Wheel-running behavior in 12 species of muroid rodents

The objective of this research was to describe the levels and periodicity of wheel running in 12 species of muroid rodents in order that comparisons could be made among different measures of activity in a variety of species. Six males from each species (Peromyscus polionotus, P. eremicus, P. leucopus, P. maniculatus, P. gossypinus, Microtus pennysylvanicus, M. montanus, M. canicaudus, M. ochrogaster, Calomys callos us, Onychomys leucogaster, and Mus musculus) were tested in running wheels for 14 days, with the amount of running recorded hourly. There were significant species differences in amount of wheel running, with Peromyscus generally running more than Microtus. All species displayed marked nocturnality. Thus, Peromyscus display consistent nocturnality both across species, and for various behavioral patterns measured using a variety of methods. By contrast, Microtus display a nocturnal pattern of wheel running, but not of eating, drinking, and various other behavioral patterns. These differences appear to reflect adaptations related to habit and diet.