Three mammoth teeth, one and a half million years old, still contained just enough DNA for an unprecedented discovery to be made about this animal: never had such an old genetic material been collected.
After the , the DNA molecules, which make up our genes, break down relatively quickly: this is why it is difficult to piece together the genomes of prehistoric humans tens of thousands of years old – and that is only Step by step as we assemble the pieces of the puzzle that connects us to our Neanderthal and Denisovan cousins less than 100,000 years old. The record so far belonged to a 600,000 to 700,000 years old, collected from a bone .
However, these teeth of three mammoths from the same period have enough still “legible” fragments for one to deduce that there was in Siberia a distinct line of woolly mammoths (), a line of which the mammoths of of () would be the descendants. The results appeared on February 17 in the journal .
Being trapped in permafrost – permanently frozen ground – helped, researchers say. slows down DNA fragmentation. If they are right, however, this narrows the spectrum of possibilities for finding other genomes as old. But it is possible that new technologies will open new doors: in recent years, we have talked about extracting protein sequences from remains 2 to 3 million years old. These sequences provide less information than DNA, but are more resistant to passage of .