A recent study, which examined the behavioral traits and genetic makeup of dogs and wolves, has revealed that our canine companions share a chromosomal overlap with humans who are diagnosed with Williams-Beuren syndrome. The researchers believe that it is precisely this similarity which sheds light on dogs' unwavering sociability.
Monique Udell, a scientist from Oregon State University, explains that "it was once thought that during domestication dogs had evolved an advanced form of social cognition that wolves lacked." However, she now feels that "this new evidence would suggest that dogs instead have a genetic condition that can lead to an exaggerated motivation to seek social contact compared to wolves."
Williams-Beuren syndrome is a terrifying developmental disorder which can alter people's facial features, as well as potentially causing a whole host of health issues, such as heart defects and abnormalities in the nervous system and brain. However, one of the most distinctive psychological symptoms of Williams-Beuren syndrome is hyper-sociability, which is primarily characterized by a severe lack of social inhibition and a high level of empathy. This is why sufferers are often seen to display an excessive amount of friendly and outgoing behavior, even towards complete strangers.
Along with a fellow evolutionary biologist from Princeton University, Bridgett vonHoldt, Udell observed striking parallels between the behavior of dogs and the hyper-sociability that's part-and-parcel of Williams-Beuren syndrome. That's why they then decided to find out just how closely they're related at the genetic level.
"It was the remarkable similarity between the behavioral presentation of Williams-Beuren syndrome and the friendliness of domesticated dogs that suggested to us that there may be similarities in the genetic architecture of the two phenotypes," vonHoldt explains.
To carry out their study, the two researchers took 10 human-socialized wolves and 18 domesticated dogs. They subjected them to a number of behavior-based experiments, which involved both new and familiar people to help gauge their sociability levels on an individual basis.
To nobody's surprise, the dogs proved to be far more friendly with humans than the wolves were, and they found that the main reason for this was a number of variations present within a region of chromosome 6 inside the dog's DNA sequences. To be specific, the many genetic insertions (called transposons) in the Williams-Beuren syndrome critical region (WBSCR) in the friendlier dogs appeared to affect a protein called GIF21, making them more sociable. The less sociable ones were found to have less of these disruptions, which is why they exhibited more wolf-like behavior.
VonHoldt said that they "haven't found a 'social gene,' but rather an important [genetic] component that shapes animal personality and assisted the process of domesticating a wild wolf into a tame dog." This could help to explain exactly how dogs and wolves became separated into two distinct groups during evolution.
Scientists had often debated whether dogs became social animals after wolves began to be domesticated by human beings. However, the presence of certain social variants in the wolves that were studies appears to indicate that even wolves have the capacity to be extremely friendly under certain circumstances. At this point though, we still wouldn't recommend letting a wolf lick your face!
