Dispersal patterns exhibited by group-living animals play an important role in individual reproductive success and survival,as well as population and social dynamics(Greenwood,1980;Isbell and van Vuren,1996;Kappeler and van Schaik,2002).Dispersing individuals may emigrate voluntarily,or they may be forcibly evicted by other individuals(Pusey and Packer,1987;Clobert et al.,2001).One cause of individual dispersal is when an extra-group male compels another male to leave a group of females.This phenomenon has been well documented in primates,especially Old World monkey species(e.g.Colobus vellerosus:Saj and Sicotte,2005;Erythrocebus patas:Ohsawa,2003;Macaca fascicularis:van Noordwijk and van Schaik,2001).
Although there are some reports that have described primates eating animals,it is unknown whether predation on vertebrates exists in herbivorous leaf-eating primates.We have witnessed firsthand wild Sichuan snub-nosed monkeys(Rhinopithecus roxellana)preying on and consuming Eurasian blackbirds(Turdus merula)in the Qinling Mountains of China.This event suggests that R.roxellana,which has previously been described as a herbivorous leaf-eating primate,may be partially carnivorous and the correct classification of this species would be omnivorous.Furthermore,food-share behavior among higher-ranked members occurs in a one-male unit when vertebrate prey is hunted by this species.
