The Parson's Chameleon is a species of chameleon from the rainforests of Madagascar. It is one of the largest known species of chameleon in the world, by weight not length. Its name comes from the British physician James Parsons, who made several important investments in the field of medicine. Like all chameleons, it is capable of changing color, which it can use to show its mood or to blend in with its surroundings.