7. Dunkleosteus

This was a Late Devonian fish from 358-382 million years ago. It could grow up to 20 feet long, and weigh up to one ton! They are predators at the top of the food chain and are believed to have existed for 70 million years. One distinguishing feature of the Dunkleosteus is that instead of teeth, they have two pairs of sharp bony plates forming a beak-like structure. It took around 20 milliseconds for them to open their mouth and just 50 to 60 milliseconds for a complete snap.