"Uncover the mystery of the dinosaur extinction with diagrams, strong photos, and hi/lo text"--

The past is full of mysterious events. How did ancient people build pyramids. What is Stonehenge for? Maybe the explanations for these events are simple ... or

Learn more about extinction and how it affects the world around you.

This study identifies the fall of dinosaurs as the factor that allowed mammals to evolve into the dominant tetrapod form. It refutes the single-cause impact the