Meet the Harpy Eagle, a real-life monster bird with biology so extreme, it seems pulled from a fantasy novel. Towering up to 3.5 feet tall with a wingspan of 7 feet and legs as thick as a human wrist, ...

But, millions of years ago, gigantic animals were much more common than they are today. Let’s take a look at some of the biggest. This ancient alligator ancestor was a monster of a reptile, reaching ...