Cooperative breeding in mammals

Abstract

Cooperative behavior between group members is common among mammals living in stable social groups (Dugatkin 1997) but cooperative care of young is less common and varies widely in development between species (Russell 2004). It is useful to distinguish four different types of cooperative breeding. In group breeders, multiple breeding females live and breed in the same social group. Group members may cooperate to defend resources against neighboring groups or to detect or deter predators, but direct alloparental care is limited or uncommon. Societies of this kind are common among macropods, bats and ungulates as well as in some families of primates and carnivores (Bradbury & Vehrencamp 1974a, 1974b, Jarman 1974, Clutton-Brock 1989b). In communal breeders, groups include multiple breeding females who share care of young born in the group. Not all females breed in each reproductive attempt and parents may be assisted by temporarily non-breeding females or by males. Well-studied examples include a number of social carnivores, including African lions, banded mongooses and spotted hyenas (Gittleman 1989, Lewis & Pusey 1997), and some bats also show communal care of offspring (Wilkinson 1987, 1992). In several cercopithecine primates, breeding females belonging to the same matriline cooperate to protect and support each other's offspring and these species, too, should, perhaps, be regarded as communal breeders (see Cheney 1977, 1990, Hrdy 1977, Chapais 1992).