Roberto Refinetti recently published a study titled “Exploring determinants of behavioral chronotype in a diurnal-rodent model of human physiology” in the journal Physiology and Behavior.
An excerpt from the abstract reads, “Basic research on circadian rhythms has provided a basis for investigating the causes of chronotype variation, but experimental tests of pertinent hypotheses are difficult to conduct with human subjects. This limitation can be overcome by use of animal models. This study was conducted with a rodent species, the antelope ground squirrel (Ammospermophilus leucurus), that, like humans, is active during the daytime, exhibits a spread of chronotypes, and has a similar average free-running circadian period.”