Charles Darwin’s theory of evolution through natural selection, published in On the Origin of Species in 1859, is one of the great intellectual achievements of western civilization. The ideas on which it was based—the natural development of today’s organisms from forms far more primitive, perhaps ultimately from inorganic materials—had been around from the 18th century, and indeed one finds hints back in the days of the ancient Greeks. But it was Darwin who firmly established that Genesis was wrong: we are not the miraculous creation of a good God all within a week, and that our ancestors were monkeys—not, one hastens to say, monkeys of a kind extant today, but certainly more primitive primates. It was also Darwin who supplied the mechanism we hold primary today: a struggle for existence (more precisely a struggle for reproduction) leading to a natural winnowing of organisms, with some (the fitter) succeeding and some (the less fit) failing. All of this given enough time and an ongoing supply of variation leads to change, through a process akin to the selective breeding practiced by agriculturalists and hobby breeders—plants and animals of all kinds, produced by means akin to the turnips and clover, the bulldogs and budgerigars of the human selector.
R. Paul Thompson’s A Remarkable Journey: The Story of Evolution is a very useful, relatively short, nicely written and extremely well-illustrated book that covers much of this story in a way that deserves a wide readership. Thompson starts his tale with Darwin and the discovery of his theory. We follow the young man, a sometime medical student and then a would-be Anglican parson, as he sets out on a five-year voyage of discovery around South America on HMS Beagle. We share with him the exciting flora and fauna of the Galapagos, the archipelago of islands in the Pacific that the Beagle visited on its long way home. Then comes the theorizing, the writing and the publishing of the Origin, and a few years later, the Descent of Man devoted to our own species, humankind. Darwin had always included us in the story, but in the Origin was concerned first to get the basics of his thinking out on display.
Troubling for Darwin but fascinating for us is the fact that, for all of his great advances, he had only part of the story. He did not have an adequate theory of heredity, what we call genetics. Unknown to him—unknown to practically everybody of his day—across Europe in a Moravian monastery the future abbot, Gregor Mendel, was doing massive studies of the transmission of characters in peas—wrinkled, smooth; yellow, green; tall, short—and uncovering the laws that govern transmission. Unfortunately these ideas sat unappreciated until the beginning of the 20th century, when a number of people simultaneously moved forward on heredity and found that Mendel had anticipated them. By then he was dead, unaware that he was going to be perceived as one of the giants of 19th-century science.
As we move into the 20th century, Thompson—who has a knack for sprightly narrative as well as a nice nose for biographical detail—picks up the pace. We learn about the troubles when folks could not decide whether Darwinian selection or Mendelian genetics was more important, and how this was not resolved until the 1930s when the mathematical biologists—notably Ronald Fisher and J.B.S. Haldane in Britain and Sewall Wright in America—showed the way to bring the two threads together. We then move on to the empiricists such as the fruitfly geneticist Theodosius Dobzhansky and the early expert on the diversification of living forms, Ernst Mayr, taking over and as it were putting flesh on the mathematical skeleton. A skilled mathematician himself, Thompson is very good on the coming of molecular biology and how this had its role to play.
Then we move into the present era. Thompson talks not only of the science but also of the controversies that came in its wake. Notable were the attacks by those whose deep-seated Marxist inclinations were equalled only by their impressive biological credentials. They attacked ferociously what they saw as illicit value assumptions being smuggled into evolutionary biology. Even to this day there is rancour about the attacks on Edward O. Wilson, the author of the magisterial volume on the evolution of social behaviour—Sociobiology: The New Synthesis. What made the onslaught particularly painful was that two of the most prominent critics, population geneticist Richard Lewontin and paleontologist Stephen Jay Gould, were in the same Harvard department as their victim, Wilson.
Penultimately, Thompson looks at work on development, that is embryology. Properly he sees this as an addition, or fleshing out, of Darwin’s work, rather than something challenging it. Any talk of new paradigms is just silly, he suggests. Finally, Thompson has a few things to say about the clash between science and religion, and he points out the idiosyncratic nature of evangelical literalist theology. He rightly has little time for those who see religion trumping science and not a lot more time for those who see science trumping religion. One does not have to be religious to be an evolutionist, but neither does one have to be a non-believer.
It is no criticism of A Remarkable Journey to say that this is a book clearly written by a philosopher with an interest in history and biology rather than a book written by a historian with an interest in philosophy. The treatment of Darwin’s theory in the Origin brings this to the fore. Thompson is very good at picking apart the details, showing how they are all connected, and then putting them back together again. There are some really helpful diagrams laying out the structure and showing with care how truly Darwin spoke when he said that his theory was “one long argument.” But by going at things this way, there are other things downplayed or missed that someone from the historical side of things might pick up and emphasize. For instance, one might note how deeply Darwin’s thinking in the Origin is immersed in the natural theology of his day. It is true that Darwin does not want the involvement of an intervening God ready to do miracles. But he clearly thinks that God is right behind everything, and says so:
Authors of the highest eminence seem to be fully satisfied with the view that each species has been independently created. To my mind it accords better with what we know of the laws impressed on matter by the Creator, that the production and extinction of the past and present inhabitants of the world should have been due to secondary causes, like those determining the birth and death of the individual. When I view all beings not as special creations, but as the lineal descendants of some few beings which lived long before the first bed of the Silurian system was deposited, they seem to me to become ennobled.
When you stop to consider it, this is a remarkable thing for someone to say, especially in a book supposedly on science. “Accords better” with what we know of the actions of “the Creator”; “all beings” become “ennobled”; and so forth. One absolutely cannot imagine any of today’s leading evolutionists using this kind of language, even in the faculty club at the end of a long day in the laboratory. If one of their graduate students were to use such language, the red pen would come out and it might be suggested that he or she were better suited for a life in the pulpit than in the science departments of universities. But Darwin uses it. One suspects that just as his science was incomplete, judged by today’s standards, it would be thought that his philosophy of science—what one can and what one cannot put in science—is incomplete. It is not so much that Darwin is wrong but that there is something very old-fashioned about the very fabric of his thinking, given the way that he mixes up science and religion as he does.
One thing that did strike me forcibly about Thompson’s book is that it is dynamic in an altogether admirable way. Within living memory, when people turned to science there was somewhat of a tendency to think statically, taking cross sections of science frozen in time. I can remember when I studied philosophy of science at McMaster University in the 1960s, the (admirable) text that we used took contemporary science—mainly physics I should add—and asked us to consider how it works today. So, for instance, we talked about what people across the campus right then thought about mass and length and acceleration and so forth.
We did not dig very far back in time. But now—thanks in large part to Thomas Kuhn’s Structure of Scientific Revolutions—those of us with philosophical interests turn happily to science as it has evolved through several eras. And this is the very strong backbone to Thompson’s book. He shows us evolutionary science as it moves forward through time, from Darwin’s first epoch-defining contributions, as it is enhanced and developed, as threads come together, as it deals with the massive influx from other areas of science—one thinks particularly of molecular biology—and as it comes down to the present. The disputes, unpleasant though they were at the time, also have a place in the story. There is something of an image of science—certainly an image that science would like to have—of cool rational people, in white lab coats, putting aside the world as they peer into the mysteries of nature, rationally and in sensible order. There is a reason why the late Karl Popper was such a favourite of scientists. He told them that (to use the language of Thomas Henry Huxley) they must sit down before the facts as a little child, and if the facts go against their beliefs—no matter how cherished—they must abandon the beliefs. They have been “falsified.” Scientists thus are people of disinterested integrity. Why then do scientists fall out? And why is it often the very best scientists who fall out? A great strength of A Remarkable Journey is that it gives us insights into the way that science is not quite the objective phenomenon that the Popperians would have it be. Science can reflect interests and values just like the rest of human culture—and, just like the rest of culture, scientists can fall out over these interests and values.
Of course, it is not really surprising that evolution should be so controversial. As Thompson’s last chapter reminds us, evolution is not just one theory among equals. By and large, people do not get too heated about the composition of sulphuric acid. There are two hydrogen atoms, to one sulphur atom, to four oxygen atoms. That’s it. But evolution is another matter. It strikes right at the heart of virtually all religions—in fact, I would say more so than Thompson lets on, although he certainly hints at some of the reasons why evolutionary theory is not only magnificent but in many respects deeply worrying.
The book ends with a useful glossary and timeline. It also has some rather heavy mathematical appendices. Frankly, I am not quite sure about these. They may be too technical for the general reader and not sufficiently detailed for the expert. But A Remarkable Journey: The Story of Evolution is a very polished piece of work—a terrific gift to give to an undergraduate or even a high school student. The recipient might be so excited that he or she ends up spending a whole life studying evolution. What better praise can a professor who writes a book have than that?