Given humanity’s many shortcomings, it’s good to know someone likes us – and new research suggests they may not have a choice. According to a study published yesterday in the journal Scientific Reports, dogs’ love of humans might be written into their genes.
Unlike other canines such as wolves, dogs are naturally sociable towards humans, which raises some curious questions regarding how they came to develop their affectionate personalities. To investigate, a team of scientists got hundreds of beagles to take part in a test in which they had to try and access food placed inside boxes with transparent lids.
Each dog was faced with three boxes, one of which had its lid bolted shut, making it impossible to get the food out. The point of the experiment was to see how long it took each dog to turn to a human for help, either by making eye contact or by running over to them.
Unlike dogs, wolves are known to persist on their own when faced with difficult tasks, yet dogs seem to have a natural tendency to depend on humans when they need a hand.
Some dogs were more reluctant than others to seek out help from their two-legged friends, which enabled the researchers to rank them in order of sociability. They then took DNA from the 95 dogs with the highest and lowest scores in order to analyze their genomes and determine whether any particular genetic traits could be attributed to a high or low affinity for humans.
They discovered that five genes, occurring in two different genomic areas, appear to be linked with a propensity for human contact. Interestingly, some of these genes are also associated with certain personality traits in humans too.
For example, a gene called SEZ6L was found to be associated with dogs’ dependence on people, and is also involved with autism in humans. Similarly, a gene called COMT is linked with aggression in adolescents, attention deficit hyperactivity disorder (ADHD), and schizophrenia.
Despite these results, study co-author Per Jensen told The Guardian that genes are probably only partially responsible for dogs’ love of humans, explaining that “the genetic contribution to this variation is only about 30%, so 70% of the variation has to do with things like experience.”