Why Do Dogs Bark?

Why Do Dogs Bark?

It may seem like a silly question at first. Dogs bark because… well, “dogs are dogs, and that’s what they do.” Could you imagine the UPS guy coming to your door and your dog not barking? But doesn’t it seem interesting that adult wolves, ancestors of modern-day dogs, hardly ever bark? They may howl, growl or even “yip,” but they certainly don’t bark the way dogs do. Wolf puppies, however, do bark. And this fact offers a key to understanding something about the nature dogs, and why we humans are so bonded to them.

In Siberia, over 50 years ago, a Russian geneticist named Dmitri Belyaev wanted to better understand how and why the behavior and physical characteristics of domesticated animals differed from their wild counterparts. In a now famous experiment that spanned decades, he studied a captive colony of Arctic foxes. Belyaev observed that as these wild foxes were selectively bred for tameness over several generations, other characteristics changed profoundly too. Hair color changed, as well as reproductive cycles. Noses became more rounded; and upright, pointy ears started to fold over. These foxes actually enjoyed the attention of humans, unlike the foxes at the start of the study who behaved—understandably—like wild animals.

So what does this tell us about “man’s best friend?” Basically, it suggests that dogs are genetic adolescents, never maturing into a full adult stage. Scientists use the term “neotony” to describe
a condition in which adults retain characteristics of a juvenile. In the evolution of dogs, the wolves that were more “tame” got more access to human food leftovers, and were thus better nourished and more likely to breed successfully. Because human interaction selected wild canines for tameness, a behavior trait of immature animals, we also unintentionally selected for other puppy-like characteristics.

Take for example, a Great Pyrenees, one of the giant guard dog breeds. They look like huge puppies with rounded faces and floppy ears. They act like puppies, preferring to lounge in their “dens” venturing out only briefly to check out a strange sound, and bark. This behavior is, by the way, what we want guard dogs to do. The Blue Heeler, on the other hand, herds livestock by chasing them and nipping at their heels (thus the name “heeler”). This is a more genetically mature breed, displaying behaviors we would expect from an older wild predator. Herding breeds also have the upright pointy ears and longer, sharper muzzles characteristic of fully matured canines.

Another example of genetically selected immaturity is the Pug. One reason it’s such a popular breed is that they look like human infants. Many people are attracted to breeds like the Pug because their physical features are, simply put, cute: rounded face, big eyes and totally non-threatening. Others prefer dogs that retain more developed characteristics such as German Shepherds, whose predatory instincts are essential for police-dog work.

No matter what breed, the modern dog is a product of millions of years of interaction with humans. This relationship has resulted in an animal that thrives on human companionship,
protects and serves humans in innumerable ways, but also… barks.