Researchers have long been fascinated with the unique, reciprocal relation between humans and dogs; one that is based on mutual recognition and affection. According to some scientists, the bond between the two species is the due to thousands of years of evolution, resulting in specific changes to our own body chemistry.
As part of a research last year, a team of Japanese scientists discovered that both humans and dogs produce a certain hormone known as oxytocin, every time they gaze at each other. This, as the researchers points out, is the same hormone that is released inside a human mother when she looks at her baby. Higher amounts of oxytocin were found to be released during talking or petting. Robert Losey, an anthropologist at the University of Alberta, said:
It’s a very compelling study, that even on a chemical basis we get this kind of biological impulse to bond, and animals have the same impulse to bond with us.
Losey, who is invested in tracing the historical relationship between humans and dogs, is currently working at an excavation site in Siberia. Home to Lake Baikal, the deepest freshwater lake in the entire world, the area has been found to contain skeletal remains of dogs dating back 5,000 to 8,000 years in the past. Analysis of the site has revealed that the two species were buried side-by-side in cemeteries. The discovery, according to the researchers, points to the some of the oldest evidence of dog domestication, while also indicating that the animals were held in high regard just as humans. Losey added:
The dogs were being treated just like people when they died. They were being carefully placed in a grave, some of them wearing decorative collars, or next to other items like spoons, with the idea being potentially that they had souls and an afterlife.
For instance, one of the Lake Baikal graves was found to house the skeletal remains of a man, flanked by his two dogs, one on each side. What is more, chemical examination of the retrieved dog bones suggests that the animals survived on the same diet as humans. Speaking about the find, the team explained:
Globally you can see that there are more dog burials in prehistory than any other animals, including cats or horses. Dogs seem to have a very special place in human communities in the past. As soon as we see skeletal remains that look like the modern dog—say 14,000 years ago—we see dogs being buried.
Scientists believe that the Eurasian grey wolf is the common ancestor of all modern dogs. Archaeological studies have shown that one of its subspecies split away and started interacting with humans as early as 30,000 to 40,000 years ago. This happened when the animals on their own accord began frequenting human campsites in search of food. Over time, they grew less inhibited, eventually becoming more domesticated and friendlier to man.
As the researchers point out, some 10,000 to 15,000 years ago, the Eurasian grey wolf evolved into a new species that was genetically identical to the modern dog. Evolution of different dog species has a relatively short history, with some dog breeds appearing only around 200 years ago. At present, Losey and his team at the University of Alberta are working at another dog burial site in Siberia.
With remains belonging to more than 100 different dog specimens, the site is believed to be home to the largest archaeological dog collection in the entire Arctic region. The researchers have found early remains of sled dogs, with harnesses attached to them. According to the archaeologists, the discovery points to a “multi-species community”, where humans lived and worked with dogs. Slightly puzzling perhaps is the evidence that suggests that humans in the area also ate dogs. Losey commented:
The big question in the field now is when and where exactly dogs emerged from wolves, but I don’t think that tells us very much,” he says. “What can we learn about people’s relationship with dogs in the past? The history of our working relationships with animals, and our emotional relationships, is what interests me.
Source: University of Alberta