The Nilgiri Langur (Presbytis Johnii) Troop: its Composition, Structure, Function and Change

Adult Male Replacement in One-Male Troops of Purple-Faced Langurs (Presbytis senex senex) and its Effect on Population Structure

“…At Horton Plains, all reproduc tively active troops contained only a single adult male. The one-male troop organisation characteristic of P. senex is similar in structure to the one-male troops reported for the south Indian gray langur [Sugiyama, 1964], the Nilgiri langur, P.jolmii [Poirier, 1969], the black and white colobus, Colobus guereza [M arler, 1969], and the patas monkey, Erythrocebus patas [Hall, 1968], but different from the one-male units described for the hamadryas ba boon [K ummer and K urt, 1963], the gelada [Crook, 1966], or the family groupings of the gibbon [Carpenter, 1963;E llefson, 1968].…”

“…It was clear that this social grouping was reproductively inac tive, since adult females or infants were not found within it. This type of troop structure has not been reported in any of the previous studies, although all male bands have been described in several primate societies [Sugiyama, 1964;J ay, 1965;C rook, 1966;H all, 1968;K ummer, 1968;Poirier, 1969;.…”

Female Dominance in Indri indri

“…In the case of adult males and adult females the frequent observations of males' priority of access to resources over females require some explanation. Consistent adult male dominance over adult females during aggressive interactions have been reported for many primate species such as Macaca irus [Shirek-Ellefson, 1967], Macaca fascicularis [Angst, 1975], captive Cercocebus albigena [Chalmers and Rowell, 1971], Cercopithecus aethiops [Struhsaker, 1967], Presbytis johnii [Poirier, 1969], Ateles geoffroyi [Rondinelli and Klein, 1976], Pan troglodytes [Goodall, 1965;Nishida, 1970] and Gorilla gorilla [Schaller, 1963]. Furthermore, adult male dominance over females is an intrinsic part of the social organisation of some species char acterised by harem formation where males discipline females in order to obtain and maintain an integral group [e.g.…”

Observations on the Inter-Troop Movement of Adult Vervet Monkeys (Cercopithecus aethiops)

“…Migration, either in the form of arrival into, or departure from a social unit, or in the presence of extra-group animals has now been noted in a wide variety of species and genera [Baldwin, 1969;Struhsaker, 1967;Poirier, 1969;Lindburg, 1969;Rudran, 1973;Dittus, 1975;Dunbar and Dunbar, 1975;Hausfater, 1975;Harcourt et ah, 1976;Sugiyama, 1976]. The apparent ubiquity of the process indicates that it should be regarded as a fundamental feature of social organization and not as an anomaly or curiosity [Slatkin and Hausfater, 1976].…”