Affiliative and cooperative relationships are not common among mammalian males. This may be partly the result of sexual selection which favors competitive and agonistic interactions among mature males, and partly the result of the fact that female mammals are generally philopatric. This means that adult males usually live among unrelated and unfamiliar individuals. Bonnet macaques (Macaca radiata) represent one of several exceptions to this general pattern. Adult males in this species frequently sit together, groom, huddle, greet, and support one another. The nature of social relationships among males are related to their participation in coalitions as males tend to support the males with whom they associate and interact affilatively, and intervene against the males with whom they generally exchange greetings and aggression.