their domestication occurred earlier than previously thought

Following decades of research, it is now generally accepted that the pet dog (Canis familiaris) descended from wolf ancestors (Canis lupus). However, the exact chronology of the transition from wolf to dog is not yet known with certainty and is still the subject of much debate among scientists. Today, DNA sequencing technologies offer a new dimension to archaeopaleontology, by providing greater precision in this wolf-dog transition. A new study published in Direct Science In this sense, it was possible to date the dog bone from Eralla (Spain) between 17,410 and 17,096 years and identify it as belonging to a dog. Thus, this bone is the oldest discovered to date in Europe, and suggests that the wolf evolved into a dog much earlier than previously thought. Their domestication therefore also took place earlier.

Although the geographical and chronological origin of the evolution from wolf to dog is still subject to debate, scientists agree on at least one point: the dog was the first animal domesticated by humans. From this early nurturing was born a thousand-year-old relationship of complicity between man and animal, which continues to this day.

Although some studies suggest that the two species (wolves and dogs) began to genetically diverge at least 100,000 years ago, it is more commonly accepted that this diversification and domestication began between between 40,000 and 15,000 years ago, bones of wolves with dog characteristics were found. and dated to this period. It is also possible that this process of genetic evolution arose through the self-domestication of dogs, as they adapted and became attached to human conditions.

However, the state of preservation of the bones found greatly hinders the accuracy of dating, so several studies on dog evolution contradict each other. A study published in 2016 actually assumed that the domestication of the dog would occur in two different stages, while another, a year later, suggested the opposite.

With the advent of DNA sequencing, the opinions of geneticists also contributed to some chronological confusion. However, strong genetic evidence has revealed that the ancestors of all modern dogs may have genetically split about 40,000 years ago into two distinct populations: one that gave rise to East Asian breeds and the other on the origin of the races of Europe, Africa, South and Central Asia.

On the other hand, if the oldest dog bones discovered are thought to be from the Upper Palaeolithic of Western Europe (between 17,000 and 12,000 years ago), the new study, from the University of the Basque Country, indicates that the canine humerus was discovered. in the caves of Eralla (Zestoa, Gipuzkoa) is over 17,000 years old. Excavated in 1985, the nearly complete humerus could not be identified. Thanks to genetics, the researchers of the new study revealed that it was indeed a dog, and therefore the oldest dog bone discovered (in Europe) by modern research.

The humerus of the Eralla dog, excavated in 1985. © University of the Basque Country

A line of Magdalenian dogs

The conflicting data collected on the evolution of the dog will be partly the result of the limitations of morphological identification. But because DNA degrades easily and is rarely preserved, archaeologists are often forced to stick with the shapes of bones. However, there may be errors, as wolves may have had greater morphological diversity in the past, possibly depending on the region.

Years of experience in morphological identification, supported by DNA sequencing and radiocarbon dating, led to a significant discovery, giving an age of 17,410-17,096 years to Eralla’s dog. This means that this dog lived during the Magdalenian period of the Upper Paleolithic (a civilization that flourished 17,000-12,000 years ago), making it one of the oldest known domesticated dogs to have existed to this day on the European continent.

Furthermore, it would share a mitochondrial lineage with other Magdalenian dogs discovered in the Gironde and Bonn-Oberkassel, with ages of 15,114 to 14,237 and 14,809 to 13,319 respectively. The origin of this line of dogs closely coincides with the ice age, which raged in Europe about 22,000 years ago.

” These results raise the possibility that wolf domestication occurred earlier than expected, at least in Western Europe. said Concepción de-la-Rúa, head of the Human Evolutionary Biology group at the University of the Basque Country and co-lead author of the new study. According to the expert, the time is related to a possible interaction of Paleolithic hunter-gatherers with wild animal species, such as the wolf. This assembly may actually have been stimulated at the level of glacial refuge zones (such as Franco-Cantabrian), to survive in harsh conditions.

Source: Science Direct