The white-cheeked spider monkey, Ateles marginatus, is a species of spider monkey

Spider monkey

Spider monkeys of the genus Ateles are New World monkeys in the subfamily Atelinae, family Atelidae. Like other atelines, they are found in tropical forests of Central and South America, from southern Mexico to Brazil...

, a type of New World monkey

New World monkey

New World monkeys are the five families of primates that are found in Central and South America: Callitrichidae, Cebidae, Aotidae, Pitheciidae, and Atelidae. The five families are ranked together as the Platyrrhini parvorder and the Ceboidea superfamily, which are essentially synonymous since...

, endemic

Endemic (ecology)

Endemism is the ecological state of being unique to a defined geographic location, such as an island, nation or other defined zone, or habitat type; organisms that are indigenous to a place are not endemic to it if they are also found elsewhere. For example, all species of lemur are endemic to the...

 to Brazil

Brazil

Brazil , officially the Federative Republic of Brazil , is the largest country in South America. It is the world's fifth largest country, both by geographical area and by population with over 192 million people...

.

There are many different varieties of spider monkeys that make their home in the upper levels of the rain forest. The white-cheeked spider monkey was placed on the endangered species list after an assessment in 2008 discovered that their population had decreased by 50% over the course of three generations; this decline can be attributed to habitat loss and hunting. This trend is expected to continue due to the increasing expansion of soybean

Soybean

The soybean or soya bean is a species of legume native to East Asia, widely grown for its edible bean which has numerous uses...

 agriculture. Also, parts of their habitat have been destroyed to make way for major highways and extensive deforestation. The white-cheeked spider monkey is commonly found in the Brazilian Amazon. The area it is most likely to be found in resides between the Rio Tapajós (right bank) and its tributary, the Rio Teles Pires (right bank) and the Rio Xingu (left bank), south of the Rio Amazonas. A portion of their territory lies also within national forests such as Tapajós National Forest (545000 ha (1,346,723.1 acre)), Xingu National Forest (252790 ha (624,657.1 acre)), Alatmira National Forest (689012 ha (1,702,584.2 acre)), Itaituba I National Forest (220034 ha (543,715.4 acre)), and Itaituba II National Forest (440500 ha (1,088,498.2 acre)).

Some of the indigenous peoples in Brazil

Indigenous peoples in Brazil

The Indigenous peoples in Brazil comprise a large number of distinct ethnic groups who inhabited the country prior to the European invasion around 1500...

 consider spider monkeys a delicacy, and when this is combined with their low reproduction rate, the population is sure to decline swiftly. It generally lives in groups of 20-30 individuals, but it is rare for them to be seen all together. It is more common for the white-cheeked spider monkey to travel in smaller groups of 2-4 when feeding and resting. At around 4–5 years of age, it apparently reaches sexual maturity and will give birth to one offspring after a gestation period of 226–232 days; the interbirth interval can last as long as 28–30 months in the wild.

The diet of the white-cheeked spider monkey consists of fruit, leaves, flowers, aerial root

Aerial root

Aerial roots are roots above the ground. They are almost always adventitious. They are found in diverse plant species, including epiphytes such as orchids, tropical coastal swamp trees such as mangroves, the resourceful banyan trees, the warm-temperate rainforest rātā and pōhutukawa Aerial roots...

s, bark, decaying wood, honey, and even some small insects such as termite

Termite

Termites are a group of eusocial insects that, until recently, were classified at the taxonomic rank of order Isoptera , but are now accepted as the epifamily Termitoidae, of the cockroach order Blattodea...

s and caterpillar

Caterpillar

Caterpillars are the larval form of members of the order Lepidoptera . They are mostly herbivorous in food habit, although some species are insectivorous. Caterpillars are voracious feeders and many of them are considered to be pests in agriculture...

s. One very important impact it has on its habitat is to provide seed dispersal

Seed dispersal

Seed dispersal is the movement or transport of seeds away from the parent plant. Plants have limited mobility and consequently rely upon a variety of dispersal vectors to transport their propagules, including both abiotic and biotic vectors. Seeds can be dispersed away from the parent plant...

for different species of plants throughout their territory, it is thought that they provide movement for 138 different species of fruit seeds.