From the Jaws blockbusters to Shark Week, we are conditioned to see sharks as terrifying cold-blooded underwater predators. McKeever shows that sharks are evolutionary marvels essential to maintaining a balanced ecosystem. We can learn much from sharks, he argues, and our knowledge about them continues to grow. Here he examines four species: Mako, Tiger, Hammerhead, and Great White. He goes back through time to probe the shark's pre-historic secrets,...