Patterns of buzz running, a pre-swarming behavior, in the Neotropical wasp Parachartergus colobopterus

Knowing whether workers or queens control reproduction is vital for understanding social evolution in insects. Among epiponine wasps, a significant part of reproduction is the production of daughter swarms. One of the first behaviors indicative of swarming is the buzzing run - a behavior in which a wasp runs rapidly back and forth on the natal nest, bumping into nestmates while traversing a significant portion of the nest. In this study we investigated whether the buzz runners in Parachartergus colobopterus were queens who were not reproducing on the current nest (reproductive losers), or workers, as evidence from other species indicates. We suspected that loser queens, who may be anxious to swarm in order to increase reproductive output, could be the buzz runners because P. colobopterus swarms are primarily composed of queens who are not the mothers of the accompanying workers. Our results show that workers are the buzz runners, and that queen number does not influence the level of buzz running on a colony. We also found that buzz running is more common on large colonies with low worker relatedness, the sort that are likely to produce swarms. However, buzzing runs also occurred sporadically on smaller nests. The small nests had more nest parasites (mostly flies) than the large nests, and the parasite dance, which is very similar to the buzzing run, was seen only on these nests.