Homo ergaster, an ancient predecessor of modern humans, had to scavenge to survive. They lived in the elements among the monsters of the day, like the saber-toothed cat. Over time, early humans evolved and developed simple tools, began to communicate, and learned to control their most important tool, fire. 40,000 years ago, Neanderthals were at the top of their form, hunting beasts like the Giant Steppe Bison. The Neanderthals were usurped by an entirely new race of humans, the Cro-Magnons. They adapted and survived when the Neanderthals could not.