ABSTRACT

The tribe Allodapini (Family Apidae) contains about 200 described species and is largely restricted to sub–Saharan Africa, the Indo–Oriental region and Australia. Although some species exhibit only solitary (subsocial) behavior, most species show at least transient phases of social organization, ranging from prereproductive assemblages to forms of eusociality involving morphologically distinct and sometimes flightless queens. Sociality varies widely between species within genera, between populations within species, and between colonies within populations, providing a wealth of opportunities for comparative approaches to social evolution. We discuss a variety of intrinsic and extrinsic factors that have the potential to influence social evolution. The allodapine trait of communal, progressive rearing of brood could affect social evolution in a variety of ways. Lack of cell partitions means that immatures are largely dependent on the continuing presence of adults for defense against parasites and predators. This may select for cooperative nesting if brood can be defended by one adult while another forages. Rearing of brood in communal chambers could select for kin association among adult females because of the potential for nestmate parasitism and the inability to restrict parental care to a nestmate's own offspring. Progressive rearing of brood creates the potential for egg production to be decoupled from tasks involved in larval rearing, so that specialization in tasks such as guarding, foraging and nursing could develop after reproduction has been completed.