Infanticide and social change in two groups of the hanuman langur,Presbytis entellus,at Jodhpur

Infanticide and social change in two neighbouring bisexual groups of the langur,Presbytis entellus, at Jodhpur (at the eastern edge of the Great Indian Desert), during a two-year period are described. Here the fluidity of leadership is more marked than in other primates. The change of leadership is sometimes associated with infanticide. Other features noted were: that neighbouring bisexual groups may temporarily fuse into one; and that intergroup presentations and copulations may occur.