Rockets, Redheads & Revolution by James P. Hogan

Author:James P. Hogan
Language: eng
Format: mobi, epub
Tags: Collection
ISBN: 9780671578077
Publisher: Baen
Published: 1999-04-04T06:00:00+00:00

Evolution Revisited

A characteristic of good science, we’re told, is the ability and readiness to change one’s mind when the circumstances seem to call for it. One day, when my agent, Eleanor Wood, Jim Baen, and I were still considering a reissue of Minds, Machines and Evolution, I called Jim and said that if we decided to go ahead, maybe we should leave out “The Revealed Word of God.” Jim asked why. I explained that the assured zealousness with which I had pressed the Darwinist case when I wrote the piece back in the mid-eighties was somewhat embarrassing to read now. A decade later, I was less sure. Jim was interested and curious to know why. So, he thought, would quite a lot of other people be. Instead of taking it out, he suggested leaving it as it was and saying something about the reasons for having second thoughts, and then elaborating further on them in a piece to be written for this volume. So here it is.

To be clear at the outset, I’m not arguing about whether or not evolution happens. Life today is clearly very different from that of long ago. What I am beginning to doubt is the orthodox account we’re given of how it happens – specifically, the mechanism of random mutation and natural selection as the driving force responsible. I’m not even saying that selection doesn’t happen. It demonstrably does, and it has its results – but within limits, as plant and animal breeders know well. When domesticated animals return to the wild state, the most specialized are quickly eliminated and the survivors revert to the wild type. Selection is overwhelmingly a conservative force, preserving existing types by culling population and diluting away variations to prevent the kinds of extremes that human breeders encourage. The fossil record shows periodic epochs of profuse radiation and diversity of life forms appearing and subsequently being thinned down as the unfit, or the unfortunate, proceed to die out. (For a discussion of the relative merits, see David Raup, Extinction: Bad Genes or Bad Luck? W. W. Norton, 1991.) But this is exactly the opposite of the gradual increase of variety from a few ancestral types that the theory of diversification via natural selection predicts.

The effects of genetic mutations are nearly always harmful, but occasionally they do slightly improve an organism’s ability to survive and reproduce. And this one fact, although it has never been observed to produce a single new species, is the basis for attributing to the process the innovative and creative power to build, starting from molecules, all of the wonder and diversity that makes up the living world. An example proclaimed in practically all the textbooks as proof of the principle in action is the case of the British peppered moth, which tends to settle on the bark of trees. Where trees in industrial areas became darkened by pollution the dominant coloring of the moth population shifted from light to dark, whereas in untainted rural regions it remained light – in both cases affording better camouflage against predatory birds.

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