10 million years ago, turtles could eat you with a single bite. Meet Stupendemys geographicus, the largest freshwater turtle that ever existed. This prehistoric giant roamed South America between 13 and 5 million years ago during the Middle Miocene to early Pliocene epochs. Its shell measured over 2 meters (6.5 feet) long—about the size of a small car. Male specimens had bony horns growing from the front edges of their shells, likely used for defense or combat with rivals. Fossils show that thei