Thursday, November 8, 2018

REWRITING HISTORY TO SUSTAIN A MYTH


In my last post (in Sept, as I did not post in October), I briefly mentioned a new book by David Quammen, The Tangled Tree: A Radical New History of Life. Its focus is on later developments in the science of evolution, but it does pay some attention to Darwin. Now that I have had a chance to read at least these and related parts of the book, I can say once again that the myths about Darwin continue. For a science that is supposed to offer insights into the origins of life forms, evolutionary theory is preciously ignorant of its own origins.

Quammen treats evolution as if it were Darwin’s own theory. In discussing Darwin’s early Notebooks (before he came up with natural selection), Quammen refers to evolution as “his theory.” Like every other writer, he presents Darwin as if he had a blank mind when he went on his Beagle voyage, as if he came up with evolution all on his own. Yes, Quammen acknowledges that Darwin had predecessors, including his own grandfather, Erasmus, but he regards them as figures who may be dismissed, not having accomplished too much except for their wild speculations about evolution. He gives them all short shrift, leaving us with no details of what they actually did accomplish. They did more than engage in wild speculation.

Quammen faults Erasmus Darwin for having “offered no material mechanism” for his evolutionary ideas, but that is not what the earlier Darwin should be remembered for. Erasmus Darwin admitted he did not know the cause of evolutionary change, but he could still see it happening. What Darwin grand-père did was to present enough evidence for a general theory of evolution to make it a reasonable hypothesis to pursue. The scandal of science was that other scientists would not acknowledge what a good job he did at this, his grandson Charles never admitted it, and historians of science today are still loathe to deal with it.

Towards Charles Darwin, Quammen is extremely generous. Even though Darwin got a lot wrong, it is not his fault, as he did not have the advanced knowledge from later genetics, molecular biology, and more. He did not even know how heredity works. Referring to Charles, Quammen says, “He did the best he could, which was exceedingly well, with the evidence he could see.” But this is even more true of Erasmus who had less information to work with than his grandson did. In Erasmus’s day, it was not even settled whether extinction was a fact of life and the age of the earth was still hotly debated. Yet Erasmus could see enough evidence to make evolution a credible hypothesis. Quammen doesn’t get Erasmus’s accomplishment at all.

The biggest shock of Quammen’s book is that he completely omits Robert Chambers whose book Vestiges of the Natural History of Creation, published 15 years before Charles Darwin’s Origin of Species, really put evolutionary theory on the map. Chambers did this by proving that evolution was more probable than the idea of special creation. He assembled almost all the same evidence that Darwin was privately working on without publishing his conclusions. (Darwin wrote two preliminary unpublished essays in 1842 and 1844; the second one was completed in May, several months before Chambers anonymously published Vestiges in October.)

Chambers saw what Darwin saw: A large pattern of evidence made evolution the better explanation for what was going on. Here is just some of the evidence Chambers presented: the fossil record, incomplete as it was, supported the idea that life forms were evolving and, just by the way, man was a late arrival (which did not make mainstream scientists happy); the commonality of structure in various organic beings (Chambers gave an example, also used later by Darwin, of the bone structure in a human hand being similar to that in a bat’s wing); the existence of intermediate forms and gradations, which Chambers often called links (though he became infamous for suggesting that spontaneous combustion played a role, he loved to emphasize how gradual evolution was); the fact that nature’s potential for variation could be seen in artificial selection or breeding; and the startling resemblance of the embryos of many different adult animals, as if they all had the same common ancestor.

Small wonder then that so many young scientists were favorably inclined towards the development hypothesis, as it was known, as a result of Vestiges; ten editions had come out before Origin appeared. Quammen falsely claims that Darwin’s book all on its own “converted a generation of scientists to the idea of evolution.” The conversion process had actually begun earlier with Chambers’s book. Quammen fails to give credit where it is due and bestows credit where it is exaggerated.

Chambers is still overlooked by most writers, and Quammen joins this grand tradition of erasing a Darwin competitor from history. Vestiges came out in 1844 and, by 1847, most scientists, including Darwin, had figured out Chambers was the author. He was working class and that could not be tolerated in science which was dominated by the upper classes. He was also holistic in his approach to evolution, which meant that he did not see mankind as the be-all and end-all of nature. That human beings are part of a whole and are related to other parts of the whole should make us more humble. That is not a lesson western scientists wanted to learn.

Chambers offered a far more humane version of evolution than Darwin who was obsessed with ranking organisms (“groups subordinate to groups” appears throughout Origin) and with upholding the idea that the dominant species become ever more dominant. Western scientists tend to study nature to learn how to become more dominant and controlling. That was not Chambers’s goal, except that he was after any information that could improve the well-being of the lower classes.

There is a reason why people like Chambers are erased from history and it does not speak well for the inhumanity that constantly recurs in science.

The rest of Quammen’s book is quite fascinating. He has a great story to tell about new discoveries in molecular biology, horizontal gene transfers, and evolution among bacteria proceeding by absorption and not by natural selection. He would replace Darwin’s tree metaphor with the idea of a web. And then another curious omission on his part. Quammen never tells his readers that Erasmus Darwin chose the web as the best way to describe what happens in nature. “Life’s subtle woof in Nature’s loom is wove,” he wrote. And not just one web, but many webs: “webs with webs unite” and “the living web expands.” In this sense, Erasmus saw further ahead than Charles and he did it with much less evidence.

© 2018 Leon Zitzer


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