Two paradigms of population regulation

No population increases without limit and ecologists have utilised two paradigms to find out why. The density-dependent paradigm assumes that birth, death and movement rates will be related to population density. In many cases they are not, and the search for density dependence has become a holy grail. A better approach is through the mechanistic paradigm which searches for relationships between birth, death and movement rates, and the mechanisms controlling populations, such as disease, predation, food shortage and territoriality. Seven suggestions are made for analysing the role of disease in population regulation in mammals. Useful progress will flow more quickly from the mechanistic paradigm without the need to search for density dependence.