A fully grown bull giraffe is the tallest creature on earth, soaring to a full six metres on its stilt-like legs.  It is also one of the four largest land animals, weighing in at 1,5 tons.   Yet despite its bulk this gentle giant blends almost perfectly with its surroundings, the patchwork hide matching the sun-dappled thorn trees of the African savanna so perfectly that it is possible to walk past an entire herd of giraffe without noticing them.   The giraffe's long neck is a classic example of form being moulded by natural selection:  the taller individuals could eat leaves and shoots that were beyond the reach of shorter giraffe, and therefore enjoyed a larger food supply.   Their ability to feed more easily, and their improved chances of survival in the lean seasons, enabled the taller giraffes to breed more successfully - thus concentrating in the ancestral gene pool those particular genes which made them grow tall.   You are able to view these amazing animals at the Umfolozi, Hluhluwe and Mkutzi Game Reserve in South Africa or at the Etosha Pan in Namibia.