Dogs Have Been Our “Best Friends” for 23,000 Years, Study Says
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A common saying is that dogs are a man’s best friend. For many people, their dog is a member of their family. Dogs have also supported humans in many working and support roles, such as therapy dogs, dogs working on farms, and dogs supporting the military and emergency services. It is not only in modern times that dogs and humans have developed strong relationships, as dogs and humans have lived and worked alongside each other historically. Now, scientists and historians have uncovered evidence that suggests that there are links between humans and dogs going back more than 23,000 years. says Ars Technica.
The Aim of the Research
Dr. Angela Perri is an archaeologist at Durham University. Perri and her team of colleagues’ aim was to use genetics to narrow down where and when dogs evolved. They did this by comparing genome sequences. Genomes can collect random and small mutations at a predictable rate, so comparing the sequences allows geneticists to determine when two animals shared a common ancestor. Prior to this research, Perri and her team had previously used sequenced genomes from both ancient dog breeds and modern dogs to determine when dog breeds had either interbred or split. Using the same theory and process, the team repeated the research using human genomes.
The Findings of Perri’s Research
The results of the team’s study show that it was more than 23,000 years ago that dogs first became domesticated, and it was the people of northern Siberia that first domesticated canines. Perri noticed that humans and dogs split and merged at roughly the same time, and this is backed up by recent research findings by other scientists. The findings allowed the team to create a genetic map of the shared journey of canines and humans.
The Split in Dog and Human Populations
When the team created their genetic map, they discovered that there was a split in the populations of both humans and dogs, and this occurred approximately 16,000 years ago. Evidence uncovered by archaeologists suggests that humans were traveling south along North America’s Pacific coast at this time, as they were bypassing the huge sheets of ice that covered most of North America. The Arctic dog population split at a time that coincided with the humans’ journey. One of the Arctic dog breeds that are still around today was the Siberian Husky. The new branch that made the split is called the haplogroup A2b. They are the maternal linage of all indigenous North American dogs. The DNA of modern and ancient dogs shows that Siberian Huskies and canines in the haplogroup A2b shared a common ancestor for the last time, approximately 16,400 years ago.
The timing is consistent with the first people moving to the Americas, suggesting that humans and dogs traveled together. Kelsey Witt Dillon is a molecular biologist at Brown University, and she also co-authored the paper with Perri. According to Witt Dillon, most modern dog breeds look like European dogs, with very few breeds remaining that have a lineage with the haplogroup A2b. Some examples of breeds that have a small amount of the haplogroup A2b lineage include Chihuahuas and the Carolina Dog. Witt Dillon says that researchers believe that North American dogs were killed in the same way as the Native Americans, which was through the warfare of the Europeans, and from diseases caught from European dogs. Eventually, the European dog breeds introduced to America by the European colonizers replaced the ancient North American dogs, thus also replacing the genetic lineages.
Links Even Further Back in Time
While scientists already knew that dogs and humans were connected in their movements at this time, there is now evidence that the connection between the movements of the two species goes back even further. It is believed that there were occasional relations between the Ancient Northern Siberians and the indigenous North Americans. Although the two groups branched off from each other around 24,000 years ago, the two groups continued to mingle. Dog genome studies show that the haplogroup A2b separated from the rest of the dog family tree just under 23,000 years ago, which coincided with the human population split. It was also at the time of the onset of the Ice Age.Perri and her colleagues believe that this suggests that dogs were domesticated by North Siberians more than 24,000 years ago. When the new population of Ancestral North American was formed after branching off, they also took along their dogs.
The Next Steps
According to Witt Dillon, the team intends to extend its research further. Next, they want to narrow down the timing of dog domestication. They also want clarification of when dogs first came to the Americas. In a bid to answer these questions, the team will sequence additional dog genomes, focusing predominantly on dogs from near Beringia or in Siberia. They hope that the information this reveals will fill in the gaps on their current timeline. It also possible that the current research could lead to a greater understanding of how domesticated dogs reached Central Europe at approximately the same time as they reached the Americas. Human interactions are potentially the reason behind this, as Western Eurasia’s people interacted with the Ancient Northern Siberians in much the same way as the Ancestral Native Americans.
David Meltzer, an archaeologist at Southern Methodist University, is another co-author of the paper. He suggests that the explanation is as simple as the dogs followed the humans they met. Even if the dogs only had brief interactions with the humans, they may simply have followed them, leading to the dispersion of domesticated dogs from Northern Siberia to other parts of the world. However, this theory is based purely on his observations as a dog lover rather than on any scientific evidence.
