Colony genetic structure of the ant Camponotus ocreatus (Hymenoptera: Formicidae)

An increasing number of studies have uncovered evidence of polygyny or polyandry in the ant genus Camponotus. To further increase our understanding of the sociobiology of ants in this genus, we used DNA microsatellite markers to analyze the genetic structure of C. ocreatus. We found that the genotypes of workers, gynes, and males in 15 of the 16 nests analyzed were consistent with having been produced by a single, once-mated queen. However, nestmate genotypes in one nest were more complex, signifying the presence of multiple reproductives. In addition, the adjusted estimate of diploid nestmate relatedness, r = 0.65, suggested infrequent polygyny or queen polyandry. We also uncovered some evidence of inbreeding between queens and their male mates, and occasional polydomy in this population. Overall our results indicate that the social structure of most C. ocreatus colonies is relatively simple, although the genetic structure of a few colonies suggests that more than a single queen and male may contribute to offspring production.