Mammal Population Regulation, Keystone Processes And Ecosystem Dynamics, Phil. Tran. Biol. Sc.
The theory of regulation in animal populations is fundamental to understanding the dynamics of populations, the causes of mortality and how natural selection shapes the life history of species. In mammals, the great range in body size allows us to see how allometric relationships affect the mode of regulation. Resource limitation is the fundamental cause of regulation. Top-down limitation through predators is determined by four factors: (i) body size; (ii) the diversity of predators and prey in the system; (iii) whether prey are resident or migratory; and (iv) the presence of alternative prey for predators.