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More than 17,000 years ago, a woolly mammoth known today as Kik traveled far and wide in Alaska during its 28-year life.

When Kik was young, he spent most of his time in the interior of Alaska, in a less mountainous region. Then, by the time he was 15, his movement patterns changed and he spent much more time north, where the Arctic Wildlife Refuge and National Oil Reserve are today.

In some years, Kik migrated with the seasons. In other years, it remained largely in the same area all year.

During the last few years of his life, his movement slowed and he was confined to a smaller area above the Arctic Circle. Kik was still middle-aged for a mammoth when he died at 28.

This map that Kik traveled throughout his life was put together by examining the signatures of the elements locked in one of his eight-foot-long curved tusks, and provides insight into these furry, elephant-like mammals.

“This is a better understanding of how they behave, what media they use,” said Matthew Wooller, director of the stable isotope facility at the University of Alaska at Fairbanks and lead author of a paper published Thursday by the journal Science and describing the findings. .

The data may also play a role in the debate about the death of the woolly mammoth after the end of the last ice age. Did early humans hunt them to extinction? Was it a changing climate that they couldn’t adapt to?

Dr. “Our work touches on that a little bit by filling in the puzzle,” Wooller said. “When trying to understand the causes of an extinction, you need to know a little more about the behavior and ecology of the organisms involved.”

Most mammoths disappeared about 10,000 years ago – very recently, on evolutionary and geological time scales – and not all fossil remains turned into rock. This allows DNA to be extracted and sequenced from bones, which helps answer broad questions like how closely related Alaskan mammoths might be to those in Siberia.

But genetic information tells very little about how a mammoth lived. Did it migrate with the seasons? Did he spend his youth in one region and his adulthood in another?

Dr. Wooller and colleagues were able to answer these questions by examining the isotope signatures in Kik’s tooth.

“If you took all these curved lines and straightened them out, it could have gone around the Earth almost twice,” he said.

The findings impressed Brooke Crowley, a professor of geology and anthropology at the University of Cincinnati, who was not involved in the study.

“It’s pretty amazing how much can be learned from tiny little bits of material from an extinct animal,” he said in an email. “I was particularly impressed with the way the authors were able to track the movements of this individual mammoth throughout its entire life.”

Dr. Wooller and colleagues took advantage of the fact that the teeth were growing layer by layer—a structure resembling stacked ice cream cones—to re-determine where Kik is. When Kik was a baby, the tip of the tooth popped out.

Pointing to the base of the tooth during a video call, Dr. “This surface here is basically the day he died,” Wooller said.

In between, he actually had a record of every day of his life. “If you zoom in with the microscope,” said Dr. Wooller, “you can see individual diary tapes.”

Also, Alaska has a rich diversity of rock formations, each with distinct mineralogical fingerprints reflected in the plants that grow there. The researchers focused on strontium, an element that comes in four stable versions, or isotopes.

So every day, Kik chewed grass containing strontium levels that mirrored those of the underlying rocks, and the same strontium levels were incorporated into the layer at the base of the tooth that day.

Similar analysis techniques have been applied to teeth. But using them with a long, bulky, curved tooth was more difficult. Brute force had to be carefully applied to reach the microscope tooth layers.

Of the hundreds of mammoth tusks found, Kik’s tusks were well-suited for this research, excavated in 2010 near a river that gave it its nickname. They were in good condition and the two were rescued together.

Dr. “It’s pretty rare to find a pair of teeth,” Wooller said.

That, and the presence of fragments of his skeleton, gave scientists confidence that Kik died on the spot, and that the remains were not pushed there by a glacier or a flood. The bones allowed them to perform a genetic analysis that confirmed it was a male mammoth. Having two teeth made them feel less remorseful for splitting one in two.

“Pretty heavy,” said Dr. Wooller. “And you think a lot about it. You practice before you commit.”

They cut out what they called “no data”, where there is no recorded information about where and when it was found and therefore of little use scientifically. First they cut a small channel along one edge. Then they marked the points in the middle of the tooth. With a large band saw—”Tall as a human,” said Dr. Wooller – they cut the tooth in half, carefully guiding the blade between the channel and the marks on the other side.

Then they cut Kik’s tooth.

Dr. “It took us most of the day to do it just to split that thing up,” Wooller said. “Six of us and then a very, very large band saw.”

“Even above the noise of the bandsaw, what was frustrating were the sometimes pretty loud pops and cracks,” he said. “We were thinking, ‘Oh, we’re going to destroy this thing. It will disintegrate when we reach the end.’ But it didn’t. It held up really, really great.”

After the female was cut in half, the scientists used a laser to cut blobs along its length for isotope analysis. From there, a computer program compared the strontium levels to a map of what was found in the Alaskan rocks and calculated the most likely path Kik took. The scientists also looked at other elements such as oxygen, nitrogen and carbon, which provide complementary information about ecology.

When Kik died, the world was still on the cusp of the last ice age, but glaciers weren’t flowing over most of Alaska back then. Instead, the environment appears to be dry, cool grasslands, perhaps similar to today’s Mongolian steppes. Dr. “It provided this wonderful environment for mammals to roam,” Wooller said.

Like some modern elephant species, where the young males are expelled from the female herds at age 15 or 16, Kik similarly living a more lonely life.

Dr. “Finding this was a really cool thing,” Wooller said. “In many ways, this was almost exactly the same as some of the behaviors we would see in modern elephants.”

An increase in nitrogen isotopes was a distinctive signature suggesting starvation at the end of life.

Dr. “It’s nice to think we’ve identified not only his movement patterns, but also what probably caused his death,” Wooller said.

As for why Kik was starving, perhaps a drought dried up the landscape or he was injured in a fight, limiting his mobility.

Although Kik has circumnavigated most of Alaska, it appears that it has never traveled west from the land bridge connecting Alaska to Russia. This may indicate that transcontinental transit is not an easy road. Dr. “Some people believe the weather is very, very wet, swampy and dangerous,” Wooller said.

Kate Britton, an archaeologist at the University of Aberdeen in Scotland who was not involved in the research, said scientists should be careful not to predict Kik’s movements to the behavior of woolly mammoths as a species.

He noted that his research, using similar techniques, shows that members of the same modern caribou species behave in different ways depending on where they live. About the daily lives of animals could not be found in their genes.

Dr. “We need this kind of work that gives us this access to this direct information,” Britton said. “We can infer the behavioral ecology of extinct species.”

In his future research, Dr. Wooller wants to see and examine more mammoth tusks. Have movement patterns changed over millennia as the climate has changed? Do female mammoths and their herds frequent different parts of Alaska?

He said that what happened to woolly mammoths as the world warmed at the end of the last century may also point to an understanding of the animals living in Alaska today.

Dr. “We’re seeing polar bears and caribou change their biology and behavior in response to some warming,” Wooller said. “There are parallels we can draw as well.”