Found 46 animals from the Ice Age in a cave in Northern Norway: "Extremely rare"
A remarkable find from the Ice Age reveals a tundra landscape with sea ice, polar bears, and a rich birdlife.
Sanne Boessenkool took part in excavating thousands of bone fragments from the Arne Qvam Cave in Kjøpsvik. Here during fieldwork in another cave.(Photo: Private)
A cave in Kjøpsvik, Narvik municipality, offers a unique glimpse back into the Ice Age. From its floor, researchers have dug up thousands of bone remains from animals that lived in the area 75,000 years ago.
The remains include more than just reindeer: whales, seals, polar bears, birds, and fish were also found. Together, they reveal what the climate and ecosystem looked like during a milder phase of the Ice Age.
"This is extremely rare and valuable," says Sanne Boessenkool, an expert on prehistoric DNA who took part in the excavation.
When the climate cooled toward the end of the Ice Age, glaciers grew several kilometres thick, stripping the land and leaving it barren. Most traces of ancient animals and plants disappeared.
The soil layers in the Arne Qvam Cave are a rare exception.
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"Unique, even by global standards"
In total, researchers found remains of 46 species and animal groups.
Previously, bones from mammoths and other Ice Age animals have been found in Norway and Scandinavia, but not gathered in one place like this, notes Boessenkool, who is a professor at the University of Oslo.
"It's unique, even by global standards," she says.
Researchers at work during the excavation.(Photo: Trond Klungseth Lødøen)
Discovered bones sticking out
The cave is one of the outlets of the larger Storsteinhola cave system. It was first discovered in the 1990s, when the company Norcem, now Heidelberg, was building a tunnel, Boessenkool explains.
"They came across these deposits where bones were sticking out," she says.
Cave expert Stein Erik Lauritzen was called in. He consulted zoologists, and it became clear that the cave contained bones from multiple animal species.
Nothing more happened until researchers secured funding from the Research Council of Norway for excavations in 2021 and 2022. Led by Trond Klungseth Lødøen of the University Museum in Bergen, the project revealed the wide range of Ice Age animals preserved there.
Sediment layers inside the cave.(Photo: Trond Klungseth Lødøen)
Ptarmigan, polar bear, and blue whale
"What’s most exciting about this study is the overall picture: We get a glimpse of an ecosystem from a distant past we know almost nothing about," says Boessenkool.
The researchers identified 23 bird species, 13 mammals, and 10 types of fish, along with a few small marine animals and a plant.
Most of the birds were seabirds such as ducks and auks, but there were also land-dwellers like cranes, ravens, and rock ptarmigan.
Among the land mammals were arctic fox, hare, and reindeer, but also animals tied to sea ice, including polar bear, walrus, and seal.
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The researchers also found bones from several whale species, among them blue whale and porpoise, as well as fish still common in the north today, such as cod, redfish, and haddock.
"It was incredible how many species we found. That was the most surprising thing for me," says Boessenkool.
The findings were published in the journal PNAS with Samuel J. Walker and Aurélie Boilard as lead authors.
Ice-free areas
The remains also shed light on the landscape and climate 75,000 years ago.
Among the discoveries was the collared lemming, a species never before found in Scandinavia and today only living in Siberia.
"It doesn't live in warm regions, so this area must have been cold at the time," says Boessenkool.
Tooth of a collared lemming.(Photo: Sam Walker)
The presence of seals, polar bears, and walruses indicate that there must have been sea ice nearby. At the same time, researchers found porpoise, which does not like sea ice. They believe this suggests the ice was seasonal.
"Reindeer need wide stretches of land to migrate, so there must have been fairly large ice-free areas," says Boessenkool.
"We also found freshwater fish, which means there must have been freshwater in the area," she adds.
Vertebra from a polar bear.(Photo: Trond Klungseth Lødøen)
Variations within the Ice Age
The researchers envision a tundra landscape, dotted with scattered pine trees and some rivers and lakes.
At sea, ice would have formed during certain periods or seasons. The climate was colder than today – perhaps a bit like present-day Svalbard.
"All these species still exist, if you head a little further north," says Boessenkool.
She thinks many believe Norway was covered by ice throughout the last Ice Age.
"But that's not the case. There were large variations during the Ice Age, with periods of more and less ice," she says.
No remains of extinct Ice Age animals such as mammoths or woolly rhinoceroses were found in the cave. That may be because they didn't live in this coastal landscape. Or it could be that the cave simply does not reflect the full range of animals that once lived here.
Photo from the excavation.(Photo: Trond Klungseth Lødøen)
Bones in tiny fragments
Much of the cave’s bone material was broken into pieces just a few millimetres in size.
"We sifted more than a thousand buckets of sediments and used a lamp with a magnifying lens to extract every single fragment," says Boessenkool.
Some bones were intact enough to be identified by species. For the smaller pieces, the team used DNA barcoding, a method that analyses DNA from mixed bone fragments.
This method detects DNA sequences unique to certain species or animal groups and matches them against a database.
"It was thanks to this method that we were able to identify so many birds and fish," she says.
How did remains ranging from birds to whales end up in one cave?
Predators are the most likely explanation, says Boessenkool. Polar bears and arctic foxes could have carried them into the cave. Water may also have brought in carcasses and bones.
Sand and gravel from the cave were extracted and carefully examined to find bone fragments.(Photo: Aurélie Boilard)
A more detailed picture with new methods
Hanneke Meijer, a palaeontologist and professor at the University of Bergen, finds the research project from the cave in Narvik especially exciting
"I've worked with bone material from several caves in Norway and abroad. One of the biggest challenges is that we often only find tiny fragments of bone, making it very difficult to identify the species," she says.
Meijer explains that the researchers here combined traditional methods with newer and more advanced techniques, such as DNA metabarcoding of prehistoric DNA.
"This technique uses prehistoric DNA to identify fragments that would otherwise be difficult to classify using traditional methods. As a result, we can detect far more species than zooarchaeology alone would allow, giving us a much more detailed picture of animal life in the past," she says.
