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 ea ...

is the third largest island in the world. In prehistoric times it was connected to the Asian mainland due to geological and climate changes. During the recent

ice age An ice age is a long period of reduction in the temperature of Earth's surface and atmosphere, resulting in the presence or expansion of continental and polar ice sheets and alpine glaciers. Earth's climate alternates between ice ages and gre ...

s of the

Pleistocene The Pleistocene ( , often referred to as the ''Ice age'') is the geological 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 finally confirmed in ...

and the

Holocene The Holocene ( ) is the current geological epoch. It began approximately 11,650 cal years Before Present (), after the Last Glacial Period, which concluded with the Holocene glacial retreat. The Holocene and the preceding Pleistocene togeth ...

separation from the mainland caused extinctions and speciation of fauna on the island. The high complexity of the Bornean

tropical rain forest Tropical rainforests are rainforests that occur in areas of tropical rainforest climate in which there is no dry season – all months have an average precipitation of at least 60 mm – and may also be referred to as ''lowland equatori ...

has created many niches that accommodate a rich diversity of fauna. Some fauna are specialised and some coexisted by having niche separation to avoid inter- and intra-specific competition within the same habitat. Ecological separation can be in the form of different feeding guilds, niche separation by stratification and different utilisation strategies by being diurnal or nocturnal. For example, vertebrate fauna ( birds and

mammals 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 o ...

) can be defined into six communities based on vertical stratification of the rainforest. First, the small mammals and birds use the forest ground floor and underground. Second, the large herbivores and carnivorous animals range the ground floor of the forest searching for food, shelter and breed. Third,

omnivorous An omnivore () is an animal that has the ability to eat and survive on both plant and animal matter. Obtaining energy and nutrients from plant and animal matter, omnivores digest carbohydrates, protein, fat, and fiber, and metabolize the nut ...

and carnivorous mammals range up and down tree trunk from forest floor to the canopy level. Fourth, are mainly volant mammals such as bats and birds using the middle canopy. Fifth, are top canopy birds and mammals that feed on leaves, fruits, nectar and insects. Sixth, are the fast flying birds and

bat Bats are mammals of the order Chiroptera.''cheir'', "hand" and πτερόν''pteron'', "wing". With their forelimbs adapted as wings, they are the only mammals capable of true and sustained flight. Bats are more agile in flight than most ...

s using the above canopy area.

Invertebrates

There are 639 species of ants, 81 genera and 8 subfamilies of the Formicidae in Poring Sabah.

Vertebrates

Fish

There are 394 species of freshwater fish and 149 are endemic to Borneo.

Amphibians

White-lipped Frog (Hylarana raniceps) (6748201045)

There are at least 180 species of amphibians. One notable species is the

Bornean flat-headed frog The Bornean flat-headed frog (''Barbourula kalimantanensis'') is a species of frog in the family Bombinatoridae. Although many salamanders are lungless, the Bornean flat-headed frog is the first frog known to have no lungs. Djoko Iskandar, an In ...

, ''Barbourula kalimantanensis''. This

frog A frog is any member of a diverse and largely carnivorous group of short-bodied, tailless amphibians composing the order Anura (ανοὐρά, literally ''without tail'' in Ancient Greek). The oldest fossil "proto-frog" ''Triadobatrachus'' is ...

, found in cold, fast-flowing mountain streams, is the only known lungless frog.

Reptiles

105 species of lizards, in 35 genera from nine families, are now known from Borneo. The

reticulated python The reticulated python (''Malayopython reticulatus'') is a python species native to South and Southeast Asia. It is the world's longest snake, and is among the three heaviest. It is listed as least concern on the IUCN Red List because of its w ...

is the largest python in the world, and the longest snake in the world. This reptile can have a size of 6 m or more. The longer snakes have a size of ten meters.

Birds

There are about 600 species of birds and 37 are

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 else ...

to Borneo

Mammals

The historical records of European association with Borneo and its fauna were compiled by Lord Medway that was published in 1977 by the Malaysian Branch of the Royal Asiatic Society. There are 288 species of terrestrial mammals in Borneo which is dominated by the chiroptera (102 species of bats) and rodentia (61 species of rats and mice), and 44 species are endemic to the island. There have also been 91 species of

marine mammals Marine mammals are aquatic mammals that rely on the ocean and other marine ecosystems for their existence. They include animals such as seals, whales, manatees, sea otters and polar bears. They are an informal group, unified only by their re ...

recorded within the territorial boundaries of Malaysia, Indonesia and Brunei.

Impact of deforestation on fauna

With the rapid and massive deforestation in Borneo and resulting destruction of habitats many species are

endangered An endangered species is a species that is very likely to become extinct in the near future, either worldwide or in a particular political jurisdiction. Endangered species may be at risk due to factors such as habitat loss, poaching and in ...

, such as the Bornean orangutan, or critically endangered, such as the

Borneo elephant The Borneo elephant, also called the Bornean elephant or the Borneo pygmy elephant, is a subspecies of Asian elephant ''(Elephas maximus)'' that inhabits northeastern Borneo, in Indonesia and Malaysia. Its origin remains the subject of debate. A d ...

References

* MacKinnon K, Hatta G, Halim H, Mangalik A.1998. ''The ecology of Kalimantan''. Oxford University Press, London. * Mayr. E. 1944. Wallace’s line in the light of recent zoological studies. Quarterly Review of Biology 19:1-14. * Medway L. 1971. The Quaternary mammals of Malesia: a review. In Quaternary era in Malaysia. P. Ashton and M. Ashton (eds). * Medway L. 1977. Mammals of Borneo: field keys and an annotated checklist. Monographs of the Malayan Branch of the Royal Asiatic Society No.7. Kuala Lumpur.

External links

A guide to the lizards of Borneo

Crocodiles and Turtles of Borneo
;General
Mammal Species of the World

Tree of Life
{{Borneo * * . Natural history of Brunei Natural history of Indonesia Environment of Malaysia