Mammoths topped the menu for Ice Age people in North America.

The first humans to spread across North America during the last Ice Age put mammoths at the top of their menu, according to scientists who have obtained the first direct evidence of the diet of these ancient people.

Researchers deciphered the diet of a woman who lived about 12,800 years ago based on chemical clues in her son’s bones, whose remains were found in southern Montana. Because the 18-month-old was breastfeeding at the time of her death, her bones contained chemical fingerprints of her mother’s diet, which passed through her milk.

They discovered that its diet is mostly the meat of megafauna – the largest animals in an ecosystem – with an emphasis on mammoths. Megafauna made up about 96% of their diet, with mammoths making up about 40%, followed by elk, bison, camels and horses, and small mammals and plants accounting for negligible amounts.

“Megafauna, especially the enormous mammoths of Columbia, provide enormous packages of meat and energy-rich fat. One animal sustains a dependent community of children, caring women, and less mobile elders for days or weeks. can keep while hunters search for them. The next kill,” said archaeologist James Chatters, co-lead author of Applied Paleoscience, a Washington-based archaeological consultancy. The study was published Wednesday in the journal Advances in science.

Columbian mammoths, cousins ​​of today’s elephants, were about 13 feet (4 m) tall at the shoulder and weighed up to 11 tons.

The mother and child were part of the Clovis culture dating back to around 13,000 years ago. These highly mobile and nomadic people are associated with artifacts that include stone spear points suitable for killing large prey, large stone knives, and scraping tools for stripping meat.

The findings support the idea that the Clovis people, whose predecessors crossed a land bridge from Siberia to Alaska, foraged for plants and hunted small animals rather than preying on the landscape. Focused on hunting.

This strategy seems to have enabled these people to spread rapidly across North America and then South America – in just a few centuries – as they followed hunting migrations over vast distances.

“These findings also help us understand the megafaunal extinction at the end of the last ice age,” said Ben Potter, an archaeologist at the University of Alaska Fairbanks and co-lead author of the study. may have played a more important role than sometimes thought.”

Clovis people inhabited North America during the twilight of the Ice Age, when a warmer climate reduced habitat for mammoths and other large herbivores. These animals were familiar with predators such as saber-toothed and scimitar-toothed cats, but had never encountered human predators before.

“The Clovis people were highly sophisticated hunters, specializing in hunting megafauna over a period of more than 10,000 years on the plains stretching from Eastern Europe to the Yukon.

Arriving south of the glacial ice in North America, they met simple prey under environmental stress. By emphasizing megafauna in their diet, these newcomers added to that stress, increasing the likelihood of extinction,” Chatters said.

The skull and other bone fragments of the child, informally known as the Anzac Boy, were discovered in 1968 in an ancient collapsed rock shelter on a field near Wilsall, Montana.

To determine the protein portion of his mother’s diet, a method called stable isotope analysis was used, in which elements trace different forms—isotopes—of carbon and nitrogen, which differ only by the number of neutrons in their nuclei. I was different.

“We’re all made of elements, like carbon and nitrogen, and so is our food,” said isotope paleoecologist and study co-author Matt Voller, director of the Alaska Stable Isotope Facility at the University of Alaska Fairbanks.

The mixture of isotopes of these elements can provide the chemical signature of a particular food – beef or peas, for example – that is incorporated into the consumer’s body tissues. The researchers estimated the boy’s diet to be two-thirds from nursing and one-third from solid food.

They compared the mother’s diet, as the analysis showed, to that of various herbivores and carnivores of the same period, including big cats, bears and wolves. Its diet resembled that of Homotherium, a now-extinct scimitar-toothed cat that preyed on mammoths.

The results of the study are consistent with previous archaeological findings.

“We’ve long known from indirect evidence that Clovis artifacts are often associated with megafauna bones and that those artifacts emphasize the killing and processing of large prey,” Chatters said.