An 8,100-year-old canine jawbone recovered in interior Alaska in June 2023. The bone, along with a 12,000-year-old leg bone discovered at a nearby site, are the earliest evidence that ancestors of today’s dogs formed close relationships with people in the Americas.
Credit...Zack Smith

The 12,000-Year-Old Wolves That Ate Like Dogs

Animal remains unearthed in Alaska give clues to how wolves were domesticated.

by · NY Times

As the Late Pleistocene ice age drew to a close, people and wolves began to bond. From there, it was just a few millenniums to puppy yoga and dog influencers. But the details of exactly how and when wolves were tamed and domesticated remain up for intense debate.

“There’s been millions of dollars spent to try to figure this out,” said Robert Losey, an anthropologist at the University of Alberta who studies the domestication of dogs. Despite those efforts, he said, “we still have a really poor understanding of where and how dogs originated.”

A new study has added a crucial clue in the form of a 12,000-year-old leg bone from the Swan Point archaeological site in Alaska. The DNA in those remains revealed that the animal’s mother had been a wolf, but a chemical analysis showed the creature had a fish-heavy diet likely to have been provided by people, the researchers said.

This discovery appears to capture a key moment in the budding relationship between wolves and people, offering compelling evidence of the two species drawing closer together. It’s unclear, however, whether the newly discovered animal was intentionally fed by people, or had simply learned to scavenge their trash. That has left researchers divided on just where to place the Swan Point specimen on the wolf-dog continuum.

“It may not be what we think of as domestication in the Western sense,” said Joshua Reuther, an archaeologist at the University of Alaska Fairbanks and an author of the new study, published this month in Science Advances. “But there is a very strong human-canid interaction there.”

The findings offer some of the earliest evidence of dog domestication in the Americas, older than the 10,000-year-old remains, also from Alaska, that were the subject of a 2021 study.

“There’s lots of uncertainty and unknowns about the initial dog domestication, even to the point of when it happened and where it happened,” said Ben Potter, an archaeologist at the University of Alaska Fairbanks who also worked on the new study. “But what our data points to is we’re beginning to peel back the uncertainties.”

During the tumultuous period of the Late Pleistocene — known for mass extinction, upheaval and migration — humans and wolves may have been thrown together by circumstance, finding themselves trooping in tandem across the Bering Land Bridge from what is today Siberia and into Alaska.

Wolves, then and now, mostly eat prey found on land, which in the case of ancient Alaska meant bison, mammoth and rodents. But the animal discovered at Swan Point got 57 percent of its sustenance from salmon. The researchers said this probably meant that it had a relationship, however rudimentary, with a local human population that did its own fishing.

Another site in Alaska, known as Hollembaek Hill, yielded more salmon-fed canids, the study found, including a mother, about 8,000 years old, whose fetus showed evidence of a salmon-heavy diet. Based on wolf mating patterns, the researchers concluded that the fetus was probably conceived in the depths of winter, when salmon would not have been running up the nearby Tanana River.

“The mother had access to salmon at the time of conception, or at the time of pregnancy,” said François Lanoë, an anthropologist at the University of Arizona who led the dietary portion of the study.

Experts not involved with the study agreed that the discovery was significant. There are “just very, very, very few” dog remains older than 10,000 years old, Dr. Losey said. Although the Swan Point remains showed evidence of wolf DNA, the genomic signal is not strong enough to make a conclusive species determination.

“Was it a wolf that someone was trying intentionally to feed or tame?” asked Angela Perri, an expert in human-animal interactions at Chronicle Heritage. “Or was it a wolf that was like, ‘You know, hunting caribou sucks.’”

In her view, the remains show how wolves rifling through human trash may have inadvertently begun the process of evolving from scavenger to companion, in what is known as the “trash heap hypothesis” of domestication.

But she also acknowledged the inherent uncertainty in peering into the distant past. “The study is good, but it’s just a choose-your-own-adventure situation,” Dr. Perri said.

Drs. Lanoë and Potter do not believe that the trash-heap model explains their findings.

“If wild canids just stole food scraps from time to time, it probably wouldn’t even show up” in the chemical isotopes left in the bones, Dr. Lanoë said. Dr. Potter agreed. “The most plausible explanation is that a human fed the canids,” he said.

To the Dene people, who have lived in Alaska and northwest Canada for many centuries, the debate over canine origins is in danger of missing an even bigger point.

“The idea of dogs is a very specific, modern, Western concept,” said Evelynn Combs, a tribal official from Healy Lake, an Indigenous community near Swan Point.

For Indigenous people, Ms. Combs said, dogs functioned as partners in survival, allies on a harsh landscape. The bond that developed, in her view, cannot be confined to genes or isotopes. “It touches on the spiritual,” she said.

Discover More in Health and Science