How did dogs come to be our closest animal companions? In the July Scientific American writer Virginia Morell reports on the latest insights into this longstanding mystery from genetics, archaeology and paleontology. It’s a fascinating story, not least because the relationship between humans and dogs has changed over time and from culture to culture: Dogs have functioned variously as hunting partner, guardian, ritual sacrifice and meal. Here Morell describes the relationship between the Kitoi hunter–gatherers of Siberia and their dogs:

“Dogs were tablemates with people; they were eating the same things,” says Robert Losey, an archaeologist at the University of Alberta in Edmonton. The two species even shared a tapeworm parasite, which is normally found only in carnivores—a sign of just how close together the people and dogs were living.

A highly mobile culture, the Kitoi traveled across the forested lands of today’s southern Siberia, hunting red deer, boar and bear, and fishing in Lake Baikal. They also pursued the freshwater seals in the lake, most likely in the spring when the ice began to thin, and dogs could sniff out the seals’ pupping dens. Dogs with this talent were likely rare, Losey says, explaining that the local people today claim that only one in 25 dogs has the skill. “So an adept dog would have been very valuable for a hunter.”

Certainly, the Kitoi prized their dogs, which were about the size of Siberian huskies and looked much like that breed—although the resemblance is only superficial. (In a 2012 genetic analysis of dog breeds and wolves, Greger Larson of the University of Oxford in England and his colleagues showed that there is little or no evidence to support claims linking modern breeds with those of antiquity. Most modern breeds endured significant population fluctuations during the last 100 years, and several breeds including Bernese mountain dogs and Italian greyhounds went extinct during the World Wars, and were only later re-created by crossing other breeds to produce a dog that looked like the originals—but they lacked any genetic relationship to them.) Not only did the Kitoi and their dogs share the same diet and parasites, they also shared the same cemetery on the shores of Lake Baikal. “It’s a stunning landscape,” Losey says, “and the Kitoi had an elaborate mortuary tradition, which they extended to their dogs. They treated them just like a person.”

Indeed, in some places the gravediggers moved aside human remains to make room for a prized dog. “One was buried with a necklace of four red deer-teeth pendants, the same type of necklace the Kitoi wore. Another had a spoon tucked beside it and others were found with stone tools.” The dogs themselves were carefully positioned. Some were placed in a crouching pose with their heads resting on their paws and others were laid curled on their sides, as if asleep. Two dogs were buried with an adult male human; one curled next to him on his right, the other to his left. “People only do this when they have close emotional bonds with their animals,” Losey observes, “and the Kitoi clearly did with their dogs. A dog was a member of the family, and treated as such when it died.”

For more on dog evolution check out Morell’s July feature story.