SOCIAL INTERACTIONS AND BEHAVIORAL CONTEXT IN A LARGELY SOLITARY BEE,LASIOGLOSSUM (DIALICTUS) FIGUERESI (HYMENOPTERA, HALICTIDAE)

Understanding the development of behavioral differences among group me mbers is a key to understanding social evolution or its loss. Social s weat bees (Halictinae) show distinct behaviors related to social compe tition and cooperation, and the frequencies of these behaviors differ for different functional groups (workers, guards, queens). These behav iors occur in solitary halictine bees under artificial conditions in a circular arena involving pairs of interacting bees. Reproductively ac tive bees were tested, as were reproductively inactive bees, both from different nests and the same nests within a nesting aggregation. Amon g reproductively active bees, the first bee to display aggressive beha vior more frequently had larger ovaries, and the first bee to withdraw from a social encounter more frequently had smaller ovaries. Body siz e did not influence these outcomes. The first bee placed in the arena was more likely to adopt an aggressive posture when bees first met, an d the second bee placed in the arena was more likely to withdraw. Amon g reproductively inactive bees. females paired with a bee taken from t he same nest were less likely to be aggressive than a bee paired with one from a different nest, suggesting familiarity (possibly kinship) c an modulate aggressive behavior.