Task group differences in cuticular lipids in the honey bee Apis mellifera

Abstract

Social insects are defined by their ability to divide labor among their numerous nestmates. This is achieved via a complex system of chemical communication that allows colonies to organize task activity so as to maximize the productivity of the colony. However, the mechanism by which social insects distinguish task groups among morphologically identical individuals remains unknown. Using the honey bee, Apis mellifera, as our model species, we investigated the presence of task-specific patterns in the cuticular lipids (n-alkanes, fatty acids, and alkenes) of bees. Cuticular lipids are known to play an essential role in the recognition processes of insects. We found task-specific features in the n-alkane and alkene profiles of bees, but no task-specific patterns in the fatty acid profile. Foragers, in particular, had elevated levels of n-alkanes relative to nurse and newly emerged bees, suggesting increased waterproofing. Newly emerged bees had low levels of cuticular lipids, supporting the Blank Slate theory and potentially explaining their acceptance into foreign colonies.