Genetic Study Finds Earliest Known Dog, Dating Back 15,800 Years

A fragment of skull pulled from the Pınarbaşı rock shelter in what is now Türkiye has rewritten the genetic record for dogs. Sequencing confirmed the sample, dated to 15,800 years ago and determined to be from a female puppy on the basis of teeth, was clearly that of a domestic dog. The find, reported in two papers published Wednesday in the journal Nature, pushes the oldest direct genetic evidence for dogs back by roughly 5,000 years.

The earliest unequivocal genetic evidence had previously been associated with dog remains from Mesolithic archaeological contexts approximately 10,900 years ago. According to study co-author Laurent Frantz of Ludwig Maximilian University of Munich, the Pınarbaşı puppy was perhaps a few months old and "probably looked like a small wolf" when it lived. The bone itself was so degraded it reportedly resembled freeze-dried coffee, yet yielded a full genome.

Researchers also generated whole genomes from canid remains at Gough's Cave in the UK, dated to 14,300 years ago, and from dogs excavated from two Mesolithic sites in Serbia: Padina, between 11,500 and 7,900 years ago, and Vlasac, 8,900 years ago. The analyses indicate that a genetically homogeneous dog population was already widely distributed across Europe and Anatolia during the Late Upper Palaeolithic, by at least 14,300 years ago.

The Gough's Cave specimen, a jawbone now held by the Natural History Museum in London, carries its own unsettling context. Although the humans associated with these two early dogs were both groups of Ice Age hunter-gatherers, they were strikingly different, says co-author William Marsh, a palaeogeneticist at the Natural History Museum. "At Gough's Cave, we have butchering and processing of humans after death that included cannibalism, as a funerary behavior akin to burial. Similar post-mortem modification, albeit not definitively for consumption, was found on the dog remains," Marsh said.

One paper was led by Anders Bergström, Pontus Skoglund and colleagues, who analyzed the genomes of some 200 ancient dog and wolf remains, while the other, led by William Marsh, Lachie Scarsbrook and Laurent Frantz, reported the genome sequences of the two dogs dating back 14,000 to 16,000 years ago. The research team for the Türkiye and Europe study involved experts from 17 institutions internationally, led by the Natural History Museum, the University of Oxford and LMU Munich. The companion study was led by the Francis Crick Institute, the University of East Anglia and the Max Planck Institute for Evolutionary Anthropology.

The second team identified another very early dog after screening hundreds of suspected dog and wolf remains, using a technique in which ancient DNA is captured among microbial contaminants, allowing researchers to discern dog from wolf in more than 130 samples. They identified 14 dogs that lived among hunter-gatherers in Europe, including a 14,200-year-old sample from a Swiss site called Kesslerloch.

The genetics point to a lineage that looks nothing like today's Arctic breeds. The Pınarbaşı and Gough's Cave dogs were found to be more closely related to the ancestors of present-day European and Middle Eastern breeds such as boxers and salukis than to Siberian huskies. The dog, descended from an ancient wolf population separate from modern wolves, was the first animal domesticated by people, with animals such as goats, sheep, cattle and cats coming later.

One of the study's more surprising findings concerns what happened, or more precisely what did not happen, when farming arrived in Europe roughly 10,000 years ago. That Neolithic wave brought sweeping genetic change to human populations across the continent, but dogs largely escaped the replacement. "Dogs were clearly important to our ancestors, as the first farmers seem to have adopted previous hunter-gatherer dogs into their groups as they moved into Europe," said Skoglund. "Dogs have been by our side as humans underwent major lifestyle transitions and complex societies emerged," said geneticist Anders Bergström of the University of East Anglia, lead author of the other study.

Marsh said the DNA evidence suggests dogs were present in various locales in western Eurasia by 18,000 years ago and were already quite different genetically from wolves. "We putatively predict that dog and wolf populations diverged a lot earlier, likely before the last glacial maximum of the Ice Age, so before 24,000 years ago. Although saying that, there is still a great degree of uncertainty," Marsh said.

Skoglund, who called the origins question "just an interesting mystery," noted that dogs are most likely a mix of two types of grey wolves, yet a "genetic abyss between dogs and wolves" persists. "The search for the missing link continues.