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Early human settlements in what is now Alaska closely followed the movements of a female woolly mammoth that lived 14,000 years ago, according to a new study. During its lifetime, the animal ranged about 620 miles (1,000 kilometers) from northwestern Canada to deep Alaska.
This explanation sheds light on the relationship between prehistoric giants and some of the first humans to cross the Bering Land Bridge, and suggests that humans established seasonal hunting camps where woolly mammoths were known to congregate.
Researchers from the United States and Canada have established the link between the two species thanks to a new isotope analysis tool, an ancient tooth and a map of archaeological sites in Alaska. The tooth belonged to a woolly mammoth later named Élmayųujey’eh, or Elma for short. The specimen was discovered in 2009 at the Swan Point archaeological site in central Alaska.
The study began after the arrival at the institution’s Alaska Stable Isotope Facility of a “state-of-the-art,” high-precision instrument that fragments samples to analyze strontium isotopes, said lead author Audrey Rowe, a doctoral student at the University of Alaska Fairbanks. — Chemical signatures that reveal details of an animal’s life.
Rowe’s consultant, Matthew Wooller, used the same method to describe the movements of an adult male mammoth for a paper published in August 2021. Wooller, the study’s senior study author, is a professor and administrator in the university’s School of Fisheries and Ocean Sciences. isotope facility
Strontium is a stable isotope formed by the breakdown of the mineral rubidium, a highly reactive metal. This is a slow process with a half-life of 4 billion years, Rowe said. As rubidium breaks down, it first transforms into radiogenic strontium 87 and years later into stable strontium 86.
Where mammoths roamed, rocks melted into the soil, plants grew, animals ate those plants, and their tusks showed the level of strontium in their diet with each layer of ivory.
Woolly mammoth tusks grew at a consistent daily rate, with the first days of the animal’s life recorded at the tips of the tusks. When a tooth sample is split longitudinally, the layers are clearly visible.
This analysis can then be traced to the mineral and strontium levels of rocks around Alaska to map where Elma wandered.
“The U.S. Geological Survey has done a pretty good job of mapping rocks in Alaska,” Rowe said.
Wooller then suggested that the team overlay local archaeological site locations over Elma’s movements.
“And here,” Rowe said, “there was a lot of overlap between the densest area of archaeological sites in Alaska from the late Pleistocene and right over the areas that our mammoth, Elma, used throughout her life.”
The new isotopic data combine data sets created from radiocarbon and DNA analysis of two related baby mammoths also found at Swan Point to create a more comprehensive picture of life 14,000 years ago.
“He was a young adult in the prime of his life. Its isotopes showed that it was not malnourished and died in the same season as the seasonal hunting camp at Swan Point where the female was found,” Wooller said in a statement.
Other researchers agreed. “This study significantly improves our understanding of mammoth behavior and also provides interesting clues about the interaction between humans and mammoths,” Love Dalén, professor of evolutionary genomics at the Center for Palaeogenetics in Stockholm, Sweden, said via email. Dalén was not involved in the new research.
These explanations may also encourage more scientists to seek new combinations of research tools to advance their understanding of science and history.
“Overall, I think the paper is a great example of how a combination of different molecular tools, such as isotope, DNA and radiocarbon analyses, can provide groundbreaking new insights into prehistory,” Dalén said.
The findings were published Wednesday in the journal Science Advances.
Changing the image of hunter-gatherers
New evidence goes beyond understanding of the early relationship between woolly mammoths and humans.
“(The apple) wandered through the highest concentration of archaeological sites in Alaska,” Rowe said in a statement. “It appears that these early humans were setting up hunting camps in areas frequented by mammoths.”
The research also upended the image that lead researcher Rowe said should come to mind when thinking about each of the species independently.
The study team commissioned natural history illustrator Julius Csotonyi to create a digital image of the two species. The final image features all three woolly mammoths found at the Swan Point site, but instead of depicting humans as aggressive hunters surrounding their prey, Rowe insisted that the artist feature a family instead.
“These people were just like us, but we only see the aggressive hunting times in their lives,” he said. To survive, hunter-gatherers had to use “sophisticated” technology to kill mammals, and this required a lot of skill indeed.
Rowe wanted the image, which features a woman, a man, and children watching mammoths, to show that “these people spend a ton of time teaching their kids how to do everything.”
Jenna Schnuer is a freelance writer, editor, and audio producer based in Anchorage, Alaska, focusing (mostly) on science, art, and travel.
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