29 SEPTEMBER 2005
part
from tricking dogs into salivating when a bell rings, scientists have
not generally paid much attention to man's best friend.
But perhaps that's how dogs want it. Rather than live the life of a lab rat, most dogs would probably prefer to take walks, chew on fake bones and bark at prowlers, with maybe a little Frisbee-chasing or ball-fetching now and then. In return for their entertaining behavior and practical services, dogs are usually coddled by people and provided with sustenance and shelter. It's a better deal than a lot of poor humans get these days.
So
how do dogs manage to achieve first-class social status with an economy-coach
mentality? It's simple. Dogs have good people skills.
In fact, it's almost as though dogs can read human minds. "It appears that dogs have evolved specialized skills for reading human social and communicative behavior," write anthropologist Brian Hare and psychologist Michael Tomasello of the Max Planck Institute for Evolutionary Anthropology in Leipzig, Germany.
In fact, dogs seem to understand people better than closer, smarter human relatives do (such as chimps). Somehow, dogs have developed advanced social skills -- perhaps in parallel to the evolution of human social behavior itself, Hare and Tomasello suggest.
Several experiments have demonstrated canine skill at deciphering human communicative cues. When researchers hide food in one of several opaque boxes, and then look at or point to the correct box, dogs usually go directly to the box with the food (sealed tightly to block the smell).
Chimps fail miserably in similar tests, picking a box at random. But in most such experiments, more than two-thirds of the dogs score much higher than random guessing would predict. (It's no disgrace that some dogs didn't do so well -- some people can't follow directions, either.) And most dogs can interpret the human signals from the outset of the experiment, with no learning curve to figure out what pointing, gazing at or nodding toward a box means.
Other research reveals that dogs are aware of what humans can or can't see. Warned to stay away from tempting food, dogs obey while the human's eyes are open, but sneak toward the food when the human's eyes are closed. Put a barrier between the human and the dog, and the dog might go for the food -- unless there's a window in the barrier. (Even if the dog can't see the person, dogs know that people look through windows.)
Dogs themselves know how to express communicative cues. Though limited in language to grrr and woof, dogs are good at gestures and facial expressions. Given a locked box containing food, dogs quickly realize their limitations as locksmiths, and will begin shifting their gaze between the box and a nearby human.
Even young puppies possess most of these skills, suggesting that canine social skills are not learned, but ingrained into the species' evolutionary heritage. Such skills were not inherited from wolves, though (a wolf never asks a human for help in opening a box). Thus it appears that dogs evolved their social skills during the era of their domestication by people. As dogs and humans learned to live together, they learned to communicate with one another, Hare and Tomasello conclude in this month's (Sept., 2005) issue of Trends in Cognitive Sciences.
Domesticating dogs involved selecting those members of the canine species
with a human-tolerating temperament. 
During
the evolutionary process, dogs predisposed to fear or that bite people
would not be likely to earn the benefits of human companionship. Consequently
they would be at a survival disadvantage compared to those who would suck
up to humans for treats and protection.
Dog "sucking up."
"Dogs' skills for reading human social-communicative behavior might have initially evolved as an incidental by-product of selection for tame behavior," Hare and Tomasello write.
In other words, when dog brains evolved constraints on fear and aggression, cooperation with people became possible. And then, among the cooperator dogs were some who were also better communicators, and they got the jobs of helping people with herding or hunting. So a pleasant temperament may have been the prerequisite for gaining the survival advantages offered by communication skills, or "social intelligence."
The intriguing thing about this dog story is that it might apply equally well to people. "The evolution of the human temperament might necessarily have preceded the evolution of more complex forms of human social cognition," Hare and Tomasello suggest. "One might seriously entertain the hypothesis that an important first step in the evolution of modern human societies was a kind of self-domestication."
One big difference between humans and chimpanzees, for instance, is that chimps cannot control their fears or tendencies toward aggression, except in rare and specific circumstances. It's the human ability to engage in social cooperation and communication that underlies civilization itself. And such cooperation is possible only once a species learns how to constrain its aggressiveness and fear.
In many ways, it often seems, dogs have learned that lesson better than some people have.
Read more Science Matters
E-mail: tsiegfried@nasw.org
