A recent study provides insights into how long humans in the Americas have shared bonds with the ancestors of modern dogs, while also exploring a thought-provoking question: What defines a dog?
The saying “Dog is man’s best friend” may be a well-known phrase, but the timing of when this friendship began has puzzled scientists for ages.
A new study led by a researcher from the University of Arizona is making progress in uncovering how Indigenous peoples in the Americas formed connections with early dogs and wolves.
Published today in the journal Science Advances, the research is based on archaeological findings from Alaska. It indicates that humans began cultivating close relationships with the ancestors of today’s dogs approximately 12,000 years ago—around 2,000 years earlier than previously known records from the Americas.
“We now have evidence demonstrating that canids and humans established close ties earlier than previously understood in the Americas,” stated François Lanoë, the lead author of the study and an assistant research professor at the U of A School of Anthropology within the College of Social and Behavioral Sciences.
“For individuals like me who are intrigued by the migration to the Americas, it’s vital to investigate whether the first Americans brought dogs with them,” Lanoë noted. “While we can speculate until archaeological evidence is found, proving it is challenging. Thus, this research offers significant insights.”
In 2018, Lanoë and his team discovered a tibia, or lower leg bone, of an adult canine at an archaeological site called Swan Point, located about 70 miles southeast of Fairbanks. Radiocarbon dating revealed that this canine lived around 12,000 years ago, at the end of the Ice Age.
Additionally, the team excavated another specimen in June 2023—a jawbone from an 8,100-year-old canine at a nearby site named Hollembaek Hill, which also indicates signs of potential domestication.
The decisive evidence? A fish-based diet
Chemical analysis of both bones revealed a significant presence of salmon proteins, implying that the canine had frequently consumed fish. This was unusual for canines in this region during that era, as their primary diet consisted of land animals. The most plausible explanation for the inclusion of salmon in their diet? A reliance on humans.
“This serves as the definitive evidence since they weren’t actively hunting for salmon in nature,” commented Ben Potter, an archaeologist with the University of Alaska Fairbanks.
The researchers believe that the finding from Swan Point helps to establish some of the earliest known close bonds between humans and canids in the Americas. However, it’s too soon to determine if this discovery represents the earliest domesticated dog in the region.
This is why the study is particularly important, according to Potter: “It asks the fundamental question, what exactly is a dog?”
Lanoë mentioned that the remains from Swan Point and Hollembaek Hill might be too ancient to be genetically connected to known, more recent dog populations.
“In terms of behavior, they appear to behave like dogs, as they consumed salmon that was provided by humans,” Lanoë said. “However, genetically, they don’t align with any known breeds.”
He added that these might have been tamed wolves rather than fully domesticated dogs.
‘Our companions have always been with us’
This research continues a long-standing collaboration with tribal communities in Alaska’s Tanana Valley, where archaeologists have been conducting work since the 1930s, noted Josh Reuther, co-author and archaeologist associated with the University of Alaska Museum of the North.
The research team regularly discusses their research plans with the Healy Lake Village Council, which represents the Mendas Cha’ag people native to the area, prior to conducting studies, including this one. The council also provided consent for the genetic analysis of the new specimens.
Evelynn Combs, a Healy Lake community member who grew up exploring archaeological sites in the Tanana Valley, has had a long-standing relationship with Lanoë, Potter, and Reuther since her teenage years. Now an archaeologist, Combs works in the tribe’s cultural preservation office.
“It may seem small, but it’s profound to honor the land’s inhabitants by obtaining proper consent,” Combs remarked.
According to Combs, the residents of Healy Lake have always regarded their dogs as mystical companions. She noted that nearly every villager shares a close bond with at least one dog. As a child, she explored her village alongside a Labrador retriever mix named Rosebud.
“I find it beautiful that, in the historical record—no matter how far back—we share this cultural experience of love and companionship with our dogs,” she expressed. “It assures me that these relationships have persisted through time, and we can see evidence of that bond from thousands of years ago.”
