Cooperative breeding in mammals.

Cooperative breeding in mammals covers a diversity of breeding systems. In all cases, however, Individuals assist in the rearing of offspring other than their own. Recent research has highlighted some of the factors responsible for variation both within and between species. While it is possible to generalize about the selective pressures leading to cooperative breeding, doing so may obscure important contrasts between taxa. Of course, inclusive-fitness models explain the generalities of cooperative breeding, but differences in ecology, physiology and life history may result in distinctive processes operating in different taxa-data only likely to emerge from long-term field studies.