Southern pig-tailed macaque to harvest coconuts. This macaque is mostly found in rainforest up to 2000 meters, but will also enter plantations and gardens. It is found in the southern half of the Malay Peninsula (only just extending into southernmost Thailand), Borneo, Sumatra and Bangka Island. There are reports of the species having been present in Singapore before 1950, but these were likely escaped pets. The only pig-tailed macaques in Singapore today are introduced monkeys. Southern pig-tailed macaque The southern pig-tailed macaque ("Macaca nemestrina"), also known as the Sundaland pigtail macaque and Sunda pig-tailed macaque, is a medium-sized macaque that lives in southern
Rhesus macaque between the central and peripheral males. A subgroup of subordinate, often subadult, males occupy the very edge of the groups, and have the responsibility of communicating with other macaque groups and making alarm calls. Rhesus social behaviour has been described as despotic, in that high-ranking individuals show little tolerance and frequent and often severe aggression towards non-kin. Rhesus macaques interact using a variety of facial expressions, vocalizations, body postures, and gestures. Perhaps the most common facial expression the macaque makes is the "silent bared teeth" face. This is made between individuals of different social ranks, with the lower-ranking one giving