By Lin Zhang
As I drag myself home from a long day of school, exhausted and worn out from studying for a genetics test the night before, I receive a pleasant surprise. A woman and her corgi walks in my direction, with the corgi desperately pulling at its leash trying to approach me. I immediately wake up from walking like a zombie and enthusiastically kneel down to pet the friendly animal. The dog seems to like me a lot, I think proudly to myself. After this encounter, I smile for the rest of my way back home.
Most dogs are known to be unusually approachable, but have you wondered exactly what makes them more friendly than other animals? It’s NOT necessarily because they are particularly attracted to you. Rather, dogs’ friendliness stems from their genetics!
Ever since their domestication thousands of years ago, dog genes have been evolving in parallel with human genes, largely driven by the shared environment between the two species. Gradually, their wolf ancestors evolved to have floppy ears, wagging tails, and friendly personalities, and dogs became human partners and household pets. There’s a saying that a dog is a man’s best friend. Indeed, they are loyal, caring, and affectionate companions. Now, science has found that there is actually a genetic link to the friendliness of dogs.
A study titled “Structural variants in genes associated with human Williams-Beuren syndrome underlie stereotypical hypersociability in domestic dogs” conducted by the Department of Ecology and Evolutionary Biology at Princeton University compared the behavior of human-raised dogs and wolves. The study revealed that genetic variations in dog chromosome 6 was responsible for hypersocialiaty. Hypersociability is a phenotype which consists of heightened proximity seeking and gaze, higher oxytocin levels, and hindering of independent problem-solving behavior around humans.
Dogs were observed to spend a greater proportion of time gazing at humans instead of trying to solve a puzzle box when compared to wolves. Evidence showed that mutations in the GTF2I and GTF2IRD1 genes are associated with sociability in dogs. These genes encode for a phosphoprotein that binds to the initiator element in promoters to regulate transcription. Variants of the same genes are known to cause the Williams Syndrome in humans associated with highly social personalities.
The next time you see a dog, you will know that their genetics actually contribute to their friendliness towards you. Although friendliness of dogs might be a favorable trait to humans, one might ask whether domestication was beneficial to dogs. Is it selfish of humans to restrict an animal’s freedom for their own pleasure or want of a companion? Is it ethical to breed dogs for desirable traits? Drawbacks of inbreeding includes the increased chances of recessive mutations and limitations of genetic diversity of many breeds.
But be aware, not all dogs are friendly unconditionally. Demonstrations of threat might provoke otherwise friendly dogs to attack in order to protect themselves. For example, a common misconception that people have is that all bulldogs are aggressive. Rather, bulldogs are naturally loyal and affectionate. The root of bad behavior from any dogs can be tracked down to their training and their owners. If an owner of a bulldog treats it aggressively, then it will become improperly aggressive when threatened. With their powerful jaws and overall image, bulldogs built up the reputation of being hostile when they are actually the opposite. There is no justified reason for humans to blame dogs when the root of the problem stems from their own misconduct.
Even though dogs have different degrees of friendliness, you can rely on them to be
loyal, compassionate, and energetic companions. To reciprocate, owners have an obligation to treat them with respect and care. If you want to own or adopt a pet, consider the responsibilities that come with it. You might regard a dog as just another part of your life whereas to them, you are their only one.