Is there an animal which has three eyes?

Surprisingly, there is. This is the tuatara, a reptile which looks like a lizard. In some lizards there is a gland at the front of the brain called a pineal body, shapes like an eye. In most of these lizards, the pineal body is not fully developed, and does nothing at all, but in the tuatara’s case, it is developed fully, and acts as a third eye.