Skulls From 'Pit of Bones' May Hold Evolution Clues

Since 1984, scientists have been carefully removing, assembling, and analyzing thousands of bone fragments from the aptly-named "Pit of Bones" cave in Spain, home to the largest collection of ancient human fossils ever found. Now, they say their analysis of 17 skulls thought to be some 430,000 years old sheds light on the earliest Neanderthals—and, potentially, how humans may have evolved. With thick brows and heavy jaws, but not the larger brain cavities seen in later Neanderthals, the skulls suggest that evolution may have happened in distinct phases, with bigger brains coming after the larger brows and jaws, reports National Geographic.

"If we understand how Neanderthals evolved and what has been going on, exactly, in the course of Neanderthal evolution, then we could say what is special with us, what is different," one scientist tells NPR. While the Neanderthals were evolving their distinct features and bigger brains, early humans were evolving in Africa. Then, some 50,000 years ago, when modern humans reached Europe, they were able to best the similarly large-brained Neanderthals, who ultimately died out. Understanding how these species evolved differently may offer clues as to why the most recently evolved humans were able to, ultimately, conquer the world. (Click to read how modern humans are actually no brainier than Neanderthals.)