Anthropology
Related: About this forumDNA From Neanderthals And Denisovans Found In Cave Floor Sediments
DNA From Neanderthals And Denisovans Found In Cave Floor Sediments
Stephen Luntz
27/04/2017 19:00
Neanderthal and Denisovan DNA has been extracted from sediments in caves they once inhabited, even where we've found no bones. The discovery could transform our knowledge of early human evolution and the branches of humanity that have gone extinct. Given the extreme shortage of Denisovan fossils, the technique could multiply our knowledge of these mysterious peoples many times over.
The capture of DNA from objects where blood or hair was shed has become a staple of TV detective shows, but it's harder than TV makes it look. We've only been collecting Neanderthal DNA from bones for 20 years, resolving the old question of whether Homo sapiens and Neanderthals interbred, and raising a new one of whether Neanderthals were a separate species from us at all.
In this light, extracting DNA that has spent hundreds of thousands of years unprotected by bones, teeth, or amber is an astonishing step forward. Yet this is exactly what has been announced in Science. Using 85 samples from seven suspected Ice Age homes for early humans, a team from a dozen scientific institutions collected DNA from 14,000- to 550,000-year-old sedimentary layers.
Despite the astonishing preservation, most of the DNA extracted from these sediments could not be matched to a specific species. Unsurprisingly, most of what could be identified belonged to microorganisms or animals that were probably prey to the cave's inhabitants. Nevertheless, four of the seven caves studied were confirmed to hold Neanderthal mitochondrial DNA.
More:
http://www.iflscience.com/plants-and-animals/dna-from-neanderthals-and-denisovans-found-in-cave-floor-sediments/all/
Warpy
(113,130 posts)I'd love to know what the Denisovans generally did with their dead, since they don't seem to be in cave burials like other homonins. Only one sample of their DNA has been found, extrracted from one small finger bone. We really have no idea what they looked like, science has never found even a partial skull or long bone. We do know some of their DNA made it to the Tibetan plateau, allowing people to adapt to high altitude living, while another batch is in some of the people of the Asian Pacific Islands.
It's interesting that they've been able to isolate DNA fragments from cave sediments and identify them.
cstanleytech
(26,993 posts)Will be interesting to learn if it pans out and if more are discovered.
Warpy
(113,130 posts)Perhaps now that DNA has been isolated from other cave sediments, they can confirm their species. Or if they dig a little deeper, they might luck out and find a tooth or another fortuitous finger bone.