Bonobo

Bonobos, alongside spotted hyenas, demonstrate that female social dominance can evolve in mammals despite typical male size advantage. Female bonobos dominate through coalitions—unrelated females support each other against males, creating collective female power that individual females couldn't achieve alone.

Female coalitions form between non-relatives. Unlike matrilineal systems where female power derives from family, bonobo female coalitions form between immigrants. Females leave natal communities and must build coalitions from scratch in new communities. This non-kin coalition building is rare and suggests strong selection for female cooperation.

Sexual behavior reinforces female bonds. Female-female genital contact ('GG-rubbing') reduces tension and reinforces coalition bonds. This sexual behavior serves social rather than reproductive functions—building the trust and affiliation that coalition support requires.

Male rank depends on mothers. Unlike chimpanzees where males form their own hierarchies, bonobo males derive rank from their mothers' positions. A son of a high-ranking female ranks above a son of a low-ranking female. Male success flows through maternal connection.

For organizations, bonobos demonstrate that female coalitions can reshape power structures. When women actively support each other against male dominance attempts, the resulting female power exceeds what any individual woman could achieve.