Dinosaurs have quite the reputation for being the largest, fiercest predators in life's history. Yet, 40 million years before dinosaurs ruled, Pampaphoneus biccai dominated South America as the biggest and most bloodthirsty meat eater of its time.

Dinosaurs have quite the reputation for being the largest, fiercest predators in life’s history. Yet, 40 million years before dinosaurs ruled, Pampaphoneus biccai dominated South America as the biggest and most bloodthirsty meat eater of its time.