STEPHEN JAY GOULD: THE PATTERN OF LIFE'S HISTORY

Comments by Stewart Kauffman, Marvin Minsky, Niles Eldredge, Murray Gell-Mann, Francisco Varela, J. Doyne Farmer, Steven Pinker, Nicholas Humphrey, Brian Goodwin, Steve Jones, George C. Williams, and Daniel C. Dennett

Steve Jones: Steve Gould is, to put it a bit too flippantly, a snail geneticist gone to the bad. All the worst storms happen in teacups, and the saucers of evolutionary biology have been well and truly filled with metaphorical tea as a result of his views on snails and other things.

Sometimes the message takes a bit of getting at, but it's always worth reading, even if I end up disagreeing with it. In some ways, there's too much baseball in his scientific papers — allegorical baseball, beautifully written speculations based on data which don't, to be brutally frank, support the speculation as well as they might. Ramblings like that fit perfectly well into a popular essay, though. I enjoy, very much, reading some of his evolutionary essays, some of which are masterpieces, there's just no question about it — genuine works of art in the scientific-literary form. But to use that approach in science itself is to be constantly in danger of a triumph of form over content.

Stuart Kauffman: Steve is extremely bright, inventive. He thoroughly understands paleontology; he thoroughly understands evolutionary biology. He has performed an enormous service in getting people to think about punctuated equilibrium, because you see the process of stasis/sudden change, which is a puzzle. It's the cessation of change for long periods of time. Since you always have mutations, why don't things continue changing? You either have to say that the particular form is highly adapted, optimal, and exists in a stable environment, or you have to be very puzzled. Steve has been enormously important in that sense.

Talking with Steve, or listening to him give a talk, is a bit like playing tennis with someone who's better than you are. It makes you play a better game than you can play. For years, Steve has wanted to find, in effect, what accounts for the order in biology, without having to appeal to selection to explain everything — that is, to the evolutionary "just-so stories." You can come up with some cockamamie account about why anything you look at was formed in evolution because it was useful for something. There is no way of checking such things. We're natural allies, because I'm trying to find sources of that natural order without appealing to selection, and yet we all know that selection is important.

Marvin Minsky: What I love about Stephen Gould is his ability both to research and to explain the possible evolutionary pathways that might have led to what we see in particular cases. His explanations and hypotheses are constructed from the most diverse kinds of evidence, by combining both general principles and particular details from many different fields. It's a wonder to see so many aspects synthesized at all — and perhaps more of a wonder to see them described with such beauty and clarity.

Niles Eldredge: Steve and I are like brothers, and when we get together we mostly like to talk about the things we disagree on, but of course the rest of the world is hard pressed to see how we differ on anything at all. Yet we do. That, to us, is the most interesting stuff. When we first wrote the punctuated-equilibrium papers, I thought it was more about mode and Steve thought it was more about tempo, using the two phrases from George G. Simpson's Tempo and Mode in Evolution. We had a different take on what it all meant. I think to some degree we probably still do.

Steve is prodigious. I never met somebody who was so smart who worked so hard. He is a marvelous scholar. I have never found anybody who could grasp the essence of an issue so quickly, either. He was an inspiration to me when we were graduate students, because he showed that it was possible — and, indeed, it was almost an obligation — for young people to think critically, to think theoretically, and to publish. He showed the way.

The downside of being associated with Steve, of course, is that sometimes you feel like you are standing in a shadow, that you're one of the also-rans. But I've benefited far more than I've suffered from being associated with Steve, and I think we're closer now than perhaps ever before.

Murray Gell-Mann: Stephen Jay Gould and I collaborated in consulting on, and obtaining signatures for, an amicus-curiae brief for the Supreme Court in Edwards v. Aguillard, which was the Louisiana creationism case. We called on the Supreme Court to declare that it was unconstitutional to force science teachers in Louisiana to devote equal time to the doctrine of creationism if and when they taught about evolution, since evolution is the scientific account of how life developed on earth and creationism is an idea that no one would believe today who is not starting from some form of fundamentalist religious dogmatism. Our side won, seven to two.

Francisco Varela: I feel very close to many of the fundamental ideas that Steve Gould has come up with, and I've learned from his critique of the adaptationist program, in the famous paper he wrote with Lewontin.

I've been fighting for many years, in the case of the operation of the brain, to make the point that the brain is not an information machine that picks up information and creates an optimal representation of what's out there. The whole story is quite otherwise. There is an absolutely identical analogy with evolution. In the traditional, simplistic Darwinian view, adaptation is some form of optimal fit with a given world. What Gould is saying is that the adaptationist idea that there's an ideal world to which species fit is just nonsense; that there is instead an intrinsic story, an internal story, to evolution — or intrinsic factors, as they are called now — which shapes the niche, and the form of the species, just as much. This is the same thing I'm saying about the brain — or about the immune system, for that matter. His critique of the post-Darwinian adaptationist view is very much in resonance with my own work.

That's saying nothing about something else I admire enormously: Gould's ability to communicate ideas to the large public. That's his unique genius. Anybody who has read, for example, Wonderful Life, realizes that he can take something which is obscure and abstruse, and not only make it relevant to the large public, but actually in the same stroke produce a new reading of a fundamental chapter of biology.

With regard to the Dawkins-Gould debate, if I wanted to be brutal I would say that Gould is right and Dawkins is wrong.

J. Doyne Farmer: Stephen Jay Gould is an excellent writer and a clear thinker, and he has a real gift for writing about scientific issues and providing enough personality and drama so that nonscientists can get excited about what he's saying: he's perhaps the Herbert Spencer of our day. He doesn't know complexity theory and he doesn't care. My guess is that he wouldn't see much value in something like artificial life.

Gould is from the old school. He's a biologist, he's not educated mathematically. He may have a perfectly clear concept of what physics is, but he certainly isn't in any sense attempting to achieve the levels of abstraction or generality for evolution or evolutionary biology that have been achieved in physics.

Steven Pinker: In Ernst Mayr's authoritative history of biological thought, he notes the irony that paleontologists were the biologists most skeptical of natural selection. Presumably it's because paleontologists study organisms after they've turned into rocks, and their first concern can't be how stomachs work, or how eyes work, or how the visual circuitry of the brain works. The evolutionary geneticist John Maynard Smith has suggested that Gould fits into this tradition in much of his writing, because natural selection doesn't answer the first questions that paleontologists face — namely, what are the grand patterns in the history of life: why does one kind of animal replace another over a span of tens of millions of years?

To be fair, there used to be a widespread idea that natural selection could explain just such facts. The mammals succeeded the reptiles because in some way they were better adapted, or fitter. Gould has eloquently shown some of the problems of this application. But it's something that modern Darwinians, like Maynard Smith, Richard Dawkins, and George Williams, wouldn't claim to begin with. They'd be happy to concede that many macroevolutionary phenomena can't be explained by natural selection — a clear example being the possible extinction of the dinosaurs because of a collision between the earth and an asteroid or a comet. But biologists outside of paleontology study the complex functioning of individual organisms, and that's why they're much more likely to appreciate the power of natural selection.

Many scientific debates are like the blind men and the elephant: different people are interested in different aspects of the problem. Scientists will imagine that they're in sharp disagreement with other scientists, when they're merely studying something else. Gould's criticisms of Dawkins, Helena Cronin, and those he calls sociobiologists are a bit like that: those people are using natural selection to answer questions about complex form and behavior, where natural selection is required, and he points to areas of biology like mass extinctions or differences in banding patterns on snails, where it's not required. In fact, Dawkins would be the first to agree that there are certain things for which natural selection is not the best explanation. What Dawkins says — quite convincingly, in my mind — is that the kinds of questions that a physiologist or an anatomist or an ethologist or a cognitive scientist is interested in are the kinds of questions that you do need natural selection for.

I greatly admire Steve Gould's writings, and I've learned an enormous amount of biology from them. And I agree with some of his leitmotifs, such as the lack of progress in evolution, the importance of understanding phylogeny as a tree rather than as a ladder, and the importance of contingent historical events in evolution. But there are others that I have problems with. For one thing, I don't think he fully acknowledges the complexity of everyday unconscious mental processes. He has drawn misleading analogies about how the mind might be like a computer or a general-purpose learning device. He suggests that just as a computer can play tic-tac-toe as well as calculate a company's payroll, the brain could have been designed for one thing and used for other things. But that's not quite right. You can't take a computer out of the box and have it both compute a company's payroll and play tic-tac-toe. Someone has to have programmed it specifically for both tasks, so the analogy falls apart, even in the case of the computer. It falls apart even more dramatically in the case of the brain. To get the brain to do all the different intelligent things that it does, there has to have been nature's equivalent of engineering. You don't just throw a few billion neurons together and have it do incredible feats like stringing words into meaningful sentences and recognizing faces and calculating the trajectories of moving objects.

We're apt to think there isn't much to pedestrian psychological processes, because they work so well. Just as we're apt to underestimate how complex digestion is until we study the biochemistry of digestion, we're apt to underestimate how complex the mind is from our perspective as commonsense thinkers — exactly because it's designed to work without our conscious awareness. I sometimes think that Gould, as someone who has never been faced with explaining ordinary perception and behavior in his day-to- day work, is apt to underestimate it and therefore to give short shrift to natural selection, which is the only force capable of explaining that kind of complexity.

Nicholas Humphrey: Some of what Richard Dawkins and Steve Gould go on about in their debate is old-hat, and they ought to stop it. New things have come up since The Selfish Gene and since Gould's earlier writing. We're into new territory now. The evolution of evolvability is a question of whether there can be selection for the ability to evolve in changed circumstances. There's increasing evidence that there are ways in which biological systems can be more or less adapted to evolve.

Sex is one very simple example. Sexually reproducing organisms are much better at evolving. There are a lot of other much more interesting levels, much more interesting mechanisms at the biochemical level, where you can get particular sorts of DNA that are better at evolving than others. A lot of the dispute between Gould and Dawkins could be resolved by these new ideas.

Brian Goodwin: Stephen Jay Gould — now, there's a name to conjure with, eh? Stephen has an orientation that I find paradoxical, because the bottom line is that he's a Darwinist. He believes that natural selection is the final arbiter, the final cause in evolution. But for me, natural selection explains very little. Stephen is well aware of this. He talks about morphospace, he agrees that we have to understand morphospace. For me, this is where explanations of form and taxonomy are to be found, and natural selection explains very little.

I have immense respect for Stephen and the range and quality of his ideas, but where we part company is on the matter of emphasis. Stephen believes that biology is a historical science, and natural selection is the final arbiter of what survives and what does not. But that's not the interesting question, which is, What emerges? He's well aware of that. I think he regards me as pushing too much on the problems of emergence and morphology and morphogenesis.