A new study took a deep look into the anatomical structure of several dogs to discover whether their brains showed any significant variation across different breeds.
Every dog lover knows different breeds tend to act differently, at least in general. Chihuahuas are on average far more anxious than, say, Great Danes, and that's certainly not a coincidence. We already know dog breeds vary in shape and size and color, and we're at least vaguely aware that their behaviors are just as diverse. Some breeds were selected for hunting, whereas others were bred purely for their looks.
What we didn't know, though, is just how big a role we actually played across millennia in the deepest anatomical features of our favorite companions. As it turns out, we fundamentally altered their whole anatomy, including their brains. And that makes us responsible for a lot.
A penny for your canine thoughts?
Published Monday in the scientific journal JNeurosci, a new study showed just how varied the brains of our best friends are. The study was led by neuroscientist Erin Hecht, an assistant professor in the department of human evolutionary biology at Harvard University. “The first question we wanted to ask was, are the brains of different breeds of dogs different?” said Hecht.
For this specific study, Hecht and her team took a look at MRI brain scans of 62 purebred dogs from 33 different breeds. As soon as they compared the images before them, they noticed something: aside from varying in shape and size, the brains showed significant layout differences across breeds. This variation, Hecht pointed out, could not be explained merely by differences in mass. It's not just that the dogs were small or big, long or short—their brains are different well beyond that.
Sure, different breeds have different head shapes and sizes—hence different sizes of brains too. But that's not what we're talking about. Much more importantly, different breeds have different brain structures—that's something we didn't know until now.
That basically means that, above and beyond size, dog brains are wired differently depending on breed. Chihuahuas' brains aren't just miniature versions of Great Danes' brain—they have different connections and activities altogether.
Dog's brain is as dog's brain does
More specifically, the team identified six distinct brain networks whose appearance varied considerably from breed to breed. Hecht hypothesized that these regions were working together in different behaviors, leading to innate behavioral patterns that might have been artificially selected for (i.e. bred for).
So, the team set out to analyze these different networks based on these selective behaviors, and the results panned out. Each of the six regions was strongly correlated to at least one specific behavioral trait according to the specific breed and the purpose it was bred to fulfill. For example, dogs whose breed was used for hunting with sight showed significant more specialization in the visual areas of the brain, whereas breeds that were meant to hunt by smell displayed greater development in the smell-processing regions.
This last example is crucial: it's not that some dog breeds have a better sense of smell; it's that their brains can be wired to report that information in the first place. Even if a pug, say, can sniff just as well as a Bloodhound, the latter will be significantly better by nature at letting its owner know what it found.
There is one important limitation to this study, though. Hecht and her team studied pet dogs rather than working ones—meaning that they looked into the brain features of individual canines that had never really performed the tasks they were bred for, such as hunting. But the research isn't over.
On the contrary, this is just the first step into a previously unexplored investigation into canine cognition, and it's only going to get more interesting. Next, Hecht says she wants to study working dogs, which might show yet more pronounced and more definitive results overall.
The research can prove groundbreaking for understanding brain evolution more species, humans included. Here's hoping that happens.
Take a look at these other articles:
Sad Photos That Show How Humans Have Selfishly Deformed Dog Breeds
Frida, The Most Famous Rescue Dog In The World, Has Finally Retired
The Forgotten Animals That Made Space Travel Possible For Humans