The Unselfish Gene?

I remember a nature documentary I saw years ago. A pregnant lioness had strayed from her pride and was being tracked by a clan of hyenas. At night, the lioness hid in some bushes and gave birth to an infant cub. The hyenas were closing in. She abandoned her cub and tried to escape only to be killed later that night by roving male lions in an act of cannibalism.

The new born cub started crying in the bushes where it was hidden. A passing leopardess heard it and picked it up. She clearly wanted to care for the cub. But the hyenas were too close. She too had to abandon it and make her escape. Moments later, the hyenas found the cub and killed it.

Finally later that same night when the leopardess reached her own cubs. She found that one of her two daughters had been mauled to death by the lion pride.

That night demonstrated two sides of the question that has led to much debate and speculation amongst biologists.

In 1976, British biologist Richard Dawkins published the surprising bestseller titled the Selfish Gene. Naturalists had long observed both selfish and altruistic behavior in the animal world. They had grand ideas about how each individual was motivated by the idea of propagation of its species.

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The Selfish Gene

Dawkins’s book marked a turn in understanding. It showed that a lot of these behaviors could be explained if we just thought of them in terms of particular genes trying to survive and dominate. So animals would protect their own children or related children which shared their genes. They could even sacrifice their lives in an emergency. According to the new viewpoint this was because their children had a higher chance of propagating their shared genes than they do themselves.

All instinct and behavior was therefore governed by the imperative to preserve and propagate the genes that made the organism. The life of the individual was irrelevant in this scheme. Genes regulated behavior. Genes that promoted behavior that allowed that gene to survive thrived while others died out. All life was but automatons, a means to an end for the gene to grow.

Recently though, the body of facts that don’t fit into this neat theory is growing. Oddly enough, much of it is coming thanks to new technology developed for paternity testing. Studies were done of Australian birds who spent tremendous time and energy getting food for their chicks and among chimpanzee tribes where parents cared for children. This seemed to fit pretty well in the selfish gene narrative except that when they checked the genes of the animals, they found the infants were often unrelated to the parent caring for them.

There is no mechanism in the selfish gene theory by which an animal would knowingly care for infants that don’t share its own genes (we are not considering the case where the parent is duped as in the case of cuckoos). This is especially true in adverse situations where nurturing unrelated infants could mean the parent would be able to provide less nourishment for its own children. Yet it seems that such things do happen.

So what is the answer, is all life merely a carrier of its genes? Or is there more to it than that? Things are more complicated than they seemed a few years ago.

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