Like chimps, females are around two thirds the size of males and also migrate from their birth group. Their social lives could not be more different, however. Instead of living out their adulthood as a forlorn diaspora with little or no agency, females join groups and form alliances with unrelated females. The power of this constructed sisterhood allows them to dominate the bigger males. It is formed and maintained not by fighting and physical intimidation, but by what scientists describe as G-G rubbing, shorthand for genito-genital rubbing.
