Description
The social decision-making brain network controls social behaviour, including aggression, in a variety of species. However, whether the social decision-making network is conserved in naked mole-rats has yet to be systematically investigated. Naked mole-rats are eusocial rodents that live in large colonies of family groups. The non-breeding subordinates maintain and defend the colony. However, upon encountering intruding conspecifics from another colony, only some resident naked mole-rats will initiate extreme aggression towards the intruder, and others will behave peacefully. These individuals are often called soldiers and workers, respectively. Here we aim to take advantage of this natural stable variation between soldiers and workers to probe for the neurobiological mechanisms of xenophobic aggression in naked mole-rats. We staged interactions between focal soldier and worker naked mole-rats and non-aggressive stimulus animals that were either a stranger or a colony-mate, video-recorded the interactions, and processed the brains for c-fos as a proxy for neural activity. The study is still in progress, but we predict that compared to workers, soldiers interacting with strangers will show higher coordination in activity throughout the social decision-making network, especially in the core aggression network, since their aggression is sustained and intense. Conversely, we predict no difference in activation patterns between soldiers and workers when they interact with a familiar colony-mate. This study will serve as the foundation for further investigations into mechanisms driving xenophobic aggression in naked mole-rats.
