Overview
- Scientists extracted environmental DNA from fossilized ground‑squirrel coprolites recovered in Yukon permafrost and assembled roughly 18 to 20 complete mitochondrial genomes.
- The genetic material records plants, insects, microbes and large animals, with sequences attributed to woolly mammoths, steppe bison, horses and big‑cat and wolf predators.
- Some samples sit below volcanic‑ash layers that the team used to infer ages up to about 700,000 years, but the authors stress those age estimates and interpretations are still being verified.
- Researchers note coprolites concentrate dietary and environmental material because squirrels cached bones, seeds and plant matter in burrows, but they also warn about risks from contamination, DNA leaching and gaps in reference genomes.
- The team plans further analyses, including an upcoming paper focused on mammoth sequences and public data release, and they caution that thawing permafrost threatens remaining palaeoarchives.