The giraffe (Giraffa camelopardalis) is an African even-toed ungulate mammal, the tallest of all extant land-living animal species, and the largest ruminant.The giraffe is related to other even-toed ungulates, such as deer and cattle, but is placed in a separate family, consisting of only the giraffe and its closest relative, the okapi, and their extinct relatives. Its range extends from chad in central Africa to south Africa.They will drink large quantities of water when available, which enables them to live for extended periods in arid areas.
Giraffes browse on the twigs of trees, preferring trees of the genera acacia, Commiphora and Terminalia, and also eat grass and fruit. The tongue, lips and palate are tough, which allows them to feed on trees with sharp thorns. In South Africa, giraffes feed on all acacias, especially acacia erioloba. A giraffe can eat 65 pounds (29 kg) of leaves and twigs daily, but can survive on just 15 pounds (6.8 kg)A giraffe can clean off bugs (like acacia ants) on its face with its extremely long tongue (about 45 centimeters (18 in).
The giraffe's extreme altitude is a consequence of its extremely elongated neck, which can be over 2 m (7 ft) in length, accounting for nearly half of the giraffe's vertical height. The increase in neck length results from the disproportionate elongation of the cervical vertebrae, rather than the addition of more vertebrae. The cervical vertebrae comprise about 45–50% of the giraffe vertebral column, compared to the 30% typical of similar large ungulates, including the giraffe’s closest extant relative, the okapi. This elongation, which occurs in large part after birth, is a 150% increase in vertebrae length over similar sized animals – in fact, the non-cervical sections of the giraffe vertebral column exhibit identical proportions to those in okapi.