2-Million-Year-Old DNA Rewrites Our Understanding of Greenland

Though Greenland is now well known for its glaciers and hard-packed permafrost, the Arctic island was once, in fact, green. It was also filled with wildlife. A new study of DNA — the oldest ever found — shows that.

Climate change is melting Greenland’s ice. When that happens, soil that was once hidden is exposed. Scientists took advantage of the newly-revealed land. They got samples from the soil in northern Greenland. They then took out environmental DNA, or eDNA, from the soil.  

Pure DNA comes from a single source. eDNA is different. It's kind of like a soup of genetic material. eDNA is made up of the hair, spit, waste, and decomposing bodies of plants and animals that once lived in the area. To learn from it, researchers had to isolate the frozen strands. They compared the DNA with those of plants and animals known today.

“It was super exciting when we recovered the DNA that a very, very different ecosystem appeared,” Eske Willerslev said. She co-authored the study. The sample is 2 million years old. It showed that the area had once been home to lots of animals. Willerslev called the discovery “mind-blowing.”

Northern Greenland is currently classified as a polar desert. The eDNA samples suggest that the area was likely a thriving forest a long time ago. Temperatures there were probably 50-65 degrees Fahrenheit warmer than today. The animals lived during a time when temperatures around the world were changing a lot. The study's authors hope the eDNA will show how animals today might adapt to changes in the climate. 

Photo from Reuters.