Evolution

EVOLUTION: THE TRIUMPH OF AN IDEA
By Carl Zimmer

At the dawn of the twenty-first century, Charles Darwin is on a roll.

“If I were to give an award for the single best idea anyone has ever had,” writes philosopher Daniel Dennett, “I’d give it to Darwin.” In his history of art and ideas, A Terrible Beauty, Peter Watson makes evolution the master narrative of twentieth-century thought. In a recent survey sponsored by Philosophers’ Magazine, Origin of Species was named the third most important philosophical work ever written.

And now, as a companion to the Public Television series “Evolution,” comes this lavishly illustrated book documenting the triumph of the idea of evolution, and its continuing importance as a scientific fact.

The notion that species evolve has been with us for a while. Even Empedocles had a rough idea of how natural selection worked. The discovery of a scientific basis for it in the mid-nineteenth century was inevitable, with or without Charles Darwin and his famous voyage on the Beagle. Another British naturalist, Alfred Russel Wallace was working his way toward much the same conclusion at the same time. When Thomas Huxley, “Darwin’s bulldog,” read Origin of Species he is said to have remarked, “How extremely stupid not to have thought of that myself.”

Today, the idea of evolution may be more important today than it has ever been. Hence the rush of accolades for the “best idea, ever.” One suspects the recent completion of the human genome project, with the sense it has given us of standing on the threshold of great advances in reproductive science, has something to do with all of the attention it has been getting. But talk about evolution has always been of more than scientific interest.

Evolution is genetic change that occurs over time. Changes are passed on through reproduction to future generations that experience improved survival rates. It is this process of natural selection that leads to differentiation among the species of life on Earth.

Take away natural selection, and what you have left isn’t a theory of evolution so much as a cultural metaphor. This is an important point because ever since Darwin there have been people wanting to transplant his ideas into other fields. Since evolution addresses such basic human questions as who we are, how we got here and where we may be going, this is easy to understand. But it isn’t science.

In the nineteenth century, for example, evolution was comfortably equated with historical progress by thinkers from across the political spectrum. Marx wanted to dedicate the second volume of Capital to Darwin, while “social Darwinist” proponents of laissez-faire capitalism read into his work a natural law justifying social inequality and the suffering of the poor.

Carl Zimmer takes exception to social Darwinism, arguing that it took “natural selection out of its proper place in biology and put it in a social environment.” But Zimmer’s text shows some of the same confusion. In one chapter he speaks admiringly of the infant science of “evolutionary computing.” But how can such “artificial evolution” really be considered evolution at all, even if we can imagine a species of “independent robots” able to design themselves? Isn’t this taking natural selection “out of its proper place in biology”? And what about “cultural evolution” and “evolutionary psychology”? Isn’t a lot of this just the old social Darwinism in borrowed clothes?

We might put the question this way: In a world where culture may be seen as having replaced nature as our environment, to what extent will our future evolution be necessarily self-made? As Zimmer points out, we can already see many examples of ways in which the old, biological evolution is being shaped by cultural evolution’s advance. Differences in reproductive success and the isolation required for genetic diversity may already be things of the past. Meanwhile, biologists like Edward O. Wilson (the man Tom Wolfe calls “Darwin II”) have begun to speculate about the possibilities of “volitional evolution” and the future of genetic engineering.

The line between culture and biology is a blurry one. In The Winter’s Tale, Polixenes defends the practice of breeding artificial flowers by making the point that art is man’s nature. It may not be unnatural for evolution to become an art.

Notes:
Review first published October 13, 2001.