Turtles are cool creatures, cold blooded reptiles who have hard shells to protect them from predators. - Most turtles can hide their heads and entire bodies in their shells when attacked. - Turtles have been around for 215 million years. - Sea turtles drink salt water because of glands that can remove salt from saltwater. - The largest turtle species are the leatherback sea turtles that can weigh up to 900 kilograms (2000 lbs).