Sex drives intraspecific scaling of home range size in mammals

Animal home range sizes (HR) are fundamental ecological measures, encompassing the area necessary for an organism to obtain food and nonfood resources needed for survival and reproduction. Understanding variation in HR provides important insights into underlying ecological processes driving space use, contributing to species management and conservation. HR is widely known to increase allometrically at an interspecific level. However, it remains unclear whether the interspecific allometric scaling of mammals’ HR can also be consistently observed within species. Additionally, the influence of sex-specific metabolic and behavioral patterns on intraspecific variation in both HR and HR scaling is not well understood. To address this knowledge gap, we GPS-tracked 475 individuals across Brazil, encompassing 18 mammal species. We estimated individuals’ HR and modeled intraspecific variation in HR against body mass and sex, while controlling for habitat quality and phylogenetic relationships. Males used larger areas and displayed steeper HR scaling than females. While males showed a positive allometric scaling similar to interspecific findings reported in the literature (exponent = 1.23), females’ body mass had no statistically discernible effect on HR. Our findings suggest that sex-related metabolic and behavioral traits influence space use across mammals. In general, males have greater energetic and evolutionary incentives to expand their HR with increasing BM, as well as more physical capacity to do so, compared to females. We highlight that traditional studies on HR and, especially, HR scaling that disregard individual sex may, in reality, reflect an average of two distinct patterns, while failing to accurately represent either one.