Rhesus macaque Rhesus macaque The rhesus macaque ("Macaca mulatta") is one of the best-known species of Old World monkeys. It is listed as Least Concern in the IUCN Red List of Threatened Species in view of its wide distribution, presumed large population, and its tolerance of a broad range of habitats. Native to South, Central, and Southeast Asia, rhesus macaque have the widest geographic ranges of any nonhuman primate, occupying a great diversity of altitudes and a great variety of habitats, from grasslands to arid and forested areas, but also close to human settlements. The rhesus macaque is brown or grey in
Celebes crested macaque at the top of the head are remarkable features. It has an "apelike" appearance due to its almost non-existent, non-visible, vestigial tail stub of only approximately . With a total body length of to and a weight of to , it is one of the smaller macaque species. Its life expectancy is estimated at approximately 20 years in the wild. The Celebes crested macaque is a diurnal rain forest dweller. This macaque is primarily terrestrial, spending more than 60% of its day on the ground foraging for food and socializing, while sleeping and searching for food in the trees. The