Evolutionary Synthesis: The Three Pioneers

One of the greatest scientific achievements of the last century was the integration of Darwin’s theory of evolution with Mendel’s theory of heredity to form what is known as the “Modern Synthesis” of evolutionary theory or “Evolutionary Synthesis” which is now the backbone of all biological thought.

Ernst Mayr, one of the principal architects of the Evolutionary Synthesis, wrote a superb retrospective on how this achievement came about in his “80 Years of Watching Evolutionary Scenery“–on his 100th birthday, few months before he died.

“Having reached the rare age of 100 years, I find myself in a unique position: I’m the last survivor of the golden age of the Evolutionary Synthesis. That status encourages me to present a personal account of what I experienced in the years (1920s to the 1950s) that were so crucial in the history of evolutionary biology.

“Evolutionary biology in its first 90 years (1859 to the 1940s) consisted of two widely divergent fields: evolutionary change in populations and biodiversity, the domains of geneticists and naturalists (systematicists), respectively…

“Fortunately, there was one evolutionist who had the background to be able to resolve the conflict between the geneticists and the naturalists. It was Theodosius Dobzhansky. He had grown up in Russia as a naturalist and beetle taxonomist, but, in 1927, he joined Morgan’s laboratory in America where he became thoroughly familiar with population genetics. He was ideally suited to show that the findings of the population geneticists and those of the European naturalists were fully compatible and that a synthesis of the theories of the two groups would provide a modern Darwinian paradigm, subsequently referred to as the ‘Evolutionary Synthesis.’ “

In Mayr’s account of the Evolutionary Synthesis, he acknowledges the critical role Theodosius Dobzhansky played in achieving the synthesis of genetics with the theory of evolution. Here is a detailed account of Dobzhansky’s achievementby one of his students.

“In 1972, Theodosius Dobzhansky addressed the convention of the National Association of Biology Teachers on the theme ‘Nothing in biology makes sense except in the light of evolution’… The place of biological evolution in human thought was, according to Dobzhansky, best expressed in a passage that he often quoted from Pierre Teilhard de Chardin: ‘Evolution is a general postulate to which all theories, all hypotheses, all systems must hence forward bow and which they must satisfy in order to be thinkable and true. Evolution is a light which illuminates all facts, a trajectory which all lines of thought must follow–this is what evolution is’.

“Dobzhansky’s ‘Genetics and the Origin of Species’ advanced a reasonably comprehensive account of the evolutionary process in genetic terms, laced with experimental evidence supporting the theoretical arguments. It had an enormous impact on naturalists and experimental biologists, who rapidly embraced the new understanding of the evolutionary process as one of genetic change in populations. Interest in evolutionary studies was greatly stimulated and contributions to the theory soon began to follow, extending the synthesis of genetics and natural selection to a variety of biological fields.”

By integrating the field of paleontology with natural selection and genetics, George G. Simpson played a vital role in building the Evolutionary Synthesis. Following is a classic paper by Simpson analyzing the geographical dispersal of various species over time.

“This I believe to be the type of pattern that would be shown by almost any form of life that had run its entire course from origin to extinction. A form appears in some center or ‘cradle,’ not an exact spot that could be marked with a monument but, say, a single biotic district or province. Thence it tends to spread steadily in all directions until it encounters insuperable barriers. After a time it begins to contract, possibly but not usually toward its center of origin and often splitting into disjunctive spots as it contracts. Finally it disappears.”

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4 Responses to Evolutionary Synthesis: The Three Pioneers

  1. Richard, thank you for recounting your encounter with academia; I have a very low opinion of universities and it keeps getting lower. Fortunately, this Internet age is the best of times for any independent scholar. Biology is one of the fields that is growing well, and I continue to benefit by studying it. One of my favorite biologist is George C Williams, who I just found out died recently. I plan to write about his books.

  2. Richard Bramwell says:

    You might find this interesting:
    Not aware of what I was getting into, I began a career in Wildlife Biology after completing a complex MSc. I did not want to repeat that, just to get the PhD diploma. After graduating, most work available to me was directly in government research, in quangos, or tedious ‘environmental assessment’ agencies. Still, the more I learned about science and biology the more enthralled I became. I had not ‘met’ Rand.

    Ten years later I dropped the whole career, though not the interest. Why, was rather extraordinary.

    The intellectual dishonesty among researchers & administrators gradually became apparent, and then abhorrent, to me. Aside from their bureaucratic & statist thinking, the Research Scientists themselves often disregarded
    - scientific method,
    - misrepresented statistical analyses, and conveniently
    - ignored (read: violated) one or another principle of the naturalist, genetic or molecular biology foundations of biology.
    - grossly embellished their government research proposals for funding, and
    - redirected obscene millions of taxpayers dollars to pet projects.

    At first, I thought I could survive by struggling to maintain my own integrity. One day, a ‘reprint’ appeared in my mailbox. It was an article by a scientist whose data I had analyzed, that was published in the international Journal of Wildlife Management.

    I remembered the results of his own analysis were middling, and possibly meaningful. He had come to me hoping that a more rigorous analysis would make matters more clear. I reorganized his data (no desktop computers then) and spent days calculating Multiple ANOVAs and Multiple Range tests. They demonstrated he had completely prohibitive under-sampling problems. There were no meaningful results. Full of appreciation, he holed up in his office for a month.

    Six months later, I was reading Atlas Shrugged and had a beginning grasp of Dr. Statler. Then that reprint arrived. I saw that he had used my work as Method, but had inserted his stats values as Results, for publication.

    Appalled, I went to the research scientist’s supervisor (later to become the Assistant to the Deputy Minister for Natural Resources of Ontario) to show what had been done. He shook his head, and said the unforgettable: “Richard, sometimes you have to decide if you want it right, or if you want a job.” My future was staring me in the face.

    A few days later, I reached the scene where John Galt chalks a correction into Daniel Quentin’s blackboard formulae for Galt’s motor. Along with all the other dishonesties, it was clear: end of career.

  3. Thanks Richard, for your comment, and thanks for your warning about Teilhard. As I see it, there have been two lines of biological thought in history: the naturalist line of which Darwin is the most illustrious example, which induces from a large base of diverse observations; and the molecular biology line which draws it’s inspiration from chemistry and uses microscopic observations and systematic experimentation, Watson and Crick being it’s most illustrious examples. The evolution synthesis systematically integrated these two strands of biological thought which had developed largely side by side.

  4. Richard Bramwell says:

    Two points:

    Molecular biology is the third synthesis, every bit as important as Mendelian genetics. One might argue they too related, but whereas the latter emerged from agriculture the former is from chemistry. If Earnst Mayr deserves recognition as a pioneer, then I would argue that Watson & Crick, despite their odd way of achieving it, are (or at least, represent a small group that serve as) the fourth, joint, pioneer. With the molecular code of DNA cracked the rush was on. Even the genome projects of today are spun from their solution of the DNA ‘puzzle’.

    The Pierre Teilhard de Chardin quotation used by Mayr, is very risky. Teilhard was more Neitzschean than Nietzsche, firmly believing that everything was ‘evolving’ to wards some bizarre and mystical Omega Point. He also advocated for the noosphere, the reification of thought/consciousness into a evanescent layer akin to the atmosphere. The noosphere contained the uploaded beliefs of humanity, which in turn literally influenced the beliefs of other humans. In some respects the Omega Point occurs when all ideas across all humanity become uniform, through that noosphere. This is ‘evolution’ to a Greater Consciousness (of course) and an ultra-synthetic version of the noosphere Very bizarre.

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