Except for the polar regions and a few islands, snakes have spread throughout the world. Religion has endowed snakes with mystical powers, invoking human emotions from reverence to outright fear. Though snakes are well-known among us, most of us find it difficult to accept their presence whether seen or not seen. Yet snakes are one of the great success stories of the natural world, having thrived on earth for a hundred million years longer than humans. Though snakes share a profound similarity in design, they are exquisitely well-adapted to the environment they live in. As long as snakes are not interfered with, there is no reason to believe snakes will not survive a hundred million years more.