Scientists reconstructed ancient DNA from samples found in soil for the first time, in a development that is set to significantly advance the study of evolution. Their findings are published in the journal Current Biology.
The findings, which have been described as the “moon landings of genomics,” mean that researchers will no longer have to rely solely on finding and testing ancient fossils of bone or teeth to determine genetic ancestry.
A team of scientists, led by Professor Eske Willerslev of the University of Cambridge’s Department of Zoology, recreated the genomes of animals, plants, and bacteria from microscopic fragments of DNA found in the Chiquihuite Cave in the Astillero Mountains of North-Western Mexico.
Their work constitutes the first time environmental DNA has been sequenced from soil and sediment, which included the ancient DNA profile of a Stone Age American black bear.
By sampling feces and urine droplets from an ancestor of the American black bear, the scientists recreated the entire genetic code of two species of the animal — the Stone Age American black bear, and a short-faced bear called Arctodus simus that died out 12,000 years ago.
Soil samples used to reconstruct genomes for the first time
By reconstructing DNA from highly fragmented samples found in soil, the researchers opened up a whole host of possibilities for future investigations into ancient settlements.
“When an animal or a human urinates or defecates, cells from the organism are also excreted. We can detect the DNA fragments from these cells in the soil samples and have now used these to reconstruct genomes for the first time,” Professor Willerslev explained in a Cambridge University press release. “We have shown that hair, urine, and feces all provide genetic material which, in the right conditions, can survive for much longer than 10,000 years.”
Willerslev said that the new findings could lead to whole new areas of investigation into climate change and the evolution of species, as fossils are no longer a requirement. The team of researchers explained that tests could now reveal never-before-detected insights into a large number of Stone Age settlements worldwide.
“Imagine the stories those traces could tell,” Willerslev said. “It’s a little insane — but also fascinating — to think that, back in the Stone Age, these bears urinated and defecated in the Chiquihuite Cave and left us the traces we’re able to analyze today.”
Discounting recent false claims that Neuralink has the technology to build Jurassic Park, this is one of the most impressive recent developments in genomics and is likely to lead to a host of new findings about our past and the evolution of life on our planet.