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In an ancient tomb in what is now northwestern Argentina, a person was buried with a canine companion – but this animal friend was not a dog, according to new research. The burial contained a skeleton of a canid type that might have once rivaled dogs for human affection: a fox.
People and dogs have a long history. The relationship between the two species is thousands of years old. However, a new analysis of evidence from a Patagonian burial dating back some 1,500 years suggests a similar close relationship between a hunter-gatherer in southern South America and the large extinct fox species Dusicyon avus.
Archaeologists first uncovered the nearly complete D. avus skeleton buried next to a human at Canada Seca, a site in northern Patagonia, in 1991. The bones had no cut marks, so the fox had not eaten them, said the Dr. Ophélie Lebrasseur, researcher with the Wellcome Trust’s Palaeogenomics and Bioarchaeology Research Network at Oxford University School of Archeology in the United Kingdom.
In-depth analysis of ancient DNA and radiocarbon dating confirmed the species and age of the fox, and examination of collagen in the fox’s remains showed that it ate the same food as this group of people. In addition to the skeleton’s placement in the grave, the animal’s diet suggested the fox was tame and may have been kept as a pet, scientists reported Wednesday in the journal Royal Society Open Science.
This discovery adds to a growing body of evidence from burial sites on other continents indicating that individual foxes were mating and sharing bonds based on companionship.
Society of foxes and hunter-gatherers
D. avus lived from the Pleistocene Era (about 2.6 million to 11,700 years ago) into the Holocene, becoming extinct about 500 years ago. It was about the size of a modern German shepherd but much less bulky, weighing up to 33 pounds (15 kilograms).
“In general, Dusicyon avus has a type of meat food,” said Lebrasseur, who led the study with Dr. Cinthia Abbona, a researcher with Argentina’s National Council for Scientific and Technical Research. But when scientists tested the fox’s skeleton from the burial, they discovered that its diet was less carnivorous than expected, and more similar to human diets.
“That suggests that the community was feeding it, or that it was all over the community and feeding off the kitchen trash,” Lebrasseur told CNN. “It would suggest a closer relationship and integration of canids within society.”
The concept of foxes as pets in South America is consistent with evidence from other fox burials in Europe and Asia, said Dr. Aurora Grandal-d’Anglade, a paleobiologist at the Universidade da Coruña in Spain. Grandal-d’Anglade, who was not involved in the new study, described Bronze Age graves in the Iberian Peninsula that included many dogs and four foxes buried alongside humans. Researchers found that the foxes were arranged like the dogs, which suggests that they are also companions for humans.
“There is no reason why foxes could not be domesticated,” Grandal-d’Anglade told CNN in an email. “We know that people in many completely different societies keep domestic animals (not only canids, but e.g. monkeys, birds, reptiles) simply as companion animals. When looking at this, more sites appear and it seems that foxes played a role as pets.”
Finding D. avus in a human grave was surprising for another reason — although the species was once widespread throughout South America, it was previously unknown in this part of Patagonia. Hunter-gatherers who lived in the region typically stayed within a range of about 44 miles (70 kilometers), so they likely encountered the friendly fox within that range, according to the study.
“The Dusicyon avus must have been part of the immediate neighborhood, so that it could be integrated into the community,” Lebrasseur said.
What fox burials reveal about ‘man’s best friend’
The analysis also revealed what drove the foxes to extinction – or rather, what didn’t. One hypothesis suggested that foxes interbred with dogs brought to South America by European colonists, and that interbreeding eventually gave rise to the fox species. But the fox’s DNA told a different story, the study authors reported.
“Based on what we were able to recover and the technique we developed at Oxford a few years ago, we were able to suggest that the hybridization between domestic dogs and Dusicyon avus would not be able to produce fertile offspring,” said Lebrasseur.
However, it could still be that dogs were not completely innocent in the decline of foxes. With a diet similar to D. avus, dogs may have helped speed up the fox’s extinction by competing with them. Diseases that sickened foxes, Lebrasseur said, could also be contracted by dogs.
Experts often explain the domestication of dogs as something that happened because people realized they could put dogs to work as hunters or herders, Grandal-d’Anglade said. But the D. avus skeleton at Cañada Seca and other fox burials suggest that an animal didn’t have to be a useful worker to be nurtured by humans—it could be a friend.
“The proliferation of canids of different species in close contact with humans seems to indicate that it was in principle a relationship of affection, companionship,” said Grandal-d’Anglade. “The fact that we find them in many different societies and on different continents suggests that keeping animals for companionship, and not just as work or meat animals, is an ancestral trait in humans.”
Mindy Weisberger is a science writer and media producer whose work has appeared in Live Science, Scientific American and How It Works magazine.
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