Multiple origins of advanced eusociality in bees inferred from mitochondrial DNA sequences.

The remarkably high level of colony organization found in the honey bees and stingless bees (family Apidae) is extremely rare among animals. Yet there is controversy over whether these two groups independently evolved advanced eusocial behavior or inherited it from a common ancestor. Phylogenetic analyses of DNA sequence information from the mitochondrial genome (large-subunit ribosomal RNA gene) of representative apid bees suggest that advanced eusocial behavior evolved twice independently within this assemblage. These results depart from previous hypotheses of apid relationships by indicating a close phylogenetic relationship between the primitively eusocial bumble bees and the stingless bees.