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Sloth bear

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The sloth bear, scientifically known as *Melursus ursinus*, is a unique species of bear native to the Indian subcontinent.

Bear - Melursus ursinus at Bannerghatta National Park 8469
Bear - Melursus ursinus at Bannerghatta National Park 8469

It is also frequently called the Indian bear. This species is classified as myrmecophagous, which means it specializes in eating ants and termites. Because of habitat loss and degradation, the sloth bear is currently listed as vulnerable on the IUCN Red List. It is a highly specialized animal that belongs to its own genus, *Melursus*. This makes it quite different from other members of the bear family, or Ursidae.

Sloth bears have developed specific physical traits to support their insect-heavy diet. They possess long, shaggy black or rusty fur, often with a white Y- or V-shaped mark on the chest. This chest mark may serve as a threat display when the bear encounters tigers.

Sloth bears playing
Sloth bears playing

Their muzzles are thick and long with bulbous snouts and wide nostrils. Most notably, they have long, flexible lower lips and lack upper incisors. This anatomical setup allows them to suck up large numbers of insects. They also have disproportionately large paws equipped with long, sickle-shaped claws. These claws are used to scrape open insect mounds. The bears then use their long, broad palates to suck up the insects. This process creates a loud sucking sound that can be heard from 180 meters away.

There are two distinct subspecies of the sloth bear. The first is the Indian sloth bear, or *M. u. ursinus*, which is the nominate subspecies. It is the most widespread variety and lives in areas like the forests and low hills near the Himalayas.

Sri Lankan sloth bear (Melursus ursinus inornatus) male 3
Sri Lankan sloth bear (Melursus ursinus inornatus) male 3

The second is the Sri Lankan sloth bear, or *M. u. inornatus*. This subspecies is generally smaller than the Indian variety. The Sri Lankan bears often have much shorter body hair. Some individuals may even lack the characteristic white chest mark. While the Indian variety lives in diverse habitats like savannahs and grasslands, the Sri Lankan variety is now restricted to northern and eastern lowlands due to forest conversion for tea and coffee plantations.

Scientists have a long history of naming and studying this species. In 1791, George Shaw named the species *Bradypus ursinus*. Later, in 1793, Meyer named it *Melursus lybius*. In 1817, de Blainville used the name *Ursus labiatus* to highlight the bear's long lips.

Slothbearskulls
Slothbearskulls

Other researchers like Illiger and Tiedemann also provided different scientific names based on the bear's hair and snout shape. These various names reflect the many ways scientists have observed the bear's unique physical features over the centuries.

Evolutionary evidence suggests that sloth bears diverged from ancestral brown bears during the Pleistocene epoch.

Slothbearskulls
Slothbearskulls

Some researchers believe they may have emerged during the Middle Pliocene. Fossilized remains, such as a humerus found in the Kurnool Basin of Andhra Pradesh, are identical to modern sloth bear bones. Additionally, fossilized skulls of *Melursus theobaldi* from the Shivaliks are thought to be an intermediate stage. These fossils show teeth that are intermediate in size between sloth bears and other bears. This supports the theory that the sloth bear evolved through convergent evolution to fill a specific ecological niche for eating insects.

Sloth bears vary significantly in size and weight. In the nominate subspecies, males are typically larger than females. Adult males can reach weights of up to 140 kilograms, while females are often around 100 kilograms.

Sri Lankan sloth bear (Melursus ursinus inornatus) male 6
Sri Lankan sloth bear (Melursus ursinus inornatus) male 6

In Sri Lanka, the bears are even smaller. Some male Sri Lankan bears average only 60 kilograms. This indicates that Sri Lankan populations may be about 30% lighter in body mass than the nominate race. This difference in size between males and females is known as sexual dimorphism.

Life cycles and social behaviors are also quite specific to this species. In India, mating occurs during April, May, and June, with births in December or early January.

Sloth bear cubs by Samad Kottur
Sloth bear cubs by Samad Kottur

In Sri Lanka, breeding can happen throughout the year. Cubs are born blind and begin walking just one month after birth. They often ride on their mother's back for protection until they reach one-third of her size.

MelursusUrsinusFemaleCub
MelursusUrsinusFemaleCub

Mothers use this climbing ability to carry cubs up trees to protect them from predators like leopards or other bears. While they may appear slow, sloth bears are excellent climbers and good swimmers.

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🖼️ Images & Media (11)
File:Bear - Melursus ursinus at Bannerghatta National Park 8469.JPG
Bear - Melursus ursinus at Bannerghatta...
File:Sri Lankan sloth bear (Melursus ursinus inornatus) male 3.jpg
Sri Lankan sloth bear (Melursus ursinus...
File:Slothbearskulls.jpg
Slothbearskulls.jpg
File:Sri Lankan sloth bear (Melursus ursinus inornatus) male 6.jpg
Sri Lankan sloth bear (Melursus ursinus...
File:Sloth bears playing.jpg
Sloth bears playing.jpg
File:SlothBearTree.jpg
SlothBearTree.jpg
File:Sloth bear cubs by Samad Kottur.jpg
Sloth bear cubs by Samad Kottur.jpg
File:MelursusUrsinusFemaleCub.jpg
MelursusUrsinusFemaleCub.jpg
File:A fragile co-existence of between sloth bears and humans at Ratanmahal Sloth Bear Sactuary, Dahod, Gujarat, India.jpg
A fragile co-existence of between sloth...
File:Sloth bear hunt.jpg
Sloth bear hunt.jpg
File:Pushkar-bear and handler.jpg
Pushkar-bear and handler.jpg
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