Task Allocation in Artificially Induced Colonies of a Basically Solitary Bee Ceratina (Ceratinidia) okinawana, with a Comparison of Sociality between Ceratina and Xylocopa (Hymenoptera, Anthophoridae, Xylocopinae)

Our previous results on the induction of the caste system in 3 basically solitary species of Ceratina (Ceratinidia) bees are reviewed. Semisocial and eusocial colonies of the multivoltine C. okinawana were induced with either kin or non-kin partnership. In eusocial colonies more kin groups were normally eusocial (queen=mother) while more non-kin groups were reversed eusocial (queen=daughter). Otherwise kinship did not much affect the structure of task allocation, which was similar in all social types : The queen functions as principal guard and primary egg layer, while the worker as forager and often as secondary egg layer, who lays egg after eating the partner's egg. Task allocation in Ceratina was regarded as more stable than in Xylocopa. Coaction of kinship and epigenetic factors in social evolution is stressed.