The world’s oldest DNA found in Greenland by Danish researchers with the help of UiT in Norway – NRK Troms and Finnmark
Two million-year-old fragments have been discovered in Greenland in what is a historic research find.
A Danish-led research group, in which Norwegian researchers have also contributed, has found DNA from an entire ecosystem that existed millions of years ago.
The study is published in the journal Nature.
Boundary breaking
In 2021 announced researchers at UiT about the discovery of the world’s oldest DNA. It came from mammoths that lived around a million years ago. Researchers at the University of Tromsø have also contributed to the work with the new DNA find, which is therefore twice as old.
– DNA can be broken down quickly, but we have shown that under the right circumstances we can go further back in time than anyone could have dared to imagine, says Professor Eske Willerslev.
Among other things, he is director of the Lundbeck Foundation GeoGenetics Center at the University of Copenhagen.
The researchers have obtained the DNA from sediments.
Hereditary material from mastodon, tuja, birch, reindeer, geese and more tells about the ecosystem in Greenland two million years ago. Back then, Greenland was a much warmer place.
Professor Inger Greve Alsos at UiT is one of the researchers behind the DNA study.
Photo: UiT – The Arctic University of Norway
Researchers Inger Greve Alsos and Alexandra Rouillard at UiT have participated in studies from the Norwegian side.
– We are constantly pushing the boundaries of what is possible to explore, Alsos tells NRK.
– This is the time when the Arctic began to form, when the cooling of the earth began, says the professor.
It was a climate in northern Greenland at the time, where it must have been warm enough for trees, she says. We are talking about species that you do not associate with northern areas today.
Today, approximately 81 percent of Greenland is covered throughout the year, according to Store norske lexikon.
– There are hardly any bushes this far north today, and certainly not trees, says Alsos.
Can see climate change over time
Alsos and her friends have spent a full five years creating a DNA library of plant species by sequencing plants in the herbarium at Tromsø Museum. By matching two million-year-old DNA against this and other DNA libraries, the researchers were able to reconstruct the ecosystem.
Alsos says that this type of research is the only way scientists have to look at climate change over a longer period of time. In modern times, there is only data that goes back up to a hundred years, she says.
– Here we have a direct insight into the evolution. Ancient DNA is the only way to study long-term effects because it is the only data you have.
She says that in Norway, for example, it took several thousand years before many of the species we know today clearly took root here after the Ice Age.
Researchers have found DNA from an entire ecosystem that is millions of years old in Greenland. The elephant mastodon, reindeer and hare lived there in a climate that was quite different from what we know today.
Illustration: BETH ZAIKEN
– If it was just temperatures that determined, then you should have expected all the species to be there as long as it was warm enough. But it is not like that, she says.
Along with others, this is something she will have to research in the future.
The DNA discovery also showed that mastodons lived in Greenland at this time. The huge elephant animal died out around 10,000 years ago.
The study thus shows that these Ice Age animals spread all the way up to Greenland.
The researchers also found DNA from reindeer, hare, goose and lemur. These are animals that are still found in Greenland today.
Cape Copenhagen in Greenland as it looks today. The contrast to the lush image with mastodon and green plants and trees is great. Today, this place is an arctic desert with low biodiversity.
Illustration: Beth Zaiken
Can be beaten again
The field is only about 20 years old, says Alsos, and there may be more records to come.
It’s whatever exciting things remain to be researched from the last million years, she says.
– Within the professional environment, we don’t really have that much in such old tests. Because we have not shown that it is actually possible to find DNA in them. The vast majority of studies of ancient DNA are less than 50,000 years old.
– I think that we will now look for more places with sediments that are older and see what we can find.