Dominance rank of adult females and mating competition in Sichuan snub-nosed monkeys (Rhinopithecus roxellana) in the Qinling Mountains, China

The dominance hierarchy of the female Yunnan snub-nosed monkeys (Rhinopithecus bieti)

“…Similar results have been found in studies of Pan troglodytes [32,33,34] and R. roxellana [35]. The dominance hierarchy manifests after repeated asymmetric agonistic interactions between individuals, which may be limited to certain contexts that depend on environmental conditions [7].…”

Postconflict Conciliation within One-Male Breeding Units in Sichuan Snub-Nosed Monkeys in the Qinling Mountains, China

“…This might relate to lower social pressure between males and females or among females within an OMU compared with multiple OMUs at the species level. Following conflicts, reconciliation and bystander affiliation occurred frequently, which is beneficial for maintaining strong bonds between individuals and therefore beneficial for group coherence and survival [He et al, 2013]. In addition, the conciliatory tendency in the mating season was not significantly different from that in the nonmating season, which may be related to the the low level of antagonism found in Sichuan snub-nosed monkeys year round .…”

“…The existence of bystander affiliation in R . roxellana may also be due to an appropriate degree of empathy to an opponent's emotional state following aggression, or because the males and females within OMUs are more tolerant towards each other than observed in other primates, particularly other colobines [de Waal and van Roosmalen, 1979;Fraser et al, 2008;He et al, 2013]. However, the same studies but on other species of Rhinopithecus are clearly required to confirm such a hypothesis.…”

“…Unlike other colobines, each OMU female has similar reproductive opportunities in wild R . roxellana , resulting in a low degree of female competition over mating partners [He et al, 2013] and the formation of strong female-female bonds [Ren et al, 1991]. When conflicts occurred between the breeding male and a female, other females within the OMU usually made nonaggressive interventions during the conflict, such as holding the lumbar area, grooming or embracing, in both the mating and nonmating seasons [Ren et al, 1991], which may explain the nonsignificant difference in conciliatory tendency in the mating and nonmating seasons.…”

“…roxellana groups are composed of all-male units and OMUs that consist of a single breeding male, multiple adult females and their offspring. Conflict between the male and females of the same OMU occurs, but the breeding male will often protect and support OMU females during their conflict with other individuals and will have stronger bonds with the females within the OMU than with those not in the OMU [He et al, 2013]. The malefemale relationship is based on the degree of spatial cohesion of the OMU but is affected by friendly contact following conflict [Colmenares, 2004]; thus, it would be interesting to clarify the patterns and unique scenarios that exist in R. roxellana compared with other colobines.…”