The evitability of man
Tony Osman
BULLY FOR BRONTOSAURUS by Stephen Jay Gould Hutchinson Radius, £16.99, pp. 540 You can think of this collection of essays — articles reprinted from the magazine Natural History — as a series of conversations with Gould. This is a privilege. He is a distinguished scientist he was the joint author of a theory that showed how evolution must have occurred; but more to the point for these essays conversations — he combines this with a broad education outside his own specialty. Gould sings in a choir, knows who Kropotkin was (a turn-of-the-century theorist of anarchism), and recognises that a QWERTY keyboard on a computer and appendicitis in humans are both evidence for, admittedly different, kinds of evolu- tion. As well as talking to us about some of the queries we have concerning his speciali- ty, he shows us what is special about the way that a scientist — a numerate scientist — looks at the world around him.
The most moving example of this is the way he thought about his own cancer. He tells us, in one of these essays, how he was diagnosed as suffering from mesothelioma. His doctor told him that there was not much in the medical literature about this cancer. She meant to be humane, but was ill-advised. As he says,
trying to keep an intellectual away from literature works about as well as recommend- ing chastity to homo sapiens.
In no time at all, Gould had extracted a collection of references from Harvard's beautifully automated library index system.
What he found out was that, for this can- cer, the 'median life expectancy after dis- covery was eight months'. No matter how you look at it, this was serious news. But Gould understood statistics. The fact that eight months was a median expectancy did not mean that he had eight months to live. There would be some who died quickly and others who lived longer, which would make the statistics come out right. Gould resolved to be in this second group. He talked to people who helped to define what kind of personality held out against cancer, and recognised that his was similar though perhaps in need of reinforcement. He is still around. Not many people have used an understanding of statistics to extend their own lives.
Gould is, of course, marvellous in his own field — evolution. His previous, and justifiably best-selling book, Wonderful Life, walked us through the geological evidence — the Burgess Shale in Toronto — that demonstrated clearly that there was no certainty that humans would evolve. Those rocks contain the traces of an almost com- pletely fresh start, very early in the Earth's life, after a global calamity. It so happened that one of the evolutionary chains that started then was one that could lead to humans: others simply could not. Because we humans write the books about evolution, we tend to claim that we are Nature's triumph: that was certainly an unrecognised axiom in the Victorian period, when Darwinism was enunciated. But as essays in this book continually remind us, the evolution of mankind was contingent, not guaranteed. And we are not particularly the 'triumph of evolution'. Were they selfconscious, any of the creatures now alive could claim to be triumphs of evolution — they are the successful results of evolution to date. Of course, the fact that they cannot actually claim anything is what makes man unique. Gould repeatedly points out that mankind is the only selfconscious 'group', the only one capable of reflection. Were it not for some chance survivals in the period immor- talised in the Burgess Shales, there would have been no creatures that could produce theories, let alone write about them.
Mankind certainly did evolve from sim- pler creatures. There is no doubt that mankind, and the other forms of life around us, arose by evolution. Because he feels strongly about education, Gould spends some time on a contemptuous demolition of American textbooks that try to sit on the fence between 'creationism', which holds that the human race had no antecedents, and evolution. But for most of us, he is more fascinating when answering the kind of questions that are asked by those of us who do not have his intimate knowledge of what Darwinism really says.
Quite a few of these essays are triggered by letters from people who are baffled by some element of what they understand by Darwinism. If Darwinism is, for example, about the extinction of inefficient features, then why do men have totally non- functional nipples? (Answer: It is to do with development from the fertilised egg, which is bisexual. The characteristics of one or other sex are made more emphatic later.) Again, if Darwin describes Nature as 'red in tooth and claw' (he didn't, but his followers did), does this justify ruthless selfishness? (Answer: No it doesn't, and this is where the reference to Kropotkin comes M. He wrote a book with the title Mutual Aid.) Gould even tells us about a rather more technical question that must have occurred to many of us, which concerns major devel- opments, such as wings. It is not really imaginable that wings developed instanta- neously, between one generation and the next, and in any case Darwinism is not about 'instantaneous evolution'. But if the development started as only a modest change, what advantage could the change have given? Biologists nowadays believe that birds evolved from one of the small dinosaurs: what value could undeveloped proto-wings have had for these reptiles? Gould's answer is that the proto-wings probably helped in temperature control: when they had developed far enough, they had greater value for movement. This is an exhilarating, absorbing and broad-ranging book — but Gould is most fascinating when he talks about his own subject — evolution. Always he reminds us that although we can look backwards and see how the world around us has evolved, this does not mean that if we ran the clock backwards and re-started, the world would eventually be as it is now. We have already seen that the Burgess Shales record a for- tuitous start to the chain that led to mankind. Another piece of evidence con- cerns a later time.
Mammals, our ancestors, were around at the time of the dinosaurs. But they were tiny, and with no apparent great future: it was the dinosaurs that were dominant. But for a cosmic cataclysm that destroyed the dinosaurs, mammals would probably have stayed small and insignificant. There would never have been humans, there would never have been thought, there would never have been language.
'It's that Friday feeling.'
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