Researchers have discovered the remains of what may be the world’s earliest domesticated wolves in a cave in southwest Germany. Describing the fossils in the journal Scientific Reports, they explain that the specimens could not be classified as either ancient wolves or modern dogs, but encapsulated “almost the entire breadth of genetic diversity of all contemporary and ancient dogs and most wolves.”
It is generally accepted that the domestication of wolves first occurred around 16,000 years ago in Eurasia, although whether this process began in a single location or took place at several sites simultaneously is not known. Regardless of what may have been going on elsewhere, though, it seems that the residents of the Gnirshöhle cave in what is now Germany had already begun to tame wolves at this time, and may therefore have been the world’s first dog breeders.
This small but hugely significant cave is located in the Hegau Jura region, which was inhabited by the Magdalenian cultures towards the end of the Pleistocene.
After analyzing the morphology, genetics, and isotopes of the Gnirshöhle canid remains, the researchers noted that the specimens seem to be descended from multiple ancient wolf lineages, including one that doesn’t match any other canid lineage from the region. This implies that the cave’s residents may have tamed and reared wolves from numerous subpopulations, some of which originated outside of Europe.
Results of the isotope analysis indicated that the canids consumed a low-protein diet that differed greatly from that of wild wolves, thereby suggesting that they had been fed by humans. "Thus, we consider the Gnirshöhle canids to likely represent an early phase in wolf domestication — facilitated by humans actively providing a food resource for those early domesticates," explain the researchers.
Commenting on these findings, study author Chris Baumann explained that “the closeness of these animals to humans and the indications of a rather restricted diet suggest that between 16,000 and 14,000 years ago, wolves had already been domesticated and were kept as dogs.” It’s worth noting, however, that Gnirshöhle may not have been the only site of wolf-domestication at this time, and the researchers are keen to point out that similar processes may have been occurring elsewhere.
A closer examination of the specimens’ mitochondrial genomes allowed the team to identify specific wolf and dog genes, which they were then able to trace back to a common ancestor that lived roughly 135,000 years ago. While this doesn’t necessarily mark the point at which domestication began, the researchers say it provides an “upper time limit of such events.”
Summing up their findings, the study authors explain that “while we cannot address the question of the domestication event's singularity, our results support the hypothesis that the Hegau Jura was a potential center of early European wolf domestication.”