Scientists have discovered two million-year-old DNA (genetic material) in sediment samples in northern Greenland, it was published on Wednesday.
According to a study published in the scientific journal Nature, microscopic fragments of environmental DNA (from animals, plants and microbes) were found in incomplete but usable samples hidden in clay and quartz in glacial sediments in northern Greenland.
All species 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 tiny fragments of DNA in question are a million years older than the previous record of DNA extracted from the bone of a Siberian mammoth (an extinct animal).
Scientists hope that the obtained results will help predict the long-term ecological impact of current global warming, because plants and animals that left traces of their DNA in the environment survived during significant climate change.
The analyzed samples were taken from the nearly 100-meter-thick Cup Copenhagen Geological Formation located at the mouth of a fjord in the Arctic Ocean, the northernmost point of Greenland (Danish Island). Currently, the region is a polar desert. However, millions of years ago it was teeming with plants and animals.
Greenland’s climate at that time was between glacial and subtropical and was 10ºC to 17ºC warmer than the climate in Greenland today, as sediment accumulated tens of thousands of years ago, cooling temperatures and consolidating temperatures. Permanently frozen ground found in ‘permafrost’).
Researchers have found traces of animals, plants and microbes, including fungi, bacteria, birch trees, poplars, reindeer, lemmings (small rodents) and rabbits, and the mastodon, an Ice Age mammal whose fossils have been found in North America. reached Greenland before extinction.
The work, which began in 2006 and involved scientists from the United Kingdom, Denmark, France, Sweden, Norway, the United States and Germany, compared each piece of DNA to extensive libraries of DNA extracted from modern animals, plants and microbes.
Some DNA fragments were easy to classify as progenitors of current species, others were related only at the genus level, and some came from organisms that could not be found in the DNA repositories of organisms, plants, and microbes.
The two-million-year-old samples gave scientists an idea of a previously unknown stage in the DNA evolution of many species.