The Role of Biogenic Amines in Social Insects: With a Special Focus on Ants

SIMPLE SUMMARY: Insects, such as wasps, ants, and bees, can live in highly structured societies characterized by a complex organization. The functioning of these societies is achieved through the coordination of several individuals who can be involved in various tasks and whose numbers are regulated to respond to the overall colony status or needs. The regulatory mechanisms of social behavior are not fully unraveled, but molecules such as brain biogenic amines likely play a pivotal role. Here, we review the potential function of biogenic amines such as dopamine, tyramine, serotine, and octopamine in modulating insect social behavior, with a particular emphasis on ants. We discuss the aminergic regulation of the reproductive state, locomotory performance, learning processes, memory, aggression, geomagnetic-driven orientation, and hierarchical or interspecific interactions across groups of Hymenoptera. We also conducted a bibliometric analysis to highlight potential trends and research interest in the literature related to biogenic amines and their potential role as social behavioral modulators. Social insects have proved to be perfect models to further delve into the aminergic regulation of the behavior, and biogenic amines seem to be good candidates as pivotal factors promoting the evolution of sociality in insects. ABSTRACT: Eusociality represents the higher degree of interaction in insects. This complex social structure is maintained through a multimodal communication system that allows colony members to be flexible in their responses, fulfilling the overall society’s needs. The colony plasticity is supposedly achieved by combining multiple biochemical pathways through the neuromodulation of molecules such as biogenic amines, but the mechanisms through which these regulatory compounds act are far from being fully disentangled. Here, we review the potential function of major bioamines (dopamine, tyramine, serotine, and octopamine) on the behavioral modulation of principal groups of eusocial Hymenoptera, with a special focus on ants. Because functional roles are species- and context-dependent, identifying a direct causal relationship between a biogenic amine variation and behavioral changes is extremely challenging. We also used a quantitative and qualitative synthesis approach to summarize research trends and interests in the literature related to biogenic amines of social insects. Shedding light on the aminergic regulation of behavioral responses will pave the way for an entirely new approach to understanding the evolution of sociality in insects.