This Wednesday, Jan. 8, 2003 file photo shows a reconstructed Neanderthal skeleton, right, and a modern human skeleton on display at the Museum of Natural History in New York.What makes humans unique? Scientists have taken another step toward solving an enduring mystery with a new tool that may allow for more precise comparisons between the DNA of modern humans and that of our extinct ancestors. Just 7% of our genome is uniquely shared with other humans, and not shared by other early ancestors, according to a study published Friday in the journal Science Advances. "That's a pretty small percentage," said...
