Scientists Finding Ancient Human DNA in Cave Dirt

(Photo: Sergei Zelensky/The Russian Academy of Sciences)

               Until only recently, the only way to study the genes of ancient ancestors of humans, such as Neanderthals and Denisovans was through fossils. With new technological advancements, scientists are now able to study ancient genes from sediment. This is advantageous because fossils are so scarce and very difficult to discover. In the words of geneticist Adam Siepel, “It’s a bit like discovering that you can extract gold dust from thin air.”

               On the lack of realistic ability to find fossils, evolutionary geneticist Henry Poinar, adds, “In a lot of cases, you can get bones but not enough. If you just have one small piece of bone from one site, curators do not want you to grind it up.” A group of researchers in Colorado spent twenty years sifting through tons of dirt in uncovering bones, teeth, and skin of twenty animal species. A different group of scientists took one tablespoon of dirt from the same cave and within two weeks time, they were able to identify sixteen animal species who had lived there.

               Knowing that DNA sticks to minerals and decayed plants in soil, scientists were unsure if it would be possible to gather genes from tens of thousands of years ago. Recently, a group of German researcher extracted between 5,000 and 8.2 million DNA fragments from dirt in caves of Eurasia, a fraction of which belong to prehistoric humans at least 14,000 years ago. With this new technology and information, scientists will be able to learn more about the lives of ancient humans than ever before. According Dr. Reich, these findings suggest a possibility of uncovering DNA in open air sites as well, and in his words, “That would be a magical thing to do.”