Many animal societies rely on division of labor, but how such roles emerge and become stable is still poorly understood. In small groups of genetically identical mice living together in home-cage, individuals spontaneously adopt different roles—some work to access food, others rely on them to feed. These behavioral profiles are not fixed: they depend on the social context. Male groups tend to form competitive hierarchies, female groups behave more uniformly, and introducing trained or dopamine-modulated individuals into naïve groups reshapes group organization.
These roles are linked to activity in a key brain area for motivation—the ventral tegmental area—and modeled using reinforcement learning principles. Altogether, the results suggest a feedback loop where social interactions influence brain activity, which in turn stabilizes individual behaviors and group structure.
Keywords: Social behavior, microsociety, dopamine, specialization
This part of the website could either be in French or English, depending on the sources of the actualities.