Rhinoceros

The hippopotamus (Hippopotamus amphibius), from the greek ἱπποπόταμος ( "horse of the river") is a large mammal erbivoroafricano. It is one of two remaining species of Hippopotamidae family (two more have become extinct in recent times). It was long thought that the family of hippos have originated from the same strain from which, on the one hand, the swine (pigs, wild boars etc.) And, secondly, ruminants (eg, deer and cattle).

 The Indian rhinoceros (Rhinoceros unicornis), also called the greater one-horned rhinoceros and great Indian rhinoceros, is a rhinoceros native to the Indian subcontinent. It is listed as Vulnerable on the IUCN Red List, as populations are fragmented and restricted to less than 20,000 km2 (7,700 sq mi). Moreover, the extent and quality of the rhino's most important habitat, alluvial grassland and riverine forest, is considered to decline due to human and livestock encroachment.

 The Indian rhinoceros once ranged throughout the entire stretch of the Indo-Gangetic Plain, but excessive hunting and agricultural development reduced their range drastically to 11 sites in northern India and southern Nepal. In the early 1990s, between 1,870 and 1,895 rhinos were estimated to have been alive. In 2015, a total of 3,555 Indian rhinoceros are estimated to live in the wild. The Indian rhinoceros has a thick grey-brown skin with pinkish skin folds and a blackhorn. Its upper legs and shoulders are covered in wart-like bumps. It has very little body hair, aside from eyelashes, ear fringes and tail brush. Males have huge neck folds. Its skull is heavy with a basal length above 60 cm (24 in) and an occiput above 19 cm (7.5 in). Its nasal horn is slightly back-curved with a base of about 18.5 cm (7.3 in) by 12 cm (4.7 in) that rapidly narrows until a smooth, even stem part begins about 55 mm (2.2 in) above base. In captive animals, the horn is frequently worn down to a thick knob.

The rhino's single horn is present in both males and females, but not on newborn young. The black horn is pure keratin, like human fingernails, and starts to show after about six years. In most adults, the horn reaches a length of about 25 cm (9.8 in), but has been recorded up to 57.2 cm (22.5 in) in length. 
Among terrestrial land mammals native to Asia, the Indian rhinoceros is second in size only to the Asian elephant. It is also the second-largest living rhinoceros, behind only the white rhinoceros. Males have a head and body length of 368–380 cm (12.07–12.47 ft) with a shoulder height of 170–186 cm (5.58–6.10 ft), while females have a head and body length of 310–340 cm (10.2–11.2 ft) and a shoulder height of 148–173 cm (4.86–5.68 ft). The male, averaging about 2,200 kg (4,900 lb) is heavier than the female, at an average of about 1,600 kg (3,500 lb).