With a joint evolution spanning tens of thousands of years, the relationship between dogs and humans is considered one of the most remarkable in the history of our species.
Dogs, as guardians of flocks and herds, contributed to the transition to sedentary societies and to the promotion of agriculture and livestock. More recently, they have, in many cases, become true members of the human family.
The success of this relationship rests, in a sense, as with any other relationship, on the capacity for communication and the recipient’s ability to understand, even if only in broad terms, the sender’s message.
A new investigation reveals that dogs, along the course of their evolution alongside humans, have developed “exceptional communicative abilities”, both through adaptations promoted by the selective breeding pressure we exert on them and through their individual capacity to learn.
In the journal The Journal of Neuroscience, three researchers from Harvard University (United States of America) studied the functioning of the brains of 108 dogs to try to discover how this co-evolution altered the capacity and neural activity of canids. For this, they used non-invasive 3D imaging techniques.
The team found that selective breeding for better integration of dogs into human working and family lives altered neural pathways related to communication, compared with those of older dog lineages. The researchers say that these changes are clearly visible in neural pathways associated with the processing of vocal cues and language.
When comparing the brains of trained dogs to perform specific functions with those of canids with similar reproductive histories but without that training, it was found that training alters the strength of neural pathways related to the ability to interpret cues or signals and to execute responses.
The trained dogs also showed stronger connections between brain areas associated with the ability to respond to others’ communication.
The researchers consider that this work suggests that genetic selection through reproduction and the individual experience of each animal shaped the dogs’ communicative abilities.
“I think this research can help us understand not only dogs, but also the human-dog relationship,” says Mélina Cordeau, the study’s first author.
“By identifying how dogs process human communication and how reproduction and training shape these abilities, we may, perhaps, come to improve the way we interact with dogs, refine training approaches, and make the training of assistance dogs more effective and better suited to each individual dog,” she explains.
