Dogs were the first species known to have been domesticated.
Just how the wolf and dog drew apart is a story that has gripped researchers for centuries. Now, scientists are tracking down new clues between genetics and behavior by comparing the genomes of dog and wolf, zeroing in on the relatively small sections of DNA that explain why dog and wolf pups may seem so similar, only to grow up to be so different.
Dogs, of course, become trusted human companions. You can let them lick your face without concern they may decide to rip it off.
Not so with the wolf.
Not that wolves are bad. They are just different, a point underscored by some recent research that got widespread media attention last year.
A lengthy report in The New York Times, for instance, noted that researchers must be extraordinarily careful when raising wolves to maturity for the sake of science.
Like a lion tamer, you better keep your wits about you when strolling around a wolf pen. Even after years of close interaction, when you are even slightly ill or injured, you better stay out, lest one of the wolves senses a chance to tear into you.
One question this raises — given the genetic code shared by both species — is just how much wolf might be left lurking somewhere inside the family dog. And by comparing the dog to the wolf, scientists hope to gain insight into the genetics of aggression, even if they never completely understand what drives predatory behavior.
The mystery crosses the frontier between science and folklore.
Many years ago, after two giant dogs killed a woman in San Francisco, I wrote a newspaper story about dog bites. We found that all the frenzied concern about big scary-looking dogs was a little off. It masked a real hidden danger: Small dogs, not tended closely enough, can be quite dangerous, too.
For me, ever since, I have always kept in mind the possibility that a little wolf might suddenly emerge from within even the cutest little cuddly puppy in the living room. So I will never allow a small child and a dog to be left alone.
Not that I’ve ever seen a well-socialized family dog morph into a vicious, heavy-lidded killer. Not even when the full moon peeks from behind the clouds. But I don’t intend to take any chances.
A wolf bearing down on you is a nightmare scenario that cuts deep. Jack London knew this. So did Allen Ginsberg. He didn’t name his epic poem “Hiss,” or some other nasty cat sound. He wanted “Howl” to announce a break from the behavioral restrictions of our square little uptight human world. It’s not just a tantrum. It’s the call of the wild.
Evidence for the divergence of dog from wolf is tentative, and that, too, is a reminder of what a dog really is. It’s a predator, a killer that takes advantage of weakness. Yet somehow we’ve managed to turn the dog version of the canine into a species that loves us so much it puts all that aside.
Some dogs are still pretty effective at scaring people. What’s the biological root of these behavioral tendencies? It’s one of the more intriguing questions in animal science, and potentially may point to some important clues beyond canines.
Some people, after all, may be similarly prone to aggression, and at least some of this may be heritable.
The friendly tendencies also are partly gene-linked. In any case, the dog’s rapid adoption of human-desired traits is fossilized in genomic data, which scientists are tracing back through the millennia.
Archaeological evidence suggests that dogs muzzled their way into human habitats at least 15,000 years ago. It took thousands more years for any other species to gain so much as a toe- or clawhold on human society. There may have been multiple “initial domestication events” all around the world. Dogs hitched a ride on the human gravy train early on, in a lot of places, more or less around the same time.
Domesticated dogs spread far and fast among the early nomadic tribes of modern humans. No matter what kind of hunter-gatherer you were, whether you hunted moose in polar bear skins or scraped together pine nuts in the desert, the dog turned out to be a useful companion for just about anybody. They’ve been coming along on camping trips and begging for leftovers ever since.
So we see the numbers today. Everywhere people sleep, dogs seem to be under, near or on top of the bed. There are something like 80 million dogs in the United States, by some estimates. Nearly 44 percent of U.S. households have at least one dog living there, compared with 35 percent with cats.
We spend on average $378 a year per dog on veterinary care, according to the American Veterinary Medicine Association. And I’m sure some people spend more than that on doggy bling on a single weekend in Palm Springs.
And one reason we love dogs so much is that they have something in common with the wolf, and yet keep it to themselves, so we can trust them.
To a point. Just remember the teeth are still pretty sharp.
Carl T. Hall, executive officer of the Pacific Media Workers Guild, is a longtime science reporter and journalism instructor who is allergic to cats. He lives in the Bayview neighborhood where he and some business partners will soon be opening a dog-friendly cafe, Word.
Main article photo by: Photo by istock/kjekol