Phylogenetics of allodapine bees: a review of social evolution, parasitism and biogeography

It has been assumed that allodapine bees represent early stages in the evolution of social behaviour. Early studies suggested that sociality evolved from solitary forms, and that the solitary to social transition coincided with a transition from mass to progressive provisioning of brood. Recent studies challenge both of these assumptions, they suggest that: (i) Macrogalea replaces Halterapis + Compsomelissa as the sister group to all other genera; (ii) sociality is plesiomorphic for the tribe; and based on extended Halterapis research, (iii) there are no strictly solitary allodapine species and, therefore, no reversals to solitary living. Penalised likelihood dating of Bayesian inferred phylograms show allodapine lineages have an origin older than 40 Mya. The early origin of sociality in this tribe may explain the diverse array of social organization (and social parasitism) found in species across a range of clades, and the age of the group raises curious biogeographic scenarios.