More on the brain size debate: Part II

While we're on the subject of brain size, I wanted to share another interesting Temple Grandin theory. In Animals in Translation, Grandin suggests that we humans may be suffering from a species superiority complex. While she agrees that domestication was responsible for a 10 percent reduction in brain size in dogs, she contends that the civilizing process cut both ways. Taming wolves had a profound effect on the evolution of the human brain, according to Grandin.

Recent scientific findings suggest that human-wolf cohabitation began as long as 100,000 years ago. If these findings are correct, Grandin says:

Wolves and people were together at the point when homo sapiens had just barely evolved from homo erectus. When wolves and humans first joined together people only had a few rough tools to their name, and they lived in very small nomadic bands that probably weren't any more socially complicated than a band of chimpanzees . . .

This means that when wolves and people first started keeping company they were on a lot more equal footing than dogs and people are today. Basically, two different species with complementary skills teamed up together, something that had never happened before and has never really happened since.

(Animals in Translation, 304-306)

This is more than a nostalgic ode to the ongoing love affair between humans and dogs. If our interspecies relationship does, in fact, date back this far, Grandin (among others) thinks it may provide the key to understanding how humans developed the complex social networks and behaviors that allowed them to thrive:

During all those years when early humans were associating with wolves they learned to act and think like wolves. Wolves hunted in groups: humans didn't. Wolves had loyal same-sex and nonkin friendships; humans probably didn't, judging by the lack of same-sex and nonkin friendships in every other primate species today . . .

Wolves, and then dogs, gave early humans a huge survival advantage . . . by serving as lookouts and guards, and by making it possible for humans to hunt big game in groups, instead of hunting small prey as individuals. Given everything wolves did for early man, dogs were probably a big reason why early man survived and Neanderthals didn't. Neanderthals didn't have dogs.

(Animals in Translation, 304-306)

Not feeling quite so paternalistic towards little Fifi now, are you?

Or maybe you're finding it hard to accept the idea that wolves may be responsible for inculcating us with the more humane aspects of human behavior. You certainly wouldn't be the first. But before you dismiss Grandin's theory, consider this:

Archaeologists have discovered that 10,000 years ago, just at the point when humans began to give their dogs formal burials, the human brain began to shrink. . . It shrank by 10 percent, just like the dog's brain. And what's interesting is what part of the human brain shrank. In all of the domestic animals the forebrain, which holds the frontal lobes, and the corpus callosum, shrank. But in humans it was the midbrain, which handles emotions and sensory data, and the olfactory bulbs, which handle smell.

(Animals in Translation, 304-306)

To Grandin, this suggests that "dog brains and human brains specialized: humans took over the planning and organizing tasks, and dogs took over the sensory tasks."

Many scientists have greeted Grandin's theory as heresy. But, before you rush to judgment, stop and think. Why would you assume that a relationship powerful enough to influence the development of the canine brain, would leave the human brain untouched? Given what we now know about the brain's "plasticity," it makes sense that a synergistic interspecies relationship like this would leave its mark on both species.

We, humans, are so accustomed to being at the top of the evolutionary pile, we find it difficult to remember that this wasn't always the case. Us depend on dogs? Pishaw. But if you had to place a wager, who would you bet on to survive in the wild? A naked, pink-skinned biped with an oversized head and no sense of community, or a pack of mutually supportive runners with big teeth and built-in temperature control?