This is a problem of sexual selection. Compare them among separate zoogeographic realms. Consider the prediction that all mammals larger than 25 kg adult weight will be extirpated in the wild by man in the next century. Do mammalian activity patterns reflect resource maximizing or risk aversion strategies. Discuss this in relation to home range.
Animals seek resources and avoid predators, parasites and intraspecific enemies.
For example, little mammals, like mice, have little home ranges compared to elephants. Test an hypothesis. No one has ever followed up on this claim. Don't do this question. Recently, in the journal, Animal Behaviour , there have been several articles on sperm competition in relation to the functions of masturbation and female orgasm, all from the perspective of natural selection of course.