Sexually dimorphic oxytocin circuits drive intragroup social conflict and aggression in wild house mice.

In nature, both males and females engage in competitive aggressive interactions to resolve social conflicts, yet the behavioral principles guiding such interactions and their underlying neural mechanisms remain poorly understood. Through circuit manipulations in wild mice, we unveil oxytocin-expressing (OT) neurons in the hypothalamic paraventricular nucleus (PVN) as a neural hub governing behavior in dyadic and intragroup social conflicts, influencing the degree of behavioral sexual dimorphism. We demonstrate that OT PVN neurons are essential and sufficient in promoting aggression and dominance hierarchies, predominantly in females.