#bearded primates

Long-tailed macaques live in multi-male groups consisting of about thirty members. At sexual maturity, males leave their natal group, and join either bachelor groups or new social groups. Since males leave the natal group, they are subject to more predation, disease, and injury than are females. Within groups, a strict linear dominance hierarchy develops among males. This hierarchy is determined by such factors as age, size, and fighting skills. Since females do not disperse, they are the stable core of a group. Females have a tendency to have close bonds with their maternal relatives throughout their lives. There is, however, a dominance hierarchy among females in a group. The acquisition of rank involves active intervention by maternal kin, and the differential treatment by unrelated members of the group.

Long-tailed macaques are omnivores, and exploit many different food types, reflecting the diversity of habitats they can utilize. They eat a wide variety of foods such as fruits, crabs, flowers, insects, leaves, fungi, grasses, and clay (possibly for potassium). Long-tailed macaques are "ecologically diverse." Some of the habitats in which they have been found are primary forests, disturbed and secondary forests, and riverine and coastal forests of nipa palm and mangrove. Of the various habitats occupied by long-tailed macaques, the swamp forests seem to have the highest density of them.

The roloway monkey is distinguished by its lengthy beard and broad diadem-like browband. Its face and much of its fur are black. It has a white beard, chest, and throat; there are a white stripe along each thigh and a deep reddish or orange patch on its back. 

Roloway monkeys dwell in the canopies of jungles and rainforests where they reside and sleep in the branches of primeval trees. They are typically diurnal and sleep throughout the night. The species is arboreal, and forms social groups of 15 to 30 individuals, typically with 1 male, around 10 females, and their offspring. It is commonplace for the males of groups of roloway monkeys to head off elsewhere on their own, whereas the females will stay with the same group they were born into.

The Emperor Tamarin lives in the southwest Amazon Basin, in east Peru, north Bolivia and in the west Brazilian states of Acre and Amazonas. They are very small, compared to most other primates. Using their claws, they cling to tree branches, maintaining a consistent verticality in the jungle environment. To navigate their lush environment, which typically is in rainforests, they leap and move quickly through trees, rarely touching the forest floor. 

The red-shanked douc is distinguished by its bright maroon/red "stockings" which run from its knees to its ankles. Otherwise it is similar in appearance to the grey-shanked douc, with a golden face, white chin and dark grey to black hands and feet. The black-shanked douc has a largely greyish blue face. The tail of all 3 species is as long as the body. The grey-shanked douc langur is critically endangered with a population estimated to be around 550-700, The red-shanked douc langur and the black-shanked langur are both endangered. Populations of all 3 species have declined by 50-80% over the last 30 years.

The main threats to all 3 species of douc langurs are habitat loss and hunting. The forests on which douc langurs depend are disappearing at an exponential rate as logging and agricultural conversion continues. They are hunted for bush meat and for traditional medicine purposes. Their bones are used to make a substance called "monkey bone balm" which is thought to improve hemoglobin regeneration and renal function. Doucs are also used in the exotic wild life trade. The adults are killed and the infants are taken and sold as pets.