Did you know that when you share food with your dog, you are participating in a practice that’s likely part of the reason dogs are in our lives in the first place? A new study published by University of Arizona researchers in the journal Science Advances found that humans in North America likely shared their food with local canines as far back as 12,000 years ago, which suggests the two species began their close relationship about 2,000 years earlier than previously thought. The authors of the study say their findings may point to the earliest recorded canine domestication in the Americas.
At archeologist sites in the Alaska interior, researchers found two significant bones that provide new insights about early dog-human relationships. The first, discovered in 2018, was a shin bone radiocarbon dated to 12,000 years ago, or the end of the Pleistocene era—our last Ice Age. The second was a jaw bone, excavated in June 2023 at a site not far from the first. It was 8,100 years old. The analysis showed that these bones belonged to canids, a group that includes dogs, but also coyotes, foxes, jackals, and wolves.
And here’s what’s exciting about these old bones: Chemical analysis revealed the presence of salmon proteins, which suggests that people were feeding these proto-dogs. Lead researcher François Lanoë explains in his recently published paper how his team did not find the same marine proteins in modern and ancient wolf bones from other sites in the Alaska interior—sites that were not known human campsites. These latter canids were partial to hunting land animals. Lanoë and his co-authors argue that the canids who shared space with humans also accessed salmon through them.
Photo by Zach Smith.
“This is the smoking gun because they [canines] are not really going after salmon in the wild,” Ben Potter, study co-author and UAF archaeologist, said in a press release.
As for what species the canines actually were, the authors said that the analysis of their bones indicates they didn’t resemble the domesticated dogs we know today, but could have been tamed wolves. “Behaviorally, they seem to be like dogs, as they ate salmon provided by people,” Lanoë adds in the release. “But genetically, they’re not related to anything we know.”
How dog domestication actually happened is still a mystery, or at least a point of contention among experts. There are, for example, theories that humans domesticated canines as useful companions; others posit that canines domesticated themselves for similar reasons. Researchers don’t know if domestication happened once or multiple times across the world. In the Americas, it’s still unclear whether canines arrived with humans, or if domestication began after humans arrived. The new University of Arizona study points to just one example of the domestication process at work, with shared food being a component. It’s not a definitive answer to the when and how of dog domestication, but another fascinating chapter in the long, continuing story of the dog-human relationship.
