There are significant differences between the different dog breeds, not only in appearance but also in their personality traits. Some dogs are known for their loyalty, while others can boast intelligence as one of their best traits. Similarly, there are breeds that hardly shed, and others that are well-loved due to their facial features. On the other hand, some dog breeds also have undesirable traits, such a genetic predisposition to certain health conditions, coats that shed excessively, or an aggressive streak. This is why some breeds are better suited to jobs than others. So German Shepherd dogs work with the police, Border Collies are often farm dogs, and Pekinese are good companion dogs.
To breed dogs that have the best traits of a breed without undesirable traits, a process called selective breeding is used. Wikipedia describes selective breeding as a process that allows breeders to selectively develop specific characteristics. This is done by choosing the best dogs of one breed or mating two different breeds together to get the best traits of both. In the case of the latter, this is how designer breeds are created, such as Labradoodles.
The main advantage of using selective breeding is that it is possible to eliminate undesirable traits and reduce the likelihood of a dog suffering from a genetic condition that is associated with a particular breed. However, there are also some disadvantages. For example, Tree Hugger highlights the problem of breeding purebred dogs that are linked to certain health defects. In some cases, it can actually increase the risk of a dog suffering from a genetic condition rather than reducing the risk. There is also some evidence to suggest that dogs bred through selective breeding have shorter lifespans than dogs that are not bred in this way.
Now, there is evidence from new research that suggests that selective breeding is also changing dogs’ brains. According to I Heart Dogs, a team of researchers began a study to uncover whether there was a neurological basis for dogs having different physical and personality traits. The intention was to compare different breeds and identify if there were differences in their brains. For example, it is known that some dogs are excellent herders while others are known for their ability to sniff hunt. The researchers wanted to know if the brains of sniff hunters differed in any way from the brains of herding dogs.
Prior to this research, it was an area that had not previously been the subject of research. Therefore, very little was known about the differences in dogs’ brains and the researchers were unsure of what their results would reveal. One method that they used to identify any differences during their research was MRI technology. MRI scans were taken of 62 dogs, with the cohort including both male and female dogs of 33 different breeds. One thing the authors of the study were looking for was whether selective breeding had altered the organization of dogs’ brains and in what ways, if any, this had changed their brains.
Using independent components, the researchers analyzed the whole brain of each dog. One of their findings from doing this was that there were significant variations between one breed and the next in their specific regional sub-networks. Some variations that were noted were skull size and brain size in relation to total body size. This finding was not unexpected. However, they also find other variations that were a little more surprising.
Phylogenetic analysis was used to look closely at the variations. Using this method showed the researchers that the terminal branches at the top of the phylogenetic tree were the areas where most of the changes had taken place. This means that in terms of evolution, the changes have taken place recently and that human selection in individual breeds is likely to have contributed to this. As part of the selective breeding process, breeders have chosen dogs because they exhibit certain traits that are desirable for their needs. The way in which these dogs have been chosen has led to changes taking place in the brain. These changes have occurred over a relatively short timeframe.
Erin E. Hecht, one of the authors of the study, is an assistant professor in the Department for Human Evolutionary biology. In an interview with Newsweek, Hecht explained that the results showed that selective breeding by humans is at the very least partially responsible for the changes. She went on to describe how the studies have revealed that the changes to the brain organization of various breeds show that input from humans can cause changes in dogs’ brains to occur very quickly in relation to evolution.
These findings are significant as it shows the impact that humans can have on other species, both for good and bad. Hecht notes that a human’s ability to change another species is profound. She then went on to make further interesting observations from the research. Hecht notes that the dogs that took part in this study were not working dogs in roles that are associated with their breed. All the dogs that were subjects in the research are just normal family dogs. This is a relevant point because it shows that behavior and skills associated with a role are not learned by the breed, they are hardwired into the breed’s brain.
She explained this further by saying that kit was possible to see the specialisms of a breed in their brain, even if the dog does not perform those skills in their daily life. In her opinion, it is possible that they could see even clearer results if they included working dogs that actively perform certain skills in their studies. It is this belief that has inspired the next stage of the study. The team is planning to extend their research to working dogs that actively perform the skills associated with their breed to see if they can achieve even better results.