NYT: Hungry, hungry humans ate all the woolly mammoths

Are scientists finally going to stop pretending that climate change wiped out American mega-fauna just as the ancestors of Amerindians coincidentally arrived?

We may finally be making some progress toward the resolution of one of the dumbest scientific controversies of all time: Why did the woolly mammoths and most other mega-fauna of the Americas go extinct almost exactly at the moment the Amerindians showed up?

The answer, obviously, was that the Indians ate them.

Why? Because they were delicious.

Jared Diamond wrote a memorable article around 1990 about just how wonderful it must have been for the Indians to arrive in two entire continents full of giant animals too dumb to know how lethal hardened Siberian-Beringian hunters were.

The word “Beringia,” the hyperborean region below the current sea level that was exposed when the oceans retreated during the last Ice Age, just makes me shiver thinking about it. It seems very odd that this far north would not be covered in glaciers when Central Park in Manhattan and Indianapolis were buried in ice:

Yet, Beringia appears to have been a weird far northern refuge for Siberian pioneers during the last Ice Age.

We still aren’t sure how the ancestors of the New World Indians broke out of the strangely non-ice covered Beringia. By boat down the Alaskan panhandle? Through an inland corridor through the ice sheets?

But it’s easy to imagine their joy when they finally reached the grasslands of the American heartland covered in mammoths, camels, horses, and other large, tasty critters, few of whom (other than maybe the bison) seemed to recognize the newcomers as death-on-two-legs.

Yet, for the longest time, that has been considered some fringe racist libel on the ancestors of American Indians, who no doubt were vegetarian ecologists, or something.

Personally, the idea that Amerindians blitzkrieged (to use Jared Diamond’s term) across the New World sounds admirable to me, but it was highly unpopular among academics since the 1960s.

From the New York Times science section:

Mammoth: It’s What Was for Dinner

A study of a 12,800-year-old skull of a toddler offers a glimpse at how early Americans found food, and how their hunts may have led to a mass extinction.

By Carl Zimmer

Dec. 4, 2024

For millions of years, North America was home to a zoo of giants: mammoths and mastodons, camels and dire wolves, sloths the size of elephants and beavers as big as bears. And then, at the end of the Pleistocene Epoch about 12,000 years ago, most of them vanished.

Scientists have argued for decades about the cause of their extinction. Now, a study analyzing the ancient bones of a young child who lived in Montana suggests that early Americans hunted mammoths and other giant mammals to oblivion.

“I was surprised to see things fit so nicely,” said Ben Potter, an archaeologist at the University of Alaska Fairbanks and an author of the new study, which was published on Wednesday in the journal Science Advances.

For decades, most paleontologists blamed the climate for the disappearance of North America’s megafauna. Their extinction coincided with the end of the last ice age, a time when the planet quickly warmed and glaciers retreated northward. The large mammals appeared unable to adapt.

Couldn’t they have walked north?

Wouldn’t Chicago be a better place to graze when it stopped being covered by a half-mile thick glacier?

How hard is it to adjust to the weather getting nicer? Don’t living things in North America do it every spring?

But in the 1960s, the American geoscientist Paul Martin challenged that hypothesis. The last ice age was part of a cycle of warming and cooling that had lasted for millions of years. Why had the megafauna survived earlier periods of warming, but not this one?

Martin believed that the difference was people. At the time, researchers were discovering some crucial clues about how humans had spread from Asia across the Bering Land Bridge into North America. They discovered that the oldest known archaeological remains in North America — stone spearheads known as Clovis points — dated to the end of the ice age, suggesting that their arrival coincided with the extinctions.

Martin argued that people had made their way into North America as the glaciers receded, and they began hunting the continent’s big game. The large mammals had never encountered our species before, leaving them with few defenses.

His “overkill hypothesis” gained traction over the years. Some researchers have even argued that the same wave of people who hunted down giant mammals in North America caused a similar wave of extinction when it got to South America.

Same as newcomer people quickly wiped out dodo birds in Mauritius, moa birds in New Zealand, and roc birds in Madagascar. We are hungry, hungry humans.

But some scientists were skeptical. Critics argued that there was little clear-cut evidence from archaeological sites of humans killing and eating giant mammals. Instead, they said that early Americans ate small mammals, fish and plants. Some claimed that Clovis points weren’t even strong enough to pierce a mammoth’s hide.

Dr. Potter and his colleagues recently tackled the debate from a new direction: by investigating the diet of the Clovis people from the chemical composition of their bones.

A famous skeleton of a toddler who died about 12,900 years ago was dug up in 1968 on the Anzick ranch in Montana. He was buried along with Clovis culture tools and weapons. The Clovis culture is the oldest known paleo-Indian technology in the Lower 48 states.

It’s enormously hard to get legal permission to scientifically study ancient remains found on government land in the United States (hence, much of what we know about the peopling of North America comes recently from Canada and Mexico), but the laws don’t apply to private property.

One of the scionesses of the ranch, Sarah Anzick, became a genetic researcher. She eventually went ahead and analyzed the ancient DNA, discovering that the Anzick Child was related both to Siberians and to Central and South American Amerindians more than to North American Indians, suggesting that his kin had later pushed on south. (Montana is a warmer place to live than Siberia or now-inundated Beringia, but Colombia was really nice before Old World tropical diseases arrived after 1492.)

Eventually, researchers found a member of the Crow tribe named Dr. Shane Doyle, who felt that the real history of New World Indians was awesome, and he helped get enough permissions to go ahead with a second study of isotopes in the Anzick Child.

… They concluded that over 40 percent of the Anzick diet came from mammoths. The second most common meal was elk or bison. Small mammals made up only 4 percent of their diet, at most. …

Shane Doyle, a member of the Crow Tribe who coordinated the consultation with local Indigenous groups, said that the results offered a striking glimpse at what life was like for early Americans. “These folks faced down some of the steepest odds of all time, and they not only survived, but they thrived,” Dr. Doyle said.

Indeed.