Turtles and tortoises, though related, exhibit key differences. Turtles are primarily aquatic with streamlined shells and webbed feet, suited for swimming and varied diets. Tortoises are land-based, ...

It's a long-held idea that turtles can tuck their heads into their shells when threatened. But is it true? And is this protective trick why turtles the world over have shells today? The answer is that ...