Friday, September 05, 2008


The following paragraphs come from the next to last chapter of Edward Wilson's Naturalist. They detail his thinking as he tried to strengthen the evidence for his idea that human culture is not different than ant or monkey cultures. All cultures are heavily indebted to instinctual behavior for their structure and ants and humans share some of these cultural traits in common. It's some more of the science that makes me say that I'm a robot. His idea was attacked mightily when it appeared. Of course, you can see that he's not as much a reductionist as I am when I tell people I'm a robot.

By this time it was obvious to me that human sociobiology would remain in trouble, both intellectually and politically, until it incorporated culture into its analyses. Otherwise the critics could always cogently argue that since semantically based mind and culture are the defining traits of the human species, explanations of human social behavior without them are useless. This shortcoming was on my mind when Charles Lumsden, a young theoretical physicist from the University of Toronto, arrived in early 1979 to work with me as a postdoctoral research fellow. His interests had lately turned to biology, and he saw great opportunity in the analysis of social behavior. We talked at first about a collaboration on social insects, but soon our conversations gravitated to the subject of heredity and culture. I said, the possible payoff justifies the high risk of failure; let's give it a try. So two or three times a week for eighteen months we sat together and framed the subject piece by piece.

We reasoned as follows. Everyone knows that human social behavior is transmitted by culture, but culture is a product of the brain. The brain in turn is a highly structured organ and a product of genetic evolution. It possesses a host of biases programmed through sensory reception and the propensity to learn certain things and not others. These biases guide culture to a still unknown degree. In the reverse direction, the generic evolution of the most distinctive properties of the brain occurred in an environment dominated by culture. Changes in culture therefore must have affected those properties. So the problem can be more clearly cast in these terms: how have genetic evolution and cultural evolution interacted to create the development of the human mind?

No doubt we went out of our depth in embarking upon this subject. But so was everyone else, and no one can be sure of anything until the attempt is made. Undaunted then, we sifted through a small mountain of literature in cognitive psychology, ethnography, and brain science. We built models in population genetics that incorporated culture as units of learned information. We studied the properties of semantic thought to make our premises as consistent as possible with current linguistic theory.

We were looking for the basic process that directed the evolution of the human mind. We concluded that it is a particular form of interaction between genes and culture. This "gene-culture coevolution." as we called it, is an eternal circle of change in heredity and culture. Over the course of a lifetime, the mind of the individual person creates itself by picking among countless fragments of information, value judgments, and available courses of action within the context of a particular culture. More concretely, the individual comes to select certain marital customs, creation myths, ethical precepts, modes of analysis, and so forth, from among those available. We called these competing behaviors and mental abstractions "culturgens." They are close to what our fellow reductionist Richard Dawkins conceived as "memes."

Each time an individual modifies his memories or makes decisions, he entrains intricate sequences of physiological events that run first from the perception of visual images, sounds, and other stimuli, then to the storage and recall of information from long-term memory, and finally to the emotional assessment of perceived objects and ideas. Not all culturgens are treated equally; cognition has not evolved as a wholly neutral filter. The mind incorporates and uses some far more readily than others. Examples of heredity-bound culture that Lumsden and I found from the research literature include the peculiarities of color vision, phoneme formation, odor perception, preferred visual designs, and facial expressions used to denote emotions. All are diagnostic of the human species, all part of what must reasonably be called human nature.

Such physiologically based preferences, called "epigenetic rules," channel cultural transmission in one direction instead of another. By this means they influence the outcome of cultural evolution. It is here, through the physical events of cognition, that the genes act to shape mental development and culture.

The full cycle of gene-culture coevolution as we conceived it is the following. Some choices confer greater survival and reproductive rates. As a consequence, certain epigenetic rules, those that predispose the mind toward the selection of successful culturgens, are favored during the course of genetic evolution. Over many generations, the human population as a whole has moved toward one particular "human nature" out of a vast number of natures possible. It has fashioned certain patterns of cultural diversity from an even greater number of patterns possible.

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