Abruptly removed from Gondwanaland about 160 million years ago and left to its own devices in the Indian Ocean, Madagascar, shaped somewhat like a folded omelet, started developing a natural history all on its own. As with many of the other exotic islands, Madagascar developed its own unique species of animals and birds. Over 80% of the wildlife is unique to the island with much of it amazingly different to anything else on Earth. Some 60% of the mammals, 50% of the birds and 90% of the frogs are endemic. Of the mammals, there are no indigenous cats, dogs, antelope or ungulate species. The reptiles, too, are unique in that there are no poisonous snakes, no agamas and no monitors.