The Megalodon and the Great White Shark

"The oceans were once full of enormous, sharp-toothed carnivores. Megalodon was the king of the sea. Even the biggest dinosaurs fled when they saw its fin break the surface. But megalodon is no more; it went extinct. Its cousin, the great white shark, is still here, but it is endangered. What will happen if these huge fish disappear? Learn about the similarities between megalodon and great whites, and what people are doing to avoid losing another giant predator"--Amazon.com.