GENETICS PLUS TIME

Conversation : LIFE

GENETICS PLUS TIME

A Talk with Steve Jones [3.26.00]

Steve Jones is a highly regarded geneticist and snail biologist. He is interested in why so much diversity exists in animals and plants: why no two individuals are alike. Surely, it can be argued, natural selection should instead inevitably lead to the evolution of one perfect form for each species. He works on the striking variety of shell color and banding patterns in the land snail Cepaea nemoralis. Cepaea has been seen as an archetype of diversity since the nineteenth century. In the 1950s, the English biologists Arthur Cain and Phillip Sheppard argued that such apparently trivial differences were under the action of natural selection (in this case because birds would attack the conspicuous forms). Jones finds that climate is also involved and — most important — that differences in microclimate on the scale of a few inches can alter the behavior and survival of snails of different pattern. Ecologically complex habitats hence foster genetic diversity. Jones has been writing and lecturing about science to a general audience for fifteen years. His book, The Language of the Genes won the 1994 Science Book Prize.

STEVE JONES: The small questions I'm asking myself have to do with genetics of snails and fruit flies. Not, I suppose of much general interest. However, they're a sub-set of a larger question which is, "Is life simple?" And the answer is probably more simple than you would have imagined, because the rules of evolution are straight-forward, and most attempts to bend or modify them have in the end turned out to be fairly unnecessary. It does look as if Darwin was, more or less, right. Most new discoveries fit well into his ideas. At the end of the century biology looks like a more straight-forward science than it did even 20 years ago, which I find a bit surprising — because, to the public, life seems fundamentally a mess. Of course, if you concentrate only on the details they get more and more complicated. The DNA sequence is more of a mess than anyone would have ever imagined; It's not a pretty sight. But descent with modification, as Darwin put it, or genetics plus time, as we can rephrase him today, is still the foundation of life. Biology is not like physics; Newtonian physics is in a deep sense wrong, whereas Mendelism and Darwinism are in a deep sense right.

JB: What are you trying to do to persuade the public of that?

JONES: I've had the rather daring — some people might say arrogant — idea of rewriting the Origin of Species itself, in my new book Darwin's Ghost. The idea was to take what Darwin called his "long argument" and reconstitute it with the facts of 1999 rather than 1859. As I say to annoy my publishers, it may be a rotten book, but it's a great idea — and I was amazed how well Darwin's argument stood up. We're thinking of special pitch-impregnated edition for sale in Kansas so that it burns well, but it would be nice to think that a few creationists might read it before they condemn it to the flames. However, the difficulty with arguing with anti-rationalists is that they're not susceptible to rational argument. People like Steve Gould have done a noble job in trying to apply rational argument. But most of them really will not be persuaded by whatever facts you present them with so that perhaps my book will have zero effect on them.

The odd thing about the Kansas fuss — and the whole creationist movement in the States, is how new it is. People always assume that when the Origin was published — just around the corner from here — the streets ran with blood, city blocks burst into fire, churches collapsed and hundreds hanged themselves in despair.

Of course, that wasn't true at all. There was some earnest debate among intelligent people and by the end of the 19th century most religious people, both here and in the States had managed to come to terms with Darwin. They had two approaches each of which was in its own way sensible. One was to say that the Genesis story was a metaphor and every day represented millions of years old. The other came from Wallace; that the six days were real — but they were the days in which God put into humankind, uniquely, a sort of post-biological soul, which didn't need genes and didn't leave fossils. Most religious people are happy to accept that and the Pope himself has recently come up with a very similar claim. Not until the 60s did hard-line creationism come back to life, and mainly in the States. Why that should be isn't clear to me at all. It has a political agenda in that most creationists are on the right, and wish to believe that there is a conspiracy by the left against them. If people of liberal persuasion believe in evolution then evolution must be wrong. But of course science, any science, isn't like that; it doesn't matter who believes in it, what matters is if it's true or not. And I have to say, evolution is true, no mind what millions might think. But why it is there's been a sudden outburst of antirational mania I don't understand. Maybe only an American can understand it.

JB: How has the evolutionary idea itself evolved?

JONES: It has, in fact, evolved in some quite unnecessary ways, because if you look back on many of the evolutionary controversies of the last 30 years, they really have ebbed away as knowledge has grown. Take punctuated equilibrium, which was a useful controversy as it made biologists feel less smug about their understanding of evolution. Or the lengthy argument about co-adaptation, the idea that genes didn't work as individual particles but as harmoniously interacting universes, and that this slowed evolution down because it was hard to get from one point to another. Or Sewall Wright's great idea that most evolution happened by accident, when you went through small bottlenecks, simply because natural selection could never get from one form to a new one without going through maladaptive forms on the way. 

Most of what seemed inexplicable fits, we can now see, into orthodox Darwinian theory. People have been inspecting Darwin's feet for signs of clay since the day he died. And although some traces have been found what's amazing is how well his edifice has lasted. Most of these evolving evolutionary ideas have gone extinct while the original one flourishes. The only important evolutionary piece missing in 1859 was the mechanism of inheritance, but once that appeared the edifice became so sound that much of what we've been arguing about has probably been fairly irrelevant.

JB: What is there about the public's understanding of science that can lead to Kansas and creationism?

JONES: The better the scientist, the narrower the mind, is a good general rule. And that's what science is, it's a collation of narrow minds all put together. Very occasionally we get a more open thinker (and I would put Gould into that category) who can see a pattern missed by the broad church of cramped imaginations. The great problem with the public understanding of science, and this shows in Kansas as much as anywhere else, is not to see that. People have no insight into what you might call the grammar of science, the way it works. Many people feel that because science is filled with disagreement it must be wrong. But it's not like religion, which is filled with agreement, at least within one faith. Again, unlike religion, we tend not to talk much about the stuff we agree on and concentrate on the difficulties. That, though, is a sign of strength and not weakness. Any science in which everyone agrees about everything is dead. Compare that to faith in the Bible story of creation!

JB: Darwinism remains a big subject in the United Kingdom. Books on Darwin are often at the top of bestseller lists while the same books published in the United States may receive scant review attention and come and go with little notice. Is this because Darwin is a home-town boy?

JONES: There's elements of that. Darwin was on the 20-pound note. You saw his face every day. He is a home-town boy; he's an iconic figure in Britain. And he's really fed into everybody, not only as a wonderful scientist, but as somebody having an exciting and interesting life. Any school kid can tell you what the Beagle voyage was. And he comes across as such an attractive character, which helps. That's why so much of the best science writing is about evolution. Where are the Goulds or Pinkers when it comes to the chemistry of chlorine? I'm sure it's just as interesting, but as far as I know there is no King of Chlorine around whom you could weave the tale.

JB: What do you think about the emerging field of evolutionary psychology? 

JONES: I find myself a bit depressed by the whole thing — a lot of it is the bland saying the banal. Of course, certain aspects of human behavior descend with modification from the past. About half of all genes are switched on in the brain and its foolish to say that those genes are different from all others, they can't evolve. It's clear that we descend from social primates and it's no accident that the worse punishment second to the death penalty is solitary confinement. If we descended from orangutans, which are rather solitary, the worst punishment would be to force someone to give a dinner party. So there is an evolutionary psychology in that sense, obviously.

But the problem is obviousness disguised as insight. There's plenty of good work on, say, the rate at which stepmothers kill their children; that's respectable social science. But I have to say I am not very surprised to find that mothers love their children more than stepmothers do. But evolutionary psychologists leap on the tables and shout we've made this fantastic discovery, equivalent to the double helix — mothers love their children! I say, what? And men are more violent than women. Well, I kind of knew that already. It's true, but it's not very profound.

And then there's this huge penumbra of pseudo-science around the subject. It's what I think of as neo-creationism. In Kansas nothing can be explained by evolution; it's wrong. That's it. To a lot of evolutionary psychologists, though, everything in human society — war, peace, rape, marriage, the lot — can be explained by the pressure to pass on genes. But if everything can be explained, then nothing can be explained. You don't need any experiments, it's in the great Darwinian Bible. I've seen evolutionary explanations of acne, of gossiping, of ballroom dancing, the lot. It's a parlor game called name and explain. Just as for creationists, all this needs nothing more than belief. The infantile Darwinists are in a situation where they can't lose. If you find everything in the Bible or the Origin there's no point in doing science.

Evolution is to social scientists as statues are to birds. It's a convenient platform on which to drop ill-digested ideas. An odd thing about evolutionary psychology — which is what most of the public (and, as I know to my cost, quite a few book reviewers) see as the centre of the science — is that it is almost absent from the practice of evolution itself. It may be talked about in psychological conferences, but it is never mentioned in evolutionary meetings. I go to dozens of them. People argue about the fossil records, about DNA, about animal behavior, about kin selection, about the nature of species — everything is open; but evolutionary psychology is, in the eyes of evolutionists, more or less a dead duck. I've never seen any of its supporters at a scientific meeting about evolution, either. There's a kind of parallel Darwinian universe in the arts faculty out there — and I don't think the arts faculty has much useful to say about science.

JB: What are you trying to accomplish with Darwin's Ghost?

JONES: I'm doing it in part for Dr. Johnson's reason, which is that no man in his right sense has ever written except for money. But I also did it because there was a gap that needed to be filled. There's a lot of good writing about evolutionary biology, but there's no good single book about evolution. Gould writes passionately and well about fossils; Dawkins about natural selection; Pinker about behavior; Diamond about our own biological past — but every one of those topics is only a small part of the story of evolution, and only one chapter (and for humans not even that) in Origin of Species.

Many years ago myself and some colleagues thought we might write an evolution text. And I had the bright idea as to how to write it — it was to take Origin and say, okay, this is what the story is; why don't we just use the same logic and put modern facts in. As soon as we started it became obvious that this was not going to be a book but a library; it would be the same size as Biology, it would be enormous, everything from Aristotle to Zoos. So it sat in the back of my mind for 20 years, and then I started doing it on a much smaller scale. The big problem was to know what to miss out. However, it amazed me how well the structure of the original Origin holds up. It has a narrative flow and a structure, and all the discoveries of today bolt onto it extraordinarily well.

JB: Where do you see the biological sciences going in the near term?

JONES: The immediate future is one of introspection. There's already the flapping of wings as the molecular chickens come home to roost. Five years ago the optimists were saying that we will soon cure genetic disease. They've been remarkably silent the last 12 months, and they're going to be a lot more silent two years from now. The great unachievable, the human genome sequence, isn't actually answering many questions. Instead, it's asking them. And the hope of an immediate pay-off is also too optimistic. The heart was dissected in 1540, the circulation of the blood was in 1670 or so, William Harvey; but the first heart transplant was in 1966. I'm not going to say it's going to take 400 years between the human genome sequence and the medical application of genetics, but it's going to take an awful lot longer than anybody had hoped. And I do feel that what biology needs to do now is to sit down and think.

JB: What's next in terms of your own scientific research?

JONES: To get back to being one of the great narrow minds of the century. One of the things on which Gould and I are in perfect harmony is that we are each among the six top experts in the world on the genetics of snails; and the other four agree. I have plans to go back to studying the population genetics of lan d ed snails in the Pyrenees; which is a lot more fun than writing books.