Scientists have discovered the oldest DNA in Greenland, which is two million years old

Scientists discovered the oldest DNA (genetic material) in northern Greenland, two million years ago, in sediment samples, and it was released on Wednesday.

According to a study published in the scientific journal Nature, microscopic fragments of environmental DNA (from animals, plants, and microorganisms) were found in Pleistocene sediments in northern Greenland, in 41 incomplete but usable samples that were hidden in clay and quartz.

All types of organisms leave traces in the environment (soil, water, atmosphere) from which DNA (environmental DNA) can be extracted and used to identify them.

Thanks to cutting-edge technology, scientists have discovered that the microscopic fragments of DNA in question are a million years older than the previous record of DNA extracted from the bones of a Siberian mammoth.

Scientists hope that the results obtained will help predict the long-term environmental impact of the current global warming, as plants and animals that left traces of their DNA in the environment survived during a period of significant climate change.

The analyzed samples were taken from the geological formation of Kap Kobenhavn, an approximately 100-meter-thick sediment located at the mouth of a strait in the Arctic Ocean, the northernmost point of Greenland (the Danish island). Currently, the area is a polar desert. However, millions of years ago it was teeming with flora and fauna.

The climate in Greenland at that time ranged between icy and temperate and was between 10 and 17 °C warmer than the climate in Greenland today, with sediments accumulating over tens of thousands of years before temperatures cooled and solidified. Discoveries made in “permafrost” (permanently frozen ground).

The researchers discovered traces of animals, plants, and microorganisms, including fungi, bacteria, birch trees, poplars, reindeer, lemmings (small rodents), and hares, and that a mastodon, an Ice Age mammal, whose fossils were found in North America as well. It reached Greenland before it became extinct.

The work, which began in 2006 and involved scientists from the United Kingdom, Denmark, France, Sweden, Norway, the United States and Germany, compared each fragment of DNA with vast libraries of DNA extracted from animals, plants and modern microorganisms.

Some DNA fragments were easy to classify as ancestral to current species, others could only be associated at the genus level, and some came from species that were impossible to locate in the DNA repositories of surviving animals, plants, and microorganisms.

The two-million-year-old samples gave scientists an idea of ​​a hitherto unknown stage in the evolution of the DNA of a number of species.