This is Wesley, one of our green iguanas. He's often seen hanging out on the shipwreck's hull and is very a friendly vegetarian. Iguanas have a "third eye," called the parietal eye, which is located on the top of their head. It's a small transparent scale on the top of their head that senses light and dark. It not only regulates their circadian rhythm, but also alerts them to predators. That's why as kids, we could never catch a lizard!