Energetic constraints on mammalian home‐range size

The metabolic theory of ecology predicts that rates of metabolic processes play a central role in constraining important fitness traits such as home‐range size. Locomotory behaviours are physiologically expensive, yet the relative importance of the animal's energetics in determining their home ranges is unknown. It is tested here whether maintenance costs (BMR; basal metabolic rate), energetic capacity (VO2max; maximum metabolic rate) or available energy above self‐maintenance (aerobic scope) are related to the size of mammalian home ranges using phylogenetic comparative methods. The first quantitative support for the hypothesis that home‐range size is limited by metabolic rates, accounting for variation in body mass, is presented. In particular, the negative effect of BMR, along with the positive effect of VO2max, on home‐range size revealed that aerobic scope plays a prominent role in constraining home ranges. These findings suggest optimization of energy allocation where past selection promoted an increase in mobility at the lowest possible body maintenance costs. High aerobic capacity is needed to operate large home ranges. However, in habitats of limited productivity, the associated increase in self‐maintenance constrains energy allocation to locomotory behaviours, reinforcing the importance of metabolic processes in ecology. A free Plain Language Summary can be found within the Supporting Information of this article. A free Plain Language Summary can be found within the Supporting Information of this article.