The Serengeti ecosystem is one of the oldest on earth. The essential features of climate, vegetation and fauna have barely changed in the past million years. Early man himself made an appearance in Olduvai Gorge about two million years ago. Some patterns of life, death, adaptation and migration are as old as the hills themselves.

It is the migration for which Serengeti is perhaps most famous. Over a million wildebeest and about 200,000 zebras flow south from the northern hills to the southern plains for the short rains every October and November, and then swirl west and north after the long rains in April, May and June. So strong is the ancient instinct to move that no drought, gorge or crocodile infested river can hold them back.