Colobine field researchers, therefore, excel at watching their stationary subjects digest. The more leaves consumed, the more time gut microbes need to process them. One of the most dangerous species to both is a fellow primate: at some sites over 90% of chimpanzees' mammalian diet is red colobus, who may suffer major long-term decline as a result (Lwanga et al. A likely benefit to both colobus and Diana monkeys is mutual predator detection: red colobus, traveling higher in the canopy, are better positioned to detect shared aerial predators, while Diana monkeys sound the alarm (recognized by colobus) for arboreal and terrestrial predators (Fashing 2010). West African olive and red colobus often associate with Diana monkeys ( Cercopithecus diana), a cercopithecine.

Range sizes of many colobines vary seasonally, tracking the proportion of different dietary components. Home ranges of most colobines are small (10 km 2) likely reflect their relatively unproductive montane habitat (Kirkpatrick 2010). A growing appreciation of variability and selectivity in colobine diets has led researchers to recognize that these monkeys compete for food more than had been previously thought (Snaith & Chapman 2007). Many African colobines select leaves high in protein and/or low in fiber (Fashing 2010). Colobines are discriminating leaf-eaters, often preferring certain species and younger leaves with fewer structural and chemical defenses. The winter diet of some mountain-dwelling snub-nosed monkeys is almost exclusively lichen (Kirkpatrick 2010). The proportion of seeds and fruits in the diet can increase seasonally, however, reaching 87% seeds in the maroon leaf monkey ( Presbytis rubicunda Davies 1991). Leaves are a major component of many species' diets, up to 92% in a population of Ugandan red colobus ( Piliocolobus tephrosceles Snaith and Chapman 2008). 1994).Ĭolobines are leaf-eating specialists with high-cusped molars and multi-chambered stomachs housing mutualistic microbes that digest cellulose and detoxify plant defensive compounds. bieti) spend half the year in snow at elevations up to 4700 meters (Figure 2 Long et al. The four snub-nosed monkey species ( Rhinopithecus), also endangered, occupy the most extreme environments - the montane forests of China, Vietnam, and Myanmar, where a new species was recently discovered (Geissman et al. Two other colobine genera, each containing one species, live on Indonesian islands, the endangered proboscis monkey ( Nasalis larvatus) in peat swamps and mangrove forests of Borneo, and the critically endangered pig-tailed langur ( Simias concolor) in the Mentawai island chain. cinerea) critically so (<700 wild individuals, IUCN 2010). Six allopatric taxa in the Trachypithecus Francoisi group, many of which are endangered, live almost exclusively in limestone karst habitat, sleeping in caves and clambering on rocky cliffs.Īll three douc species ( Pygathrix) of Vietnam, Cambodia, and Laos are rare and endangered, the grey-shanked douc ( P. Surilis ( Presbytis) and lutongs ( Trachypithecus) occupy dipterocarp forest and rubber plantations in Indonesia and Malaysia, with Trachypithecus species extending north to China and west to India.

Grey langurs ( Semnopithecus), the most terrestrial colobines, occur throughout western Asia from Sri Lanka to Nepal in habitat ranging from moist, scrub, and conifer forest to gardens and temples. Like their African cousins, most Asian colobines are primarily arboreal, though the forests they inhabit cover a wider range of latitudes and altitudes, from lowland tropical to montane. From Guinea to Ethiopia, the five mostly allopatric black-and-white Colobus species have the broadest distribution and occupy the widest variety of forest habitats. Piliocolobus (red colobus) includes 16 allopatric species, widely distributed from Senegal to Zanzibar many are endangered, and one possibly extinct (IUCN 2010). In the west, the smallest and least-studied genus, Procolobus (olive colobus), has the most restricted range and is represented by a single species. Arboreal colobus are found throughout African forests. Recent classifications propose three African and seven Asian genera (Groves 2005).

Old world vs new world monkeys