Body size variation in mammals and its influence on life history
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The relationship between home range area and body size of terrestrial mammals is reconsidered in light of the concept of biological time. Biological time is an internal, body—mass—dependent, time scale to which the durations (of rates) of biological events are entrained. These events range from purely physiological (e.g., muscle contraction time) to purely ecological (e.g., time to traverse home range). Evidence is presented that home range size scales linearly to body mass for carnivores as it does for herbivores. This scaling supports the hypothesis that animals select their home range areas to meet metabolic demands integrated over biologically critical periods. Confounding variables in the home range—body mass regression include habitat productivity and methods of location. Data on home ranges derived from telemetry studies of terrestrial carnivores are presented and used to derive allometric equations for home range area. The exponents of these equations are shown to approximate 1.0, although intercept values vary with latitude and, presumably, habitat productivity. Social organization and behavior may also influence the relationship of home range area to metabolic needs for different sex and age categories within a species.