That is not a tree, it is a mammoth tusk and is over a million years old: the story of one of the oldest DNAs that we have been able to recover.
East of the Lena River and the Angara Shield, Russia still has six million kilometers that will die to the Bering Strait and that once were the vast domains of the Mammoth. Love Dalén and his team know this well because they have been collecting fossils of these animals for years throughout the north-eastern region of Siberia. His obsession has a name: ancient DNA.
And is that ancient DNA is a fascinating doorway to Earth’s biological evolution. A narrow door, tiny and, of course, darn hard to find. Above all, because there are processes such as speciation (the formation of new species) that spread through history in a much longer way than the DNA that we have been able to recover and sequence can take us.
All the teeth of the past
In the case of the mammoth, the oldest samples dated from about 780,000 ago. However, Dalén’s team just sprayed that brand and informan and ‘Nature’ from DNA recovery from molars of three mammoth specimens from the early and middle Pleistocene. That is, in at least two cases, more than a million years ago.
DNA-based age estimates (obtained using data from the mitochondrial genome) suggest that Krestovka’s specimen is approximately 1.65 million years old; that of Adycha, 1.34 million years, and that of Chukochya, 0.87 million years. But the most interesting is not that.
Most interestingly, thanks to these samples, the researchers believe that there were two mammoth lineages in eastern Siberia during that time. Adycha and Chukochya are “grandparents” of the famous woolly mammoth, while the Krestovka mammoth is something completely different and unknown: a totally new lineage for us. Of course, by searching the databases, the authors found similarities with the mammoths of North America and are convinced that Krestovka’s lineage was the one that crossed the Bering Strait and conquered the new world.
In other words, the most interesting thing is to see live and direct how ancient DNA can help us fill in the gaps in life’s story and, by extension, our own story.