Black rhinos are not black, and white rhinos may owe their name to a mistranslation
Neither of Africa's rhinos is the colour its name suggests. The black rhino ranges from brown to grey, and the white rhino's name is often traced to a Dutch-derived word for wide, describing its broad lip. The real difference lies in the mouth: one grazes grass, the other plucks twigs with a hooked lip.
The black rhino's pointed upper lip is prehensile, able to grip leaves and branches like a stubby finger, because it is a browser that feeds on shrubs. It carries its head higher than the grass-cropping white rhino, which has a squarer mouth, and it is the smaller of the two. Adults usually weigh between 800 and 1,400 kilograms. Two keratin horns sit on the skull, the front one typically about 50 centimetres long, used for defence, digging up roots and snapping branches.
Some popular beliefs about it do not hold up. Rhinos are often said to see poorly, yet studies put black rhino eyesight at roughly the level of a rabbit's. The oxpeckers that ride on their backs picking off ticks were long held up as a textbook partnership, but newer evidence suggests the birds may also feed on rhino blood, making them closer to parasites.
Even the scientific name involves a mix-up. Carl Linnaeus named the species Rhinoceros bicornis, double-horned rhinoceros, in 1758, probably working from the skull of a one-horned Indian rhino onto which a collector had attached a second horn. Once it became clear that India had only a single-horned species, the name passed to Africa, and in 1911 the Cape of Good Hope was fixed as the reference location.
The species is critically endangered, pressed by poaching and shrinking habitat, and the IUCN estimates 3,142 mature animals remain in the wild. The western subspecies was declared extinct in 2011, and the Chobe form may be down to a single animal in Botswana. Survivors now live only in protected reserves, and conservationists have moved animals across borders to restore lost populations. Rwanda's Akagera National Park, which had lost all its rhinos by 2007, received 18 eastern black rhinos from South Africa in May 2017, and a calf born that September brought the herd to 19.
Source: Black rhinoceros
