Tolerância entre operárias de Polybia paulista (Hymenoptera: Vespidae): Agressividade e sinais cuticulares ao longo do espaço

Abstract

Social insects primarily rely on chemical cues for the recognition of nestmates and non-nestmates. This mechanism remains poorly understood in swarm-founding social wasps, such as species of the genus Polybia. Therefore, this study evaluated whether the distance between colonies affects aggressiveness among workers of Polybia paulista when encountering each other at carbohydrate sources, and whether these interactions are related to differences in cuticular hydrocarbon (CHC) profiles. We hypothesized that workers from more distant colonies would exhibit greater divergence in CHC profiles and, consequently, higher levels of aggressiveness. Behavioral interactions were evaluated among workers of P. paulista from four colonies, including interactions between workers from the same colony (control), from nearby colonies (≤ 5 km), and from distant colonies (> 5 km). The same workers used in the behavioral assays subsequently had their cuticular hydrocarbons extracted and analyzed by gas chromatography coupled with mass spectrometry. Aggressive behavior was recorded in only 6% of the tests, and binomial logistic regression indicated no significant differences among treatments (p > 0.05). Linear Discriminant Analysis showed that the chemical profiles of the colonies were highly similar, as evidenced by the overlap of CHC profiles among workers from the four colonies, preventing their discrimination based on chemical cues. In all colonies, alkenes predominated, particularly heptacosene, nonacosene, and pentacosene. These results suggest that spatial distance does not affect aggressiveness among P. paulistaworkers during the exploitation of carbohydrate-rich resources, possibly because carbohydrates are poorly defensible resources and because of the high similarity in CHC profiles among colonies. Consequently, P. paulista exhibits low aggressiveness during interactions at food resources, favoring the coexistence of multiple colonies in shared environments.