The Bornean orangutan (''Pongo pygmaeus'') is a species of
orangutan
Orangutans are great apes native to the rainforests of Indonesia and Malaysia. They are now found only in parts of Borneo and Sumatra, but during the Pleistocene they ranged throughout Southeast Asia and South China. Classified in the genus ...
endemic
Endemism is the state of a species being found in a single defined geographic location, such as an island, state, nation, country or other defined zone; organisms that are indigenous to a place are not endemic to it if they are also found elsew ...
to the island of
Borneo
Borneo (; id, Kalimantan) is the third-largest island in the world and the largest in Asia. At the geographic centre of Maritime Southeast Asia, in relation to major Indonesian islands, it is located north of Java, west of Sulawesi, and eas ...
. Together with the
Sumatran orangutan
The Sumatran orangutan (''Pongo abelii'') is one of the three species of orangutans. Critically Endangered, and found only in the north of the Indonesian island of Sumatra, it is rarer than the Bornean orangutan but more common than the recent ...
(''Pongo abelii'') and
Tapanuli orangutan
The Tapanuli orangutan (''Pongo tapanuliensis'') is a species of orangutan restricted to South Tapanuli in the island of Sumatra in Indonesia. It is one of three known species of orangutan, alongside the Sumatran orangutan (''P. abelii''), found ...
(''Pongo tapanuliensis''), it belongs to the only genus of great apes native to Asia. Like the other great apes, orangutans are highly intelligent, displaying tool use and distinct cultural patterns in the wild. Orangutans share approximately 97% of their DNA with
human
Humans (''Homo sapiens'') are the most abundant and widespread species of primate, characterized by bipedalism and exceptional cognitive skills due to a large and complex brain. This has enabled the development of advanced tools, culture, ...
s.
Also called mias by the local population, the Bornean orangutan is a
critically endangered species, with
deforestation
Deforestation or forest clearance is the removal of a forest or stand of trees from land that is then converted to non-forest use. Deforestation can involve conversion of forest land to farms, ranches, or urban use. The most concentrated d ...
,
palm oil
Palm oil is an edible vegetable oil derived from the mesocarp (reddish pulp) of the fruit of the oil palms. The oil is used in food manufacturing, in beauty products, and as biofuel. Palm oil accounted for about 33% of global oils produced from ...
plantations, and
hunting
Hunting is the human activity, human practice of seeking, pursuing, capturing, or killing wildlife or feral animals. The most common reasons for humans to hunt are to harvest food (i.e. meat) and useful animal products (fur/hide (skin), hide, ...
posing a serious threat to its continued existence.
Taxonomy
![Orangutan Kalimantan](https://upload.wikimedia.org/wikipedia/commons/a/ad/Orangutan_Kalimantan.jpg)
The Bornean orangutan and the
Sumatran orangutan
The Sumatran orangutan (''Pongo abelii'') is one of the three species of orangutans. Critically Endangered, and found only in the north of the Indonesian island of Sumatra, it is rarer than the Bornean orangutan but more common than the recent ...
diverged about 400,000 years ago,
with a continued low level of gene flow between them since then.
The two orangutan species were considered merely
subspecies
In biological classification, subspecies is a rank below species, used for populations that live in different areas and vary in size, shape, or other physical characteristics (morphology), but that can successfully interbreed. Not all species ...
until 1996; they were elevated to species following sequencing of their
mitochondrial DNA
Mitochondrial DNA (mtDNA or mDNA) is the DNA located in mitochondria, cellular organelles within eukaryotic cells that convert chemical energy from food into a form that cells can use, such as adenosine triphosphate (ATP). Mitochondrial D ...
.
The Bornean orangutan has three subspecies:
*Northwest Bornean orangutan ''Pongo pygmaeus pygmaeus'' –
Sarawak
Sarawak (; ) is a States and federal territories of Malaysia, state of Malaysia. The largest among the 13 states, with an area almost equal to that of Peninsular Malaysia, Sarawak is located in northwest Borneo Island, and is bordered by the M ...
(
Malaysia
Malaysia ( ; ) is a country in Southeast Asia. The federation, federal constitutional monarchy consists of States and federal territories of Malaysia, thirteen states and three federal territories, separated by the South China Sea into two r ...
) and northern
West Kalimantan
West Kalimantan ( id, Kalimantan Barat) is a province of Indonesia. It is one of five Indonesian provinces comprising Kalimantan, the Indonesian part of the island of Borneo. Its capital city is Pontianak, Indonesia, Pontianak. The province has ...
(
Indonesia
Indonesia, officially the Republic of Indonesia, is a country in Southeast Asia and Oceania between the Indian and Pacific oceans. It consists of over 17,000 islands, including Sumatra, Java, Sulawesi, and parts of Borneo and New Guine ...
).
*Central Bornean orangutan ''P. p. wurmbii'' – Southern West Kalimantan and
Central Kalimantan
Central Kalimantan ( id, Kalimantan Tengah) is a province of Indonesia. It is one of five provinces in Kalimantan, the Indonesian part of Borneo. Its provincial capital is Palangka Raya and in 2010 its population was over 2.2 million, while the 2 ...
(Indonesia).
*Northeast Bornean orangutan ''P. p. morio'' –
East Kalimantan
East Kalimantan (Indonesian: ) is a province of Indonesia. Its territory comprises the eastern portion of Borneo. It had a population of about 3.03 million at the 2010 census (within the current boundary), 3.42 million at the 2015 census, and 3. ...
(Indonesia) and
Sabah
Sabah () is a States and federal territories of Malaysia, state of Malaysia located in northern Borneo, in the region of East Malaysia. Sabah borders the Malaysian state of Sarawak to the southwest and the North Kalimantan province of Indone ...
(Malaysia).
There is some uncertainty about this, however. The population currently listed as ''P. p. wurmbii'' may be closer to the Sumatran orangutan (''P. abelii'') than to the Bornean orangutan. If this is confirmed, ''P. abelii'' would be a subspecies of ''P. wurmbii'' (Tiedeman, 1808).
In addition, the
type locality of ''P. pygmaeus'' has not been established beyond doubt; it may be from the population currently listed as ''P. wurmbii'' (in which case ''P. wurmbii'' would be a
junior synonym
The Botanical and Zoological Codes of nomenclature treat the concept of synonymy differently.
* In botanical nomenclature, a synonym is a scientific name that applies to a taxon that (now) goes by a different scientific name. For example, Linna ...
of ''P. pygmaeus'', while one of the names currently considered a junior synonym of ''P. pygmaeus'' would take precedence for the
taxon
In biology, a taxon (back-formation from ''taxonomy''; plural taxa) is a group of one or more populations of an organism or organisms seen by taxonomists to form a unit. Although neither is required, a taxon is usually known by a particular nam ...
in Sarawak and northern West Kalimantan).
Bradon-Jones ''et al.'' considered ''P. morio'' to be a synonym of ''P. pygmaeus'', and the population found in East Kalimantan and Sabah to be a potentially unnamed separate taxon.
In early October 2014, researchers from domestic and foreign countries found about 50 orangutans in several groups in
South Kalimantan
South Kalimantan ( id, Kalimantan Selatan) is a Provinces of Indonesia, province of Indonesia. It is the smallest province in Kalimantan, the Indonesian territory of Borneo. The provincial capital was Banjarmasin until 15 February 2022 when it wa ...
Province, although previously there is no record that the province has orangutans.
As a member of the family
Hominidae
The Hominidae (), whose members are known as the great apes or hominids (), are a taxonomic family of primates that includes eight extant species in four genera: '' Pongo'' (the Bornean, Sumatran and Tapanuli orangutan); ''Gorilla'' (the ea ...
, Bornean orangutans are one of the closest extant relatives to ''Homo sapiens''.
This species was originally discovered by native Malaysians. There are several mentions of orangutans in Malaysian folklore. However, this species was originally named and described by the notable zoologist Carl Linnaeus in 1799. Its original name was ''Simia satyrus'', meaning "satyr monkey", but was changed when scientists discovered that not all orangutans are one species. The
holotype
A holotype is a single physical example (or illustration) of an organism, known to have been used when the species (or lower-ranked taxon) was formally described. It is either the single such physical example (or illustration) or one of several ...
of this organism is located in the British Museum in London.
The current species name ''P. pygmaeus'' is not Latin unlike most other Linnean classifications. The genus name ''Pongo'' is derived from the Bantu word ' used to indicate a large primate. It was originally used to describe
chimpanzee
The chimpanzee (''Pan troglodytes''), also known as simply the chimp, is a species of great ape native to the forest and savannah of tropical Africa. It has four confirmed subspecies and a fifth proposed subspecies. When its close relative th ...
s in Western African dialects. The species name ''pygmaeus'' is derived from the Greek word "pygmy" meaning dwarf.
Physical description
![Orang-Utan Tournai](https://upload.wikimedia.org/wikipedia/commons/5/5a/Orang-Utan_Tournai.jpg)
The Bornean orangutan is the third-largest
ape
Apes (collectively Hominoidea ) are a clade of Old World simians native to sub-Saharan Africa and Southeast Asia (though they were more widespread in Africa, most of Asia, and as well as Europe in prehistory), which together with its siste ...
after the
western gorilla
The western gorilla (''Gorilla gorilla'') is a great ape found in Africa, one of two species of the hominid genus ''Gorilla''. Large and robust with males weighing around , the hair is significantly lighter in color than the eastern gorilla, ''G ...
, and the largest truly
arboreal
Arboreal locomotion is the Animal locomotion, locomotion of animals in trees. In habitats in which trees are present, animals have evolved to move in them. Some animals may scale trees only occasionally, but others are exclusively arboreal. Th ...
(or tree-dwelling) extant ape. Body weights broadly overlap with the considerably taller ''Homo sapiens'', but the latter is considerably more variable in size.
[Novak, R. M. 1999. ''Walker's Mammals of the World.'' 6th edition. Johns Hopkins University Press, Baltimore. ] By comparison, the Sumatran orangutan is similar in size but, on average, is marginally lighter in weight. A survey of wild orangutans found that males weigh on average , ranging from , and long; females average , ranging from , and long.
While in captivity, orangutans can grow considerably overweight, up to more than . The heaviest known male orangutan in captivity was an obese male named "Andy", who weighed in 1959 when he was 13 years old.
The Bornean orangutan has a distinctive body shape with very long arms that may reach up to 1.5 metres in length. It has grey skin, a coarse, shaggy, reddish coat and
prehensile
Prehensility is the quality of an appendage or organ (anatomy), organ that has Adaptation (biology), adapted for grasping or holding. The word is derived from the Latin term ''prehendere'', meaning "to grasp". The ability to grasp is likely der ...
, grasping hands and feet.
Its coat does not cover its face unlike most mammals, although Bornean orangutans do have some hair on their faces including a beard and mustache. It also has large, fatty cheek pads known as flanges as well as a pendulous throat sac.
![Orangutan (bornean) 02](https://upload.wikimedia.org/wikipedia/commons/a/af/Orangutan_%28bornean%29_02.JPG)
Bornean orangutans are highly sexually dimorphic and have several features that differ between males and females. Males have much larger cheek pads, or flanges, that are composed of muscle and large amounts of fat. In females, the flanges are mostly composed of muscle. Males have relatively larger canines and premolars. Males have a more pronounced beard and mustache. The throat sac in males is also considerably larger. There are two body types for sexually mature males: smaller or larger. Larger males are more dominant but smaller males still breed successfully. There is little sexual dimorphism at birth.
Habitat and distribution
The Bornean orangutan lives in
tropical and subtropical moist broadleaf forest
Tropical and subtropical moist broadleaf forests (TSMF), also known as tropical moist forest, is a subtropical and tropical forest habitat type defined by the World Wide Fund for Nature.
Description
TSMF is generally found in large, discont ...
in the Bornean lowlands, as well as mountainous areas up to above sea level.
This species lives throughout the canopy of
primary
Primary or primaries may refer to:
Arts, entertainment, and media Music Groups and labels
* Primary (band), from Australia
* Primary (musician), hip hop musician and record producer from South Korea
* Primary Music, Israeli record label
Works
* ...
and
secondary
Secondary may refer to: Science and nature
* Secondary emission, of particles
** Secondary electrons, electrons generated as ionization products
* The secondary winding, or the electrical or electronic circuit connected to the secondary winding i ...
forest, and moves large distances to find trees bearing fruit.
It is found in the two Malaysian states of
Sabah
Sabah () is a States and federal territories of Malaysia, state of Malaysia located in northern Borneo, in the region of East Malaysia. Sabah borders the Malaysian state of Sarawak to the southwest and the North Kalimantan province of Indone ...
and
Sarawak
Sarawak (; ) is a States and federal territories of Malaysia, state of Malaysia. The largest among the 13 states, with an area almost equal to that of Peninsular Malaysia, Sarawak is located in northwest Borneo Island, and is bordered by the M ...
, and four of the five Indonesian Provinces of
Kalimantan
Kalimantan () is the Indonesian portion of the island of Borneo. It constitutes 73% of the island's area. The non-Indonesian parts of Borneo are Brunei and East Malaysia. In Indonesia, "Kalimantan" refers to the whole island of Borneo.
In 2019, ...
.
Due to habitat destruction, the species distribution is now highly patchy throughout the island, the species has become rare in the southeast of the island, as well as in the forest between the
Rajang River
The Rajang River ( ms, Batang Rajang) is a river in Sarawak, northwest Borneo, Malaysia. The river originates in the Iran Mountains, flows through Kapit, and then towards the South China Sea. At approximately , the river is the seventh-longest i ...
in central Sarawak and the Padas River in western Sabah. Its presence in
Brunei
Brunei ( , ), formally Brunei Darussalam ( ms, Negara Brunei Darussalam, Jawi alphabet, Jawi: , ), is a country located on the north coast of the island of Borneo in Southeast Asia. Apart from its South China Sea coast, it is completely sur ...
is uncertain and unconfirmed.
The first complete orangutan skeleton that was discovered was in the
Hoa Binh province in Vietnam and thought to be from the late
Pleistocene
The Pleistocene ( , often referred to as the ''Ice age'') is the geological Epoch (geology), epoch that lasted from about 2,580,000 to 11,700 years ago, spanning the Earth's most recent period of repeated glaciations. Before a change was fina ...
epoch. It differed from modern orangutans only in that its body was proportionately smaller compared to its head. This fossil and others confirm that orangutans once inhabited continental Southeast Asia even though currently, Bornean orangutans are only found in Malaysia and Indonesia.
Behavior and ecology
![Bornean Orangutan in nest](https://upload.wikimedia.org/wikipedia/commons/4/48/Bornean_Orangutan_in_nest.jpg)
In history, orangutans ranged throughout Southeast Asia and into southern China, as well as on the island of Java and in southern Sumatra. They primarily inhabit peat swamp forest, tropical heath forest, and mixed dipterocarp forest.
Bornean orangutan are more solitary than their Sumatran relatives. Two or three orangutans with overlapping territories may interact, but only for short periods of time.
Although orangutans are not territorial, adult males will display threatening behaviors upon meeting other males, and only socialize with females to mate.
Males are considered the most solitary of the orangutans. The Bornean orangutan has a lifespan of 35–45 years in the wild;
in
captivity
Captivity, or being held captive, is a state wherein humans or other animals are confined to a particular space and prevented from leaving or moving freely. An example in humans is imprisonment. Prisoners of war are usually held in captivity by a ...
it can live to be about 60.
Despite being
arboreal
Arboreal locomotion is the Animal locomotion, locomotion of animals in trees. In habitats in which trees are present, animals have evolved to move in them. Some animals may scale trees only occasionally, but others are exclusively arboreal. Th ...
, the Bornean orangutan travels on the ground more than its Sumatran counterpart. This may be in part because no large terrestrial predators could threaten an orangutan in Borneo. In Sumatra, orangutans must face predation by the fierce
Sumatran tiger
The Sumatran tiger is a population of ''Panthera tigris sondaica'' on the Indonesian island of Sumatra. It is the only surviving tiger population in the Sunda Islands, where the Bali and Javan tigers are extinct.
Sequences from complete mitochon ...
.
The Bornean orangutan exhibits
nest-building behavior. Nests are built for use at night or during the day. Young orangutans learn by observing their mother's nest-building behaviour. This skill is practiced by juvenile orangutans. Nests may be elaborate and involve a foundation and mattress made by intertwining leaves and branches and adding broken leafy branches. Additional features such as shade, waterproof roof, "pillow", and "blanket", all of which are made from branches, twigs and leaves, may also be added.
Nest-building in primates is considered as an example of
tool use
Tool use by animals is a phenomenon in which an animal uses any kind of tool in order to achieve a goal such as acquiring food and water, grooming, defence, communication, recreation or construction. Originally thought to be a skill possessed ...
and not
animal architecture
Structures built by animals, often called animal architecture, abound in nature. Examples of animal structures include termite mounds, wasp and beehives, burrow complexes of rodents, beaver dams, elaborate nests of birds, and webs of spiders.
...
.
Diet
The Bornean orangutan diet is composed of over 400 types of food, including wild
fig
The fig is the edible fruit of ''Ficus carica'', a species of small tree in the flowering plant family Moraceae. Native to the Mediterranean and western Asia, it has been cultivated since ancient times and is now widely grown throughout the world ...
s,
durian
The durian (, ) is the edible fruit of several tree species belonging to the genus ''Durio''. There are 30 recognised ''Durio'' species, at least nine of which produce edible fruit. ''Durio zibethinus'', native to Borneo and Sumatra, is the onl ...
s (''
Durio zibethinus
''Durio zibethinus'' is the most common tree species in the genus ''Durio'' that are known as durian and have edible fruit also known as durian.
As with most other durian species, the edible flesh emits a distinctive odour that is strong and pen ...
'' and ''
D. graveolens''),
leaves
A leaf (plural, : leaves) is any of the principal appendages of a vascular plant plant stem, stem, usually borne laterally aboveground and specialized for photosynthesis. Leaves are collectively called foliage, as in "autumn foliage", wh ...
,
seed
A seed is an embryonic plant enclosed in a protective outer covering, along with a food reserve. The formation of the seed is a part of the process of reproduction in seed plants, the spermatophytes, including the gymnosperm and angiospe ...
s,
bird egg
Bird eggs are laid by the females and range in quantity from one (as in condors) to up to seventeen (the grey partridge). Clutch size may vary latitudinally within a species. Some birds lay eggs even when the eggs have not been fertilized; it is ...
s, flowers,
sap
Sap is a fluid transported in xylem cells (vessel elements or tracheids) or phloem sieve tube elements of a plant. These cells transport water and nutrients throughout the plant.
Sap is distinct from latex, resin, or cell sap; it is a separa ...
,
vine
A vine (Latin ''vīnea'' "grapevine", "vineyard", from ''vīnum'' "wine") is any plant with a growth habit of trailing or scandent (that is, climbing) stems, lianas or runners. The word ''vine'' can also refer to such stems or runners themselv ...
s,
honey
Honey is a sweet and viscous substance made by several bees, the best-known of which are honey bees. Honey is made and stored to nourish bee colonies. Bees produce honey by gathering and then refining the sugary secretions of plants (primar ...
,
fungi
A fungus ( : fungi or funguses) is any member of the group of eukaryotic organisms that includes microorganisms such as yeasts and molds, as well as the more familiar mushrooms. These organisms are classified as a kingdom, separately from ...
,
spider web
A spider web, spiderweb, spider's web, or cobweb (from the archaic word '' coppe'', meaning "spider") is a structure created by a spider out of proteinaceous spider silk extruded from its spinnerets, generally meant to catch its prey.
Spid ...
s,
insects, and, to a lesser extent than the Sumatran orangutan,
bark.
They have also been known to consume the inner shoots of plants and vines.
They will also occasionally eat nutrient rich
soil
Soil, also commonly referred to as earth or dirt, is a mixture of organic matter, minerals, gases, liquids, and organisms that together support life. Some scientific definitions distinguish ''dirt'' from ''soil'' by restricting the former te ...
.
They get the necessary quantities of water from both fruit and from tree holes.
![How to peel a banana with your foot (26443349170)](https://upload.wikimedia.org/wikipedia/commons/a/ad/How_to_peel_a_banana_with_your_foot_%2826443349170%29.jpg)
Bornean orangutans have been sighted
using spears to attempt (unsuccessfully) to catch fish. The species has been observed using tools such as leaves to wipe off faeces, a pad of leaves for holding spiny durian fruit, a leafy branch for a bee swatter, a bunch of leafy branches held together as an "umbrella" while traveling in the rain, a single stick as backscratcher, and a branch or tree trunk as a missile. In some regions, orangutans occasionally eat soil to get minerals that may neutralize the toxins and acids they consume in their primarily vegetarian diets.
On rare occasions, orangutans will prey upon other, smaller primates, such as
slow loris
Slow lorises are a group of several species of nocturnal strepsirrhine primates that make up the genus ''Nycticebus''. Found in Southeast Asia and bordering areas, they range from Bangladesh and Northeast India in the west to the Sulu Archipe ...
es.
Reproduction
![Orang Utan (Pongo pygmaeus) female with baby (8066259067)](https://upload.wikimedia.org/wikipedia/commons/0/0a/Orang_Utan_%28Pongo_pygmaeus%29_female_with_baby_%288066259067%29.jpg)
Males and females generally come together only to mate. Subadult males (unflanged) will try to mate with any female and will be successful around half the time.
Dominant flanged males will call and advertise their position to receptive females, who prefer mating with flanged males.
Adult males will often target females with weaned infants as mating partners because the female is likely to be fertile.
Females reach sexual maturity and experience their first ovulatory cycle between about six and 11 years of age, although females with more body fat may experience this at an earlier age.
The estrous cycle lasts between 22 and 30 days and menopause has been reported in captive orangutans at about age 48.
Females tend to give birth at about 14–15 years of age. Newborn orangutans nurse every three to four hours, and begin to take soft food from their mothers' lips by four months. During the first year of its life, the young clings to its mother's abdomen by entwining its fingers in and gripping her hair. Offspring are
weaned
Weaning is the process of gradually introducing an infant human or another mammal to what will be its adult diet while withdrawing the supply of its mother's milk.
The process takes place only in mammals, as only mammals produce milk. The infan ...
at about four years, but this could be much longer, and soon after they start their adolescent stage of exploring, but always within sight of their mother.
During this period, they will also actively seek other young orangutans to play with and travel with. On average, juveniles do not become completely independent until they are about seven years of age. The birth rate for orangutans has been decreasing largely due to a lack of sufficient nutrients as a result of habitat loss.
A 2011 study on female orangutans in free-ranging rehabilitation programs found that individuals that were supplemented with food resources had shorter interbirth intervals, as well as a reduced age, at first birth.
Conservation status
The Bornean orangutan is more common than the Sumatran, with about 104,700 individuals in the wild, whereas just under 14,000 Sumatran orangutans are left in the wild.
Orangutans are becoming increasingly endangered due to habitat destruction and the
bushmeat
Bushmeat is meat from wildlife species that are hunted for human consumption, most often referring to the meat of game in Africa. Bushmeat represents
a primary source of animal protein and a cash-earning commodity for inhabitants of humid tropi ...
trade, and young orangutans are captured to be sold as pets, usually entailing the killing of their mothers.
The Bornean orangutan is
critically endangered according to the
IUCN Red List
The International Union for Conservation of Nature (IUCN) Red List of Threatened Species, also known as the IUCN Red List or Red Data Book, founded in 1964, is the world's most comprehensive inventory of the global conservation status of biol ...
of
mammal
Mammals () are a group of vertebrate animals constituting the class Mammalia (), characterized by the presence of mammary glands which in females produce milk for feeding (nursing) their young, a neocortex (a region of the brain), fur or ...
s, and is listed on Appendix I of
CITES
CITES (shorter name for the Convention on International Trade in Endangered Species of Wild Fauna and Flora, also known as the Washington Convention) is a multilateral treaty to protect endangered plants and animals from the threats of interna ...
. The total number of Bornean orangutans is estimated to be less than 14% of what it was in the recent past (from around 10,000 years ago until the middle of the 20th century), and this sharp decline has occurred mostly over the past few decades due to human activities and development.
Species distribution is now highly patchy throughout Borneo; it is apparently absent or uncommon in the southeast of the island, as well as in the forest between the
Rajang River
The Rajang River ( ms, Batang Rajang) is a river in Sarawak, northwest Borneo, Malaysia. The river originates in the Iran Mountains, flows through Kapit, and then towards the South China Sea. At approximately , the river is the seventh-longest i ...
in central
Sarawak
Sarawak (; ) is a States and federal territories of Malaysia, state of Malaysia. The largest among the 13 states, with an area almost equal to that of Peninsular Malaysia, Sarawak is located in northwest Borneo Island, and is bordered by the M ...
and the Padas River in western
Sabah
Sabah () is a States and federal territories of Malaysia, state of Malaysia located in northern Borneo, in the region of East Malaysia. Sabah borders the Malaysian state of Sarawak to the southwest and the North Kalimantan province of Indone ...
(including the Sultanate of
Brunei
Brunei ( , ), formally Brunei Darussalam ( ms, Negara Brunei Darussalam, Jawi alphabet, Jawi: , ), is a country located on the north coast of the island of Borneo in Southeast Asia. Apart from its South China Sea coast, it is completely sur ...
).
A population of around 6,900 is found in
Sabangau National Park
Sabangau National Park (sometimes spelled Sebangau) is a national park in Central Kalimantan, a province of Indonesia in Kalimantan, the Indonesian part of the island of Borneo established in 2004. Between 1980 and 1995 the site was a massive ...
, but this environment is at risk.
This view is also supported by the
United Nations Environment Programme
The United Nations Environment Programme (UNEP) is responsible for coordinating responses to environmental issues within the United Nations system. It was established by Maurice Strong, its first director, after the United Nations Conference on th ...
, which stated in its 2007 report that, due to
illegal logging
Illegal logging is the harvest, transportation, purchase or sale of timber in violation of laws. The harvesting procedure itself may be illegal, including using corrupt means to gain access to forests; extraction without permission, or from a pro ...
,
fire
Fire is the rapid oxidation of a material (the fuel) in the exothermic chemical process of combustion, releasing heat, light, and various reaction Product (chemistry), products.
At a certain point in the combustion reaction, called the ignition ...
and the extensive development of
palm oil
Palm oil is an edible vegetable oil derived from the mesocarp (reddish pulp) of the fruit of the oil palms. The oil is used in food manufacturing, in beauty products, and as biofuel. Palm oil accounted for about 33% of global oils produced from ...
plantations, orangutans are critically endangered, and if the current trend continues, they will become extinct.
When forest is burned down to clear room for palm oil plantations, not only does the Bornean orangutan suffer from habitat loss, but several individuals have been burned and killed in fires. Palm oil accounts for over one tenth of Indonesia's export earnings. It is in high demand because it is used in several packaged foods, deodorants, shampoos, soaps, candies, and baked goods.
Climate change is another threat to Bornean orangutan conservation. The effects that human activity have had on Indonesian rainfall have made food less abundant and so Bornean orangutans are less likely to receive full nutrients so that they can be sufficiently healthy to breed.
A November 2011 survey, based on interviews with 6,983 respondents in 687 villages across Kalimantan in 2008 to 2009, gave estimated orangutan killing rates of between 750 and 1800 in the year leading up to April 2008.
These killing rates were higher than previously thought and confirm that the continued existence of the orangutan in Kalimantan is under serious threat. The survey did not quantify the additional threat to the species due to habitat loss from deforestation and expanding palm-oil plantations. The survey found that 73% of respondents knew orangutans were protected by Indonesian law.
[
]
However, the Indonesian government rarely prosecutes or punishes perpetrators. In a rare prosecution in November 2011, two men were arrested for killing at least 20 orangutans and a number of long-nosed proboscis monkey
The proboscis monkey (''Nasalis larvatus'') or long-nosed monkey is an arboreal Old World monkey with an unusually large nose, a reddish-brown skin color and a long tail. It is endemic to the southeast Asian island of Borneo and is found mostly ...
s. They were ordered to conduct the killings by the supervisor of a palm oil plantation, to protect the crop, with a payment of $100 for a dead orangutan and $22 for a monkey.
Rescue and rehabilitation centers
A number of orangutan rescue and rehabilitation projects operate in Borneo.
The Borneo Orangutan Survival Foundation (BOS) founded by Dr Willie Smits
Willie Smits (born February 22, 1957, in Weurt, Gelderland, the Netherlands) is a trained forester, a microbiologist, conservationist, animal rights activist, wilderness engineer and social entrepreneur. He has lived in Indonesia since 1985 an ...
has rescue and rehabilitation centres at Wanariset and Samboja Lestari
Samboja Lestari is a Bornean orangutan (''Pongo pygmaeus'') rescue and rehabilitation centre, tropical rainforest restoration project, sun bear sanctuary, and eco-lodge located in the town of Samboja in East Kalimantan, Indonesia, owned and operat ...
in East Kalimantan
East Kalimantan (Indonesian: ) is a province of Indonesia. Its territory comprises the eastern portion of Borneo. It had a population of about 3.03 million at the 2010 census (within the current boundary), 3.42 million at the 2015 census, and 3. ...
and Nyaru Menteng, in Central Kalimantan
Central Kalimantan ( id, Kalimantan Tengah) is a province of Indonesia. It is one of five provinces in Kalimantan, the Indonesian part of Borneo. Its provincial capital is Palangka Raya and in 2010 its population was over 2.2 million, while the 2 ...
founded and managed by Lone Drøscher Nielsen
Lone Drøscher Nielsen (born 1964) is a Danish wildlife conservationist who established the Nyaru Menteng Orangutan Reintroduction Project in Kalimantan, Borneo, Indonesia in 1998.
Early life and work
She was born and grew up in Aabybro, Denmark. ...
. BOS also works to conserve and recreate the fast-disappearing rainforest habitat of the orangutan, at Samboja Lestari and Mawas.
Orangutan Foundation International Orangutan Foundation International (OFI) has its headquarters in Los Angeles, California. Founded by Dr. Birutė Galdikas, one of three anthropologists (The Trimates) to study great apes under the guidance of Dr. Louis Leakey, OFI continues to res ...
, founded by Dr Birutė Galdikas
Birutė Marija Filomena Galdikas or Birutė Mary Galdikas, OC (born 10 May 1946), is a Lithuanian-Canadian anthropologist, primatologist, conservationist, ethologist, and author. She is a professor at Simon Fraser University. In the field of ...
, rescues and rehabilitates orangutans, preparing them for release back into protected areas of the Indonesian rain forest. In addition, it promotes the preservation of the rain forest for them.
The Sepilok Orangutan Rehabilitation Centre
Sepilok Orangutan Rehabilitation Centre is located about 25 kilometres west of Sandakan in the state of Sabah, Malaysia.
The centre opened in 1964 as the first official orangutan rehabilitation project for rescued orphaned baby orangutans from ...
near Sandakan
Sandakan (, Jawi: , ) formerly known at various times as Elopura, is the capital of the Sandakan District in Sabah, Malaysia. It is the second largest city in Sabah after Kota Kinabalu. It is located on the Sandakan Peninsula and east coast of ...
in the state of Sabah
Sabah () is a States and federal territories of Malaysia, state of Malaysia located in northern Borneo, in the region of East Malaysia. Sabah borders the Malaysian state of Sarawak to the southwest and the North Kalimantan province of Indone ...
in Malaysia
Malaysia ( ; ) is a country in Southeast Asia. The federation, federal constitutional monarchy consists of States and federal territories of Malaysia, thirteen states and three federal territories, separated by the South China Sea into two r ...
n Borneo
Borneo (; id, Kalimantan) is the third-largest island in the world and the largest in Asia. At the geographic centre of Maritime Southeast Asia, in relation to major Indonesian islands, it is located north of Java, west of Sulawesi, and eas ...
opened in 1964 as the first official orangutan rehabilitation project.
Orangutan Foundation
Orangutans are great apes native to the rainforests of Indonesia and Malaysia. They are now found only in parts of Borneo and Sumatra, but during the Pleistocene they ranged throughout Southeast Asia and South China. Classified in the genus ' ...
, founded by Ashley Leiman, operates programmes in Central Kalimantan
Central Kalimantan ( id, Kalimantan Tengah) is a province of Indonesia. It is one of five provinces in Kalimantan, the Indonesian part of Borneo. Its provincial capital is Palangka Raya and in 2010 its population was over 2.2 million, while the 2 ...
, Indonesian Borneo. The Foundation rescues orphaned orangutans and enters them into their soft-release programme, allowing them to develop the skills necessary to survive in the wild. When old enough, orangutans are released into the protected Lamandau Wildlife Reserve. Orangutan Foundation works to protect orangutans by focusing on habitat protection and capacity building, especially in local communities.
A seven-year longitudinal study published in 2011 looked at whether the lifespan of zoo-housed orangutans was related to a subjective assessment of well-being, with the intent of applying such measures to assess the welfare of orangutans in captivity. Of the subjects, 100 were Sumatran (''Pongo abelii''), 54 Bornean (''Pongo pygmaeus'') and 30 were hybrid orangutan
A hybrid orangutan or cocktail orangutan is usually an orangutan derived from interbreeding between any of the three Orangutan species: Bornean (''Pongo pygmaeus''), Sumatran (''Pongo abelii'') and Tapanuli (''Pongo tapanuliensis''), but the te ...
s. 113 zoo employees, who were highly familiar with the typical behavior of the orangutans, used a four-item questionnaire to assess their subjective well-being. The results indicated that orangutans in higher subjective well-being were less likely to die during the follow-up period. The study concluded that happiness was related to longer life in orangutans.
In late 2014, Nyaru Menteng veterinarians failed to rescue the life of a female orangutan. An operation was performed in which 40 air-rifle pellets were removed from her body. The orangutan was found at a palm oil plantation in Indonesian Borneo.
Genome and Demographic History
Orangutans and humans diverged lineages approximately 14-18 million years ago. About 17,000 years ago, there was a migration of the Bornean orangutans as they eventually went to Sumatra
Sumatra is one of the Sunda Islands of western Indonesia. It is the largest island that is fully within Indonesian territory, as well as the sixth-largest island in the world at 473,481 km2 (182,812 mi.2), not including adjacent i ...
, effectively trading places with the Sumatra orangutans that were there at the time. These two species of orangutans have been closely related throughout their evolutionary history due to the fact that they were so close in physical proximity. Therefore, their genomes and demographic history are similar. The two species themselves are estimated to have split about 3.5 million years ago. Although these two species have officially diverged, it is speculated that the reason as to why they are genetically similar is because the males of each respective species tend to migrate between the two islands and breed with the females from their sister species. As a result, both the Bornean orangutans and the Sumatran orangutan
The Sumatran orangutan (''Pongo abelii'') is one of the three species of orangutans. Critically Endangered, and found only in the north of the Indonesian island of Sumatra, it is rarer than the Bornean orangutan but more common than the recent ...
s have been studied closely as a pair, and thus much genome findings attribute evolutionary changes to this relationship. In addition, the Bornean orangutans, as compared to the Sumatran orangutan
The Sumatran orangutan (''Pongo abelii'') is one of the three species of orangutans. Critically Endangered, and found only in the north of the Indonesian island of Sumatra, it is rarer than the Bornean orangutan but more common than the recent ...
s, have lower autosomal gene diversity
Genetic diversity is the total number of genetic characteristics in the genetic makeup of a species, it ranges widely from the number of species to differences within species and can be attributed to the span of survival for a species. It is dis ...
. This is attributed to the fact that they have a much smaller population size. Also, the Bornean orangutans have lower nucleotide diversity Nucleotide diversity is a concept in molecular genetics which is used to measure the degree of polymorphism within a population.
One commonly used measure of nucleotide diversity was first introduced by Nei and Li in 1979. This measure is defin ...
.
As the Bornean orangutans and Sumatra orangutans both exist within the same species, they exhibit similar cultural behaviors that have been found to exist amongst most orangutan populations. The fact that orangutans tend to showcase similar cultural traditions is due to the fact that they typically live in similar environments and are adept at learning from one another from their early stages of life.
The Bornean orangutan has been linked to the fact that it has gone through a deep divergence in relation to its relatives and ancestors. During the Middle Pleistocene
The Chibanian, widely known by its previous designation of Middle Pleistocene, is an age in the international geologic timescale or a stage in chronostratigraphy, being a division of the Pleistocene Epoch within the ongoing Quaternary Period. The ...
, there were low levels of gene flow, which was determined through the analysis of Y-chromosomal data. One reason as to why this may have occurred is because of the Sunda shelf
Geologically, the Sunda Shelf is a south-eastern extension of the continental shelf of Mainland Southeast Asia. Major landmasses on the shelf include the Bali, Borneo, Java, Madura, and Sumatra, as well as their surrounding smaller islands. ...
, which is where the island of Borneo
Borneo (; id, Kalimantan) is the third-largest island in the world and the largest in Asia. At the geographic centre of Maritime Southeast Asia, in relation to major Indonesian islands, it is located north of Java, west of Sulawesi, and eas ...
is located. During this time, this event's dry climate during the Late Pleistocene
The Late Pleistocene is an unofficial Age (geology), age in the international geologic timescale in chronostratigraphy, also known as Upper Pleistocene from a Stratigraphy, stratigraphic perspective. It is intended to be the fourth division of ...
attributed to a more abundant genetic exchange. As a result, there were many early divergences of gene pools between the Bornean orangutans, as well as the Sumatran orangutan
The Sumatran orangutan (''Pongo abelii'') is one of the three species of orangutans. Critically Endangered, and found only in the north of the Indonesian island of Sumatra, it is rarer than the Bornean orangutan but more common than the recent ...
s. Relating back to the Middle Pleistocene
The Chibanian, widely known by its previous designation of Middle Pleistocene, is an age in the international geologic timescale or a stage in chronostratigraphy, being a division of the Pleistocene Epoch within the ongoing Quaternary Period. The ...
, the Bornean orangutan lineage went through a dramatic population decline. This is likely attributed to the fact that they had been isolated from their ancestral populations. Therefore, natural geographic barriers are attributed to be the reason as to why the Bornean orangutans were eventually isolated and ended up colonizing other regions. In addition, this geographic isolation also indicates that the Bornean orangutans did not undergo a severe genetic bottleneck
A population bottleneck or genetic bottleneck is a sharp reduction in the size of a population due to environmental events such as famines, earthquakes, floods, fires, disease, and droughts; or human activities such as specicide, widespread violen ...
. With the Borneo orangutan, selection was found to have been found through physiological adaptations – most of which has to do with being able to adapt to the ever-changing climate on the Borneo island.
See also
* Deforestation in Borneo
Deforestation in Borneo has taken place on an industrial scale since the 1960s. Borneo, the third largest island in the world, divided between Indonesia, Malaysia and Brunei, was once covered by dense tropical and subtropical rainforests.
In th ...
* Social and environmental impact of palm oil
Palm oil, produced from the oil palm, is a basic source of income for many farmers in South East Asia, Central and West Africa, and Central America. It is locally used as cooking oil, exported for use in much commercial food and personal care produ ...
References
Further reading
External links
*
The Borneo Orangutan Survival Foundation (BOS)
World Wildlife Fund: Orangutans
Orangutan Foundation International
Sepilok Orang Utan Sanctuary
{{Taxonbar, from=Q599672
Bornean orangutan
The Bornean orangutan (''Pongo pygmaeus'') is a species of orangutan endemic to the island of Borneo. Together with the Sumatran orangutan (''Pongo abelii'') and Tapanuli orangutan (''Pongo tapanuliensis''), it belongs to the only genus of great ...
Endemic fauna of Borneo
Mammals of Borneo
Mammals of Malaysia
East Kalimantan
Sabah
Sarawak
Bornean orangutan
The Bornean orangutan (''Pongo pygmaeus'') is a species of orangutan endemic to the island of Borneo. Together with the Sumatran orangutan (''Pongo abelii'') and Tapanuli orangutan (''Pongo tapanuliensis''), it belongs to the only genus of great ...
Bornean orangutan
The Bornean orangutan (''Pongo pygmaeus'') is a species of orangutan endemic to the island of Borneo. Together with the Sumatran orangutan (''Pongo abelii'') and Tapanuli orangutan (''Pongo tapanuliensis''), it belongs to the only genus of great ...
Critically endangered fauna of Asia
Species endangered by oil palm plantations