According to a study published in the scientific report on the 9th, the melanocortin receptor-2 (MC2R) gene may have played a role in the domestication of dogs, enabling them to develop social cognitive skills and interact with humans This gene is associated with the production of the stress hormone cortisol.
It is believed that changes in genes that normally control hormones that affect social behavior are also related to dog domestication, but it is not yet clear which genetic changes have occurred.
This time, scientists from the Department of veterinary medicine, mahbu University, Japan, used two tasks to investigate the social cognitive interaction of 624 domestic dogs. In the first task, the dog needs to decide which bowl has food under according to the experimenter's prompts, such as gaze, pointing or tapping. This tests dogs' understanding of human gestures and expressions. In the second task, dogs need to deal with a problem-solving test. They want to try to open a container to get food. In this task, the frequency and duration of dog watching the experimenter will be measured, which reflects the dog's social attachment to human beings.
The team divided the dogs in the experiment into two groups according to their breeds: the ancient group (composed of breeds that are genetically closer to wolves, such as Akita dogs and Siberian sled dogs) and the general group (all other breeds that are genetically farther from wolves). They reported that compared with the general group, the ancient group looked at the experimenter less in the problem-solving task, which meant that they were less attached to people. No significant variety related differences were found in the first task.
Then, the team looked for genetic differences related to human cognitive ability between the two groups, including oxytocin (OT), oxytocin receptor (OTR), MC2R and a gene called wbscr17, which is involved in Williams syndrome (characterized by excessive social behavior) in humans. The two changes of MC2R gene are related to the correct understanding of posture in the first task and the more frequent viewing of the experimenter in the problem-solving task.
The team believes that these findings suggest that MC2R may play a role in the domestication of dogs, making the stress level of dogs lower when they are around humans.