The oldest DNA ever recovered from an animal is adding new chapters to mammoth life history, going back more than 1 million years. The mammoth DNA was extracted from three molars unearthed in the 1970s from permafrost in northeast Siberia.
Genetic material from ancient mammoth molars found in Siberia handily beats the previous record set by 700,000-year-old DNA from a frozen, fossilized horse (SN: 6/26/13). Some mammoth gene snippets suggest that ancient mammoths already had the traits that allowed them to withstand cold temperatures during later ice ages. What’s more, some hairy behemoths that inhabited North America may have been a hybrid mix between the woolly mammoth and a previously unknown mammoth species, researchers report February 17 in Nature.
Mammoths (Mammuthus sp.) appeared in Africa approximately five million years ago (Ma), and subsequently colonized much of the Northern Hemisphere. Results revealed that Columbian mammoth of North America trace its ancestry to a Middle Pleistocene hybridization between these two lineages, with roughly equal admixture proportions. Finally, we show that the majority of protein-coding changes associated with cold adaptation in woolly mammoths were already present one million years ago. These findings highlight the potential of deep-time palaeogenomics to expand our understanding of speciation and long-term adaptive evolution.
an der Valk et al. Nature. doi: 10.1038/s41586-021-03224-9.