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White rhinoceros -

The white rhino is the largest extant species of rhinoceros. White rhinos consist of two subspecies: the southern white rhino, and the northern white rhino.

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Southern white rhinoceros -

The southern white rhino is the largest land mammal after the elephant. Their range extends across South Africa, Namibia, Botswana, Zimbabwe, Zambia, Kenya, and Uganda.

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Southern white rhinoceros -

Despite the species representing a major conservation success story, having been brought back from the very brink of extinction, the International Union for Conservation of Nature (IUCN) maintains the southern white rhino as Near Threatened on its Red List.

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Northern white rhinoceros -

The northern white rhinoceros is the world's rarest rhino. Sadly, there are only two northern white rhinos left on the planet. Both are female (pictured). The last remaining male died of natural causes in 2018, effectively rendering the entire subspecies extinct.

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Northern white rhinoceros -

Fatu (front) and Najin, the only two remaining northern white rhinos, are pictured grazing in their paddock at the Ol Pejeta Conservancy in Nanyuki, Kenya.

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Black rhinoceros -

One of two African species of rhinoceros, the black rhino is native to eastern and southern pockets of the continent.

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Black rhinoceros -

The black rhino once roamed most of sub-Saharan Africa. Today, however, the animal is listed as Critically Endangered by the IUCN. A subspecies, meanwhile, the south-western black rhinoceros, is listed as Near Threatened.

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Indian rhinoceros -

A rhinoceros species native to the Indian subcontinent, the Indian rhino is registered as Vulnerable on the IUCN Red List.

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Indian rhinoceros -

The Indian rhino is also known as the greater one-horned rhinoceros (the species, together with the Javan rhino, only has one horn, whereas all the other rhino species have two horns).

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Javan rhinoceros -

With a population of approximately 66 in Ujung Kulon National Park—a UNESCO World Heritage Site—located at the western tip of Java in Indonesia, the Javan rhinoceros is one of the rarest animals in the world. It's listed as Critically Endangered by the IUCN.

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Javan rhinoceros -

Javan rhinos are still breeding in the wild, but their rarity means they are the least studied of all rhinoceros species.

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Sumatran rhinoceros -

Also registered as Critically Endangered by the IUCN, the Sumatran rhinoceros is represented by just five substantial populations in the wild: four in Sumatra, and one in Borneo. Its total population in the wild numbers perhaps less than 50 mature individuals.

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Sumatran rhinoceros -

The smallest rhino species, the Sumatran rhinoceros once roamed rainforests, swamps, and cloud forests in India, Bhutan, Bangladesh, Myanmar, Laos, Thailand, Malaysia, Indonesia, and southwestern China.

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Weighty issues -

A white rhino can weigh up to 3,500 kg (7,716 lbs). A Sumatran rhino, the smallest species, still weighs in at an average 600 kg (1,322 lbs).

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Not quite black or white -

Both the white rhino and black rhino are in fact gray in color. Interestingly, the white rhino is said to have been called as such from the Afrikaans word for wide (wyd), referring to its wide, square lip. Early English-speaking settlers in South Africa misinterpreted this for "white."

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Keeping it in the family -

Male rhinos are called "bulls" and females are called "cows." Their young are "calves." Females tend to be more sociable.

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What's in a name? -

A group of rhinos is called a "crash." And what about the name rhinoceros itself? It actually means "nose horn."

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Rhino horn -

Rhino horn is made up of keratin—the same protein that forms the basis of our hair and nails. Horns grow continuously during the animal's lifetime.

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Size matters -

According to the International Rhino Foundation, the longest rhino horn recorded to date is a 150 cm (59 in), belonging to a white rhino.

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Poor vision -

Rhino eyes are on the side of the head, which means they don't have binocular vision. Furthermore, they are known to have poor eyesight. They are also color blind.

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Excellent hearing and smell -

Rhinos make up for their visionary deficiencies with a fantastic sense of smell and super sharp hearing.

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Vocalization -

Rhinos communicate with each other through a variety of vocalizations. During confrontations, they growl and make "trumpet calls." The animals express anger by snorting, and scream when scared. Alarm calls are sneeze-like in sound.

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Communication -

Rhinos also communicate through their dung and urine. When a rhino defecates in the same spot as other rhinos, an area known as a  communal latrine, they can smell the poo and pee of others and identify who's in the area.

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Mud, glorious mud! -

As do elephants and hippos, rhinos love mud. As well as keeping them cool, rolling around in mud gives them a protective coat against insect bites. Mud also helps rid them of parasites.

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Taking to water -

Asian rhinoceros are excellent swimmers. Indian, Javan, and Sumatran rhinos regularly take to rivers, either for a dip or when patrolling territory.

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Decimated population -

At the turn of the 20th century, some 500,000 rhinoceros could be found roaming across Africa and Asia. Today, less than 27,000 rhinos remain in the wild, according to estimates published in the annual report by the International Rhino Foundation.

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Dreadful misconception -

Poaching for rhino horn and habitat loss has decimated the rhino population. Rhino horn is used as an ingredient in traditional Asian medicine under the misconception that the keratin has medicinal properties that can cure a variety of ailments, anything from hangovers to erectile dysfunction.

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No medical value -

The simple truth is that rhino horn has no proven medicinal value in humans whatsoever. Meanwhile, the illegal trade in the material is threatening the existence of all five rhino species.

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The gold standard in poaching -

Indeed, over 7,100 African rhinos have been killed by poaching in the last 10 years, according to the World Wildlife Fund. That's around two animals shot a day! And it's a lucrative trade. The unlawful practice has kept the value of rhino horn on the black market higher than gold, making the hunt well worth the risk for poachers.

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Help keep the five alive -

By supporting organizations such as the World Wildlife Fund, International Rhino Foundation, and Fauna & Flora, you can help fund conservation programs and initiatives (pictured) that aim to keep the five alive.

Sources: (World Wildlife Fund) (International Rhino Foundation) (Fauna & Flora) (National Geographic) (IUCN)

See also: Earth's best destinations to see wildlife

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