Several North American institutions have joined in a study to analyze the genes of current dogs and thus be able to expand knowledge about the relationship between breed and behavior. This issue, despite the preconceived ideas that exist around certain types of dogs, was not yet developed.
The hunt: that abyss of shadows
The scientists used genome-wide association studies to search for common genetic variations that could predict behavioral traits in 2,155 purebred and mixed-breed dogs. They then combined this data with 18,385 surveys of pet owners from the Darwin's Arkan open source database of owner-reported canine traits and behaviors.
“For some traits, we found genetic variations that are significantly associated with behavioral differences. The most notable includes a region of DNA linked to howling frequency. It is not within a gene, but rather it is together with another possibly regulatory one, and that, in the case of humans, if it does not go well, it affects the area of speech development in the brain", explains Kathleen Morrill, main author of work at the University of Massachusetts Medical School (USA).
Until now, behavioral genetics in dogs has focused on modern breeds, isolated subgroups with distinctive physical and, presumably, behavioral characteristics.
In the study, behavioral data was analyzed based on owner-declared breeds and genetically detected racial ancestries.
Race explains only 9% of behavioral variation
The results of these tests, which included data from 78 breeds, identified eleven specific chromosome locations strongly associated with behavior, although none of these were breed-specific. Only 9% of the behavioral variation of individuals was linked to it.
The team proposes that behaviors perceived to be characteristic of modern breeds "derive from thousands of years of polygenic adaptation prior to breed formation, and that modern breeds are primarily distinguished by their aesthetic features."
“Most of the behaviors that we consider characteristic of modern dog breeds are the result of thousands of years of evolution, from the wolf to the wild dog, through the domestic dog and, finally, to modern breeds,” says the co-author, Elinor Karlsson.
Behaviors associated with genetics
One of the behaviors that genetics most predicted was the ability to respond to human cues. However, this varied significantly between individual dogs.
“We are not referring so much to the training capacity itself, as to the motivation to carry out orders. Docile dogs are internally motivated, that is, eager to please people. On the contrary, those who are more independent may be more externally motivated (through treats or toys), they need you to make it worthwhile for them. Both are traits that can be trained, but more autonomous dogs may need more positive reinforcement, "says Morrill.
As an example, the researcher puts a breed that seems, on average, more independent, such as the Great Pyrenees. Her population is from working dogs (livestock guard dogs) so it would be wrong for her to say they are not 'trainable' or not intelligent. Rather, they are more independent.
Environment and experience were shown to be a huge component in determining dog behavior
“Environment and experience were shown to be a huge component in determining dog behavior. In addition, age was significant for several traits such as toy practices, and sex for only one trait: the 'raise paw to urinate' command, but that may be because there aren't many unneutered or unspayed companion dogs , or specifically in this study”, continues the author.
They also found differences between pure and mixed breeds. The genomes of mongrel dogs were more complex and their levels of inbreeding lower than those of purebred dogs, although that was an expected finding. “What is surprising is that both, together, are useful for the genetic mapping of these characteristics. Previously, scientists almost always focused on purebreds, thinking that the DNA of mongrels would be too complicated. New statistical methods and genomic technology have made the latter feasible in studies”, he stresses.
Modern breeds since the 19th century
Despite being one of the oldest animal companions of humans, almost all modern dog breeds were created only about 200 years ago. Before that date, more than 2,000 years ago, dogs were selected mainly for traits essential to their functions, such as hunting, protection or herding.
Despite being one of the oldest animal companions of humans, almost all modern dog breeds were created only about 200 years ago
It wasn't until the 19th century that humans began to select dogs for their breed-defining physical and aesthetic traits. Today, most modern dog breeds are attributed characteristic temperaments associated with their ancestral function. For this reason it was assumed that the racial ancestry of each dog predicted its temperament and behavior.
Should the legislation change?
This has led to, among other things, a series of breed-specific legislation, which may include insurance restrictions or outright bans on owning some breeds of dogs.
“Although we do not provide any statements on laws directly in this study, it does highlight that general statements about race that assume it is predictive of individual behavior is a flawed approach,” Morrill concludes.
Kathleen Morrill el al. “Ancestry-inclusive dog genomics challenges popular breed stereotypes”. Science