Hierarchical Relations Among Female Hanuman Langurs (Primates: Colobinae, Presbytis entellus).

Female hierarchies are stable over short periods but fluctuate from year to year. In general, young females rise in rank over older and often larger female relatives, even though old females remain active in troop defense. This previously undescribed dominance system can be plausibly explained with reference to inclusive fitness theory and the concept of reproductive value.