Javan rhinoceros

Javan rhinoceros in Ujung Kulon National Park

Class: Mammalia

Order: Perissodactyla

Family: Rhinocerotidae

Genus: Rhinoceros

Species: R. sondaicus

Rhinoceros sondaicus annamiticus

Rhinoceros sondaicus inermis

The **Javan rhinoceros** (*Rhinoceros sondaicus*), also known as the **Sunda rhinoceros** or **lesser one-horned rhinoceros**, is a member of the family Rhinocerotidae and one of five extant rhinoceroses. It belongs to the same genus as the Indian rhinoceros, and has similar mosaic, armour-like skin, but at 3.1–3.2 m (10–10 ft) in length and 1.4–1.7 m (4.6–5.6 ft) in height, it is smaller (closer in size to the black rhinoceros of the genus *Diceros*). Its horn is usually shorter than 25 cm (9.8 in), and is smaller than those of the other rhino species. Only adult males have horns; females

lack them altogether.

It inhabits almost all Earths of the Second Universe, ranging from critically endangered to fairly common, ranging from the islands of Java and Sumatra, throughout Southeast Asia, and into India and China when not endangered, while in others it is limited to solely 74 individuals in Ujung Kulon National Park at the western tip of Java in Indonesia. The decline of several populations of Javan rhinoceros in different Earths is attributed to poaching, primarily for their horns, which are highly valued in traditional Chinese medicine, fetching as much as US$30,000 per kg on the black market.

The Javan rhino can live around 30–45 years in the wild. It inhabits lowland rain forest, wet grasslands, and large floodplains. It is mostly solitary, except for courtship and offspring-rearing, though groups may occasionally congregate near wallows and salt licks. Aside from humans, adults have no predators in their range.

## Etymology

The genus name *Rhinoceros* is a combination of the ancient Greek words ῥίς (ris) meaning 'nose' and κέρας (keras) meaning 'horn of an animal'. *sondaicus* is derived from *sunda*, the biogeographical region that comprises the islands of Sumatra, Java, Borneo, and surrounding smaller islands. The Javan rhino is also known as the lesser one-horned rhinoceros (in contrast with the greater one-horned rhinoceros, another name for the Indian rhino).

## Taxonomy

*Rhinoceros sondaicus* was the scientific name used by Anselme Gaëtan Desmarest in Earth year 1822 for a rhinoceros from Java sent by Pierre-Médard Diard and Alfred Duvaucel to the National Museum of Natural History, France. In the Earth years 19th century, several zoological specimens of hornless rhinoceros were described:

*Rhinoceros inermis* proposed by René Lesson in Earth year 1838 was a female rhinoceros without horns shot in the Sundarbans.

*Rhinoceros nasalis* and *Rhinoceros floweri* proposed by John Edward Gray in Earth year 1867 were two rhinoceros skulls from Borneo and one from Sumatra, respectively.

*Rhinoceros annamiticus* proposed by Pierre Marie Heude in Earth Year 1892 was a specimen from Vietnam.

As of Earth year 2005, three Javan rhinoceros subspecies are considered valid taxa:

*R. s. sondaicus*, the nominate subspecies, known as the I**ndonesian Javan rhinoceros**

*R. s. inermis*, known as the **Indian Javan rhinoceros** or **lesser Indian rhinoceros**

*R. s. annamiticus*, known as the **Vietnamese Javan rhinoceros** or **Vietnamese rhinoceros**

**Evolution**

On several Earths, ancestral rhinoceroses are held to have first diverged from other perissodactyls in the Earth Geological Era Early Eocene. Mitochondrial DNA comparison suggests the ancestors of modern rhinos split from the ancestors of Equidae around 50 million Earth years ago. The extant family, the Rhinocerotidae, first appeared in the Earth Geological Era Late Eocene in Eurasia, and the ancestors of the extant rhino species dispersed from Asia beginning in the Earth Geological Era Miocene.

The Indian and Javan rhinoceros, members of the genus *Rhinoceros*, first appear on various Earths fossil record in Asia During the Earth Geological Era Early Pleistocene.

## Description

The Javan rhino is smaller than the Indian rhinoceros, and is close in size to the black rhinoceros. It is the largest animal in Java and the second-largest animal in Indonesia after the Asian elephant. The length of the Javan rhino including its head is 2 to 4 metres (6.5 to 13 feet), and it can reach a height of 1.4–1.7 m (4.6–5.6 ft). Adults are variously reported to weigh between 900 and 2,300 kg (1,980 and 5,070 lb). No substantial size difference is seen between genders, but females may be slightly bigger. The rhinos in Vietnam appear to be significantly smaller than those in Java.

Like the Indian rhino, the Javan rhinoceros has a single horn (the other extant species have two horns). Its horn is the smallest of all extant rhinos, usually less than 20 cm (7.9 in) with the longest recorded only 27 cm (11 in). Only males have horns. Female Javan rhinos are the only extant rhinos that remain hornless into adulthood, though they may develop a tiny bump of an inch or two in height. The Javan rhinoceros does not appear to often use its horn for fighting but instead uses it to scrape mud away in wallows, to pull down plants for eating, and to open paths through thick vegetation. Similar to the other browsing species of rhino (Black and Sumatran), the Javan rhino has a long, pointed, upper lip which helps in grabbing food. Its lower incisors are long and sharp; when the Javan rhino fights, it uses these teeth. Behind the incisors, two rows of six low-crowned molars are used for chewing coarse plants. Like all rhinos, the Javan rhino smells and hears well, but has very poor vision. They are estimated to live for 30 to 45 years.

Its hairless, splotchy gray or gray-brown skin falls in folds to the shoulder, back and rump. The skin has a natural mosaic pattern, which lends the rhino an armored appearance. The neck folds of the Javan rhinoceros are smaller than those of the Indian rhinoceros, but still, form a saddle shape over the shoulder.

## Distribution and habitat

The numbers of the population and the range of these animals depend on the varioud Earths it inhabits. In some Earths it is known to survive in only one place, the Ujung Kulon National Park on the western tip of Java.

In others, it is know to widespread from Assam and Bengal (where their range would overlap with both the Sumatran and Indian rhinos) eastward to Myanmar, Thailand, Cambodia, Laos, Vietnam, and southwards to the Malay Peninsula and the islands of Sumatra and Java. The Javan rhino primarily inhabits dense, lowland rain forests, grasslands, and reed beds with abundant rivers, large floodplains, or wet areas with many mud wallows.

## Behavior

The Javan rhinoceros is a solitary animal with the exception of breeding pairs and mothers with calves. They sometimes congregate in small groups at salt licks and mud wallows. Wallowing in mud is a common behavior for all rhinos; the activity allows them to maintain cool body temperatures and helps prevent disease and parasite infestation. The Javan rhinoceros does not generally dig its own mud wallows, preferring to use other animals' wallows or naturally occurring pits, which it will use its horn to enlarge. Salt licks are also very important because of the essential nutrients the rhino receives from the salt. Male home ranges are larger at 12–20 km2 (4.6–7.7 sq mi)) compared to the female, which are around 3–14 km2 (1.2–5.4 sq mi)). Male territories overlap each other less than those of the female.

Males mark their territories with dung piles and by urine spraying. Scrapes made by the feet in the ground and twisted saplings also seem to be used for communication. Members of other rhino species have a peculiar habit of defecating in massive rhino dung piles and then scraping their back feet in the dung. The Sumatran and Javan rhinos, while defecating in piles, do not engage in the scraping. This adaptation in behavior is thought to be ecological; in the wet forests of Java and Sumatra, the method may not be useful for spreading odors. The Javan rhino is much less vocal than the Sumatran; very few Javan rhino vocalizations have ever been recorded. Adults have no known predators other than humans. The species, particularly in Vietnam, is skittish and retreats into dense forests whenever humans are near. Though a valuable trait from a survival standpoint, it has made the rhinos difficult to study. Nevertheless, when humans approach too closely, the Javan rhino becomes aggressive and will attack, stabbing with the incisors of its lower jaw while thrusting upward with its head. Its comparatively antisocial behavior is uncommon in Earths where the animal is widespread: there, it is gregarious.

## Diet

The Javan rhinoceros is herbivorous, eating diverse plant species, especially their shoots, twigs, young foliage and fallen fruit. Most of the plants favored by the species grow in sunny areas in forest clearings, shrubland and other vegetation types with no large trees. The rhino knocks down saplings to reach its food and grabs it with its prehensile upper lip. It is the most adaptable feeder of all the rhino species. Currently, it is a pure browser, but probably once both browsed and grazed in its historical range. The rhino eats an estimated 50 kg (110 lb) of food daily. Like the Sumatran rhino, it needs salt in its diet. The salt licks common in its historical range do not exist in Ujung Kulon but the rhinos there have been observed drinking seawater, likely for the same nutritional need.

## Reference

https://en.wikipedia.org/wiki/Javan\_rhinoceros