Ottawa researchers part of team investigating big questions

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The 1960s cartoon The Flintstones made a lot of mistakes when it came to interactions between prehistoric humans and ancient animals. In the first place, humans did not coexist with dinosaurs, much less ride them.

But humans have encountered woolly mammoths, and resourceful hunter-gatherers who just arrived in North America during the late Ice Age may have been responsible for their extinction.

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The exact nature of that relationship is being investigated by an international team of researchers, including Clément Bataille of the University of Ottawa.

Using high-resolution isotope profiling, Bataille and colleagues used high-resolution isotopic profiling to find a length 1 specimen belonging to a female mammoth named Elmayujaye (also known as Elma), excavated from the 14,000-year-old Swan Point site in Alaska’s Tanana River basin. The tusks of the meter were analyzed. The results were reported in a paper published in Science Advances in early January.

Tissues provide a record of an organism’s experience with environmental factors such as climate and food availability.

“For example, I was born in the Caribbean and have lived in France, Canada, and the United States. My tissues have chemical signals for all of these,” says an interviewer from France, who studies prehistoric horses. Bataille said Friday.

“What’s interesting about the tusk is that it’s similar to tree rings. You can track where that mammoth was traveling.”

There are many questions about mammoth behavior, how they lived, and why their numbers declined and disappeared after the mammoth species roamed the frozen tundra for about 300,000 years.

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Mammoths, like caribou, are thought to have roamed, moving from one place to another and never coming back. Elam’s tusks are a record of her wanderings, and the study is proof of concept that scientists can track mammoth movements, Bataille said.

At the end of the last ice age, humans and mammoths coexisted in Alaska for about a thousand years. Many things were changing during this time, including the climate becoming warmer and more humid.

Mammoths became extinct on the mainland about 10,000 years ago. Small, isolated populations on St. Paul Island in the Bering Sea and Lange Island in the Arctic Ocean survived until about 4,000 years ago, when they became extinct, probably because mammoths could no longer roam and became inbred.

Bataille said there are many interesting questions about the Alaskan mammoth, including whether its presence attracted humans to North America.

It appears that early Alaskans built their settlements based in part on the presence of mammoths, using them as raw materials and perhaps food. Adult mammoths weighed more than 5 tons and would have been an attractive food source. They would have been even more attractive to hunters if their movement across the terrain was regular and predictable.

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Researchers believe Elma traveled about 10,000 kilometers during her lifetime. That sounds like a lot of wandering, but humans walk about 50,000 miles in a lifetime, Bataille said.

In an earlier study of a pair of tusks from a male mammoth named Kick, which lived in the cold pre-human era some 17,000 years ago, scientists discovered a different story.

Mr. Kick died at the age of about 30, probably from illness or starvation. Mammoths can live 50 to 60 years.

In contrast, Elma was about 20 years old and in perfect health when she died. “Something happened to her. She may have been chased,” Bataille said.

Mammoths are herbivores and prefer open grasslands. Elma’s fangs showed that she was familiar with forests and swamps. During her 3,000 years between Kick’s life and Elma’s, Alaska’s climate changed and as a result, the invasion of woody shrubs fragmented the mammoth’s grassland habitat.

“There were many obstacles to her movement,” Bataille said. Meanwhile, Kick had the opportunity to spread his genes far and wide.

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Questions remain about woolly mammoths, including whether they behaved like modern-day wild elephants, where infants and young move with matrilineal herds until they reach adulthood.

The Swan Point ruins also contain the remains of a young mammoth and a baby, indicating that a herd existed in the area. Analysis showed that they were closely related to Elma, but she was not their mother.

This is the first clear evidence that mammoths lived in herds. Bataille uses calcium isotopes to tell if Elma has breastfed. This is thought to indicate that Elma gave birth to her own child.

It is estimated that half of the species in the megafauna (large animals) went extinct at the end of the last ice age. The saber-toothed tiger has disappeared. The camels and bison survived. Horses became extinct in the Americas, but survived in Eurasia.

Bataille said this research has implications for the conservation of living megafauna. “We are also experiencing climate change.”

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