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Evolution quote: Sirks and Zirkle

At this point it might be well to insert a fact that has generally been overlooked by the historians of biology. The pre-evolutionary concept of species is generally given as a universally accepted view that species were constant and true breeding forms. Actually, the idea that species were completely stable and unalterable units had dominated biological thought for only about a hundred years when Darwin attacked and shattered it. All during classical and medieval times, species were looked upon as something specious. The species of an object were only its appearances and, proverbially, appearances were deceitful. Supposedly, species were only temporary forms and they could change into each other whenever the occasion demanded. Wheat could “degenerate” into barley, and barley into oats. Promiscuous and unsystematic hybridization supposedly could also produce new species. Both animals and plants had been described as changing their species whenever they were transported to new countries. But this widely accepted concept that species were only ephemeral and mutable units did not lead to a belief in evolution.

Before a belief in an orderly and systematic evolution could become respectable, the relative stability of species would have to be established. And, in the eighteenth century, as the result of careful and accurate research in the field of systematics, this view of species I did supersede the older one. But this careful research also showed that the stability of species was not absolute. There was evidence that some species had become altered, even if only a little bit. It was the secular accumulations of this residual instability in otherwise stabIe species that led to the theory of evolution.

From The Evolution of Biology (M J Sirks and Conway Zirkle, New York, Ronald Press, 1964: 305)

This is basically what I argue in my Species book. I am getting used to finding that the older and unappreciated historians did the same thing I did much later. They are generally very good historians.

Incidentally, I have been chided (chid?) by a recent reviewer for my use of Eric Nordenskiöld’s History of Biology, which was published in 1929. Why, I am unable to tell. Up until the period with which he is contemporary, he is a very good scholar, and his only sin with respect to the modern period is that he did not end up on the “right” side of history and gave credence to neo-Lamarckism. His scholarship, however, is impeccable, and he is a very useful source of citations that have been ignored or forgotten by the enlightened modern contextual historians who take Ernst Mayr seriously as a historian.

In general I find that the late nineteenth and early twentieth century historians of biology are more general, less Whiggish, and overall less likely to engage in simplistic dichotomies of internalistic issues. I was also chid (chided?) by that reviewer for doing an internalist history, even though I had given my apologia for doing so in the preface, and the reviewer gave no reason for thinking I should not have done one. Some fashions are ruling illusions, I guess. I even said that I hoped someone would do an externalist social history of “species”, but I guess that passage escaped the filter of the reviewer.

So I do not apologise for failing to follow fashions of either kind.


  1. Matthew Edney Matthew Edney

    Nice commentary — two comments (beyond commiserating about idiot reviewers, a cross we must all bear [and no doubt be! 🙂 ]):

    a) I’m having a fun time revisiting the later 19c/early 20c studies in my own field (map history); I find them generally much more competent than work from the mid-20c, which increasingly appear derivative.

    b) isn’t the preterite of “chide” … chud?


    • “Preterite”, huh. I always knew it as perfect tense… comes of learning grammar from a Latinist.

      • Preterite is actually another term for the simple past tense, not the perfect. Among those who advocate “preterite” rather than “past tense” are the authors of the Cambridge Grammar, who make the case that “past tense” is best used as a cover term for both the perfect and the simple past (which, in English, share certain properties in common). You’ll see it occasionally in Pullum’s LL posts.

        • This is where my total lack of grammar training shows itself. I picked it up by osmosis rather than instruction. But the aorist tense still gives me nightmares from Koine Greek…

  2. Back in grad school, I’d be at conferences with my adviser and we would go around the poster sessions. He would point out work that either duplicated or ignored research from more than a couple decades previous, and this happened a lot.

    Behe’s assurance on the stand in 2005 that his truncated version of lit search was perfectly adequate couldn’t be more mistaken.

    • That might be acceptable in science: after all, little science more than a decade is ever cited again. In history, though, the irony is laid on with a trowel.

  3. bob koepp bob koepp

    Actually, I think it’s probably not (or should not be) acceptable in science. Lack of knowledge of the history of one’s discipline means one is only half educated. Consider how much bunk has been published in prominent journals claiming that Crick’s Central Dogma has been “refuted.” Those making such claims often refer to Crick, not even realizing that the version of the CD they were taught is a bowdlerization due to Watson. Last time I checked, the original version of the CD (Crick’s version) has yet to be confronted with an actual counter example.

  4. Jeb Jeb

    Still remains one of the most important things Ive learnt , back when I was trying to make sense of the barnacle goose. Made a fundamental diffrence.


  5. Nietzsche wrote someplace that for the majority of the human race history begins with the grandparents. Since “time out of mind” is usually just a half a century, I take it as a good heuristic principle that any given intellectual revolt will turn out to be mounted against a scholarly consensus that is fairly recent. One also has to take into account the probability that the proponents of a new idea have invented a tale of ancient prejudice in order to make their efforts appear more heroic as in the sacred narratives of Galileo, Darwin, and Einstein.

  6. Jim Thomerson Jim Thomerson

    So long as Spontaneous Generation was widely accepted, evolution was a concept which would have been difficult to consider. Pasteur drove the final nail into SG and made the field wide open for evolutionary thinkers.

    Taxonomy is one area of biology where literature searches routinely goes back even as far as 1758, thanks to the law of priority. And one’s contributions stay in the literature for ever, if only in synonomies.

    • In fact I think that is wrong, Jim. Heterogenesis (spontaneous generation, or generatio aequivoca ) was a hot issue in the period from around 1700 to 1860, and what Pasteur did was take away one of the main planks of specific heterogenesis – that individual species generated from naught. Evolution, on the other hand, had been proposed since 1745. I have a history of ideas regarding spontaneous generation here and a history of ideas of evolution before Darwin here.

      My thought is that evolution became possible when, as the above quote implies, species became thought of as fixed, after 1686 and promoted by Linnaeus.

      On taxonomic citations, yes, they do go back to the tenth edition of Linnaeus’ Systema Naturae, but that is in itself a reason why those engaged in molecular systematics tend not to cite the traditional literature in favour of their own methods. In short, they are also blinded by the past.

  7. Jim Thomerson Jim Thomerson

    I commented on another forum that I liked to see a conventional expert on the group included among the authors of molecular systematic studies. Been there, done that, a couple of times and think (modestly, of course) that the studies are the better for my participation.

  8. Gerdien Gerdien

    Is Conway Zirkle the translator of Sirks’ book or is it a revised edition of an origial ‘De ontwikkeling van de biologie’ 1947?

    • The latter. Zirkle added prehistory, pre-Renaissance and updated it, with Sirks’ assistance. It’s a very good treatment, although I can’t speak to the Dutch original.

  9. wakuru wakuru

    thats my picture mr.john

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