwinian fitness. Locomotion represents a substantial portion of the total daily energy budget of many animals. Fighting performance often determines individual reproductive fitness through the means of resource control, social dominance, and access to mates. However, phenotypic traits that improve either locomotor economy or fighting ability may diminish performance in the other. Here we test for a predicted disparity between locomotor economy and competitive ability in wild-derived house mice (Mus musculus). We used 8-week social competition trials in semi-natural enclosures to directly measure male competitive ability through territorial control and female occupancy within territories. We also measured oxygen consumption during locomotion for each mouse using running trials in an enclosed treadmill and open-flow respirometry. Our result...