Most of us who have taken an anthropology course are familiar with Neanderthals, early humans, and a few other species of closely related hominids, like Lucy the Australopithecine. While these species are all somewhat different in nature, scientists have been working hard to see where they fit—and how and when they crossed paths—in the grand scheme of evolution.

But the search for the missing links between humans and apes doesn’t stop with these groups. In fact, a discovery inside a cave in China might just offer some new details about some of the other mysterious human-like species that may have once roamed the Earth.

Researchers now believe that these skulls may have belonged to a creature that bred with both Neanderthals and humans, and could be a crucial part of that missing link.

In 2007, scientists uncovered flint tools buried in the sediment inside a Siberian cave that dated back as far as 125,000 years. There was just one issue: they didn’t quite fit with the facts we know about the early human species that once lived in that region.

02-denisovan-skullsLoronet / Flickr

Years later, two ancient skull fragments were discovered in northern China that may hold the answer to the mystery of the tools. Some researchers believe both the skulls and tools belonged to a species called the Denisovans, a mysterious group that once lived in Siberia and East Asia.

The skulls resembled those of ancient humans that were found about 528 miles away, suggesting that Denisovans, early humans, and Neanderthals may have all been members of one large regional group. The find also offered further evidence to help bridge early hominid species.

How crazy is it that there could’ve been yet another species of humans out there? See what researchers say about this new group…

We don’t have many actual pieces of the Denisovans out there, and the connection between those old tools and the skulls has yet to be confirmed, but it’s fascinating all the same. There is still so much that we don’t know!

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