Ernst Mayr Recounts 20th Century Evolution Battles
apostle of Darwinian evolution, Ernst Mayr, turned 100 recently. His mind still sharp, he recounted in the July 2 issue of Science1 the battles that led to “Neo-Darwinism” in the 1940s. Surprising though it may be to some, there was no consensus on speciation, natural selection and other key evolutionary concepts for eighty years since Darwin published his book. Only in the 1940s did a compromise called the Neo-Darwinian Synthesis satisfy the majority of Darwinians. Neo-Darwinism still reigns today, despite strong minority positions such as punctuated equilibria and Gaia, along with a number of sects that deny certain aspects of the Synthesis.
Mayr lays the background of his youthful acceptance of evolution:
Curiously, I cannot pinpoint the age at which I became an evolutionist. I received all of my education in Germany, where evolution was not really controversial. In the gymnasium (equivalent to a U.S. high school), my biology teacher took evolution for granted. So, I am quite certain, did my parents–who, to interest their three teenage sons, subscribed to a popular natural history journal that accepted evolution as a fact. Indeed, in Germany at that time there was no Protestant fundamentalism. And after I had entered university, no one raised any questions about evolution, either in my medical curriculum or in my preparations for the Ph.D. Those who were unable to adopt creation as a plausible solution for biological diversity concluded that evolution was the only rational explanation for the living world.
Nevertheless, he continues, “Even though creationism was not a major issue, evolutionary biology was nonetheless badly split by controversies,” namely, “the causation of evolutionary change and the validity of various theories of evolution.” These seem pretty all-encompassing. He describes some of the early battles:
- Philosophy of science: “… the philosophy of science at that time was totally dominated by physics and by typology (essentialism). This philosophy was appropriate for the physical sciences but entirely unsuitable as a foundation for theories dealing with biological populations….”
- Sub-issues: “…the paradigm of Darwinian evolution was not a single theory, as Darwin always insisted, but was actually composed of five quite independent theories. Two of these were readily accepted by the Darwinians: the simple fact of evolution (the ‘non-constancy of species’ as Darwin called it) and the branching theory of common descent. The other three–gradual evolution, the multiplication of species, and natural selection–were accepted by only a minority of Darwin’s followers. Indeed, these three theories were not universally accepted until the so-called Evolutionary Synthesis of the 1940s.”
- International rivalry: “Superimposed on these conceptual differences were others that arose because of the preferences of evolutionists in different countries. The evolutionary theories considered valid in England or in France were rejected in Germany or the United States. One powerful author in a particular country often could determine the thinking of all his fellow scientists.”
- Interdisciplinary rivalry: “Finally, different evolutionary theories were often favored by scholars in different branches of biology–say, genetics, or developmental biology, or natural history.”
- Gradual vs. jerky change: “We naturalists thought that evolution was indeed a gradual process, as Darwin had always insisted. Our material provided hundreds of illustrations of widespread species that gradually changed throughout their geographic range. By contrast, most early Mendelians, impressed by the discontinuous nature of genetic changes (‘mutations’), thought that these mutations provided evidence for a saltational origin of new species.”
- Biodiversity: The founders of population genetics accepted natural selection, but “Several historians have mistakenly thought that this synthesis within genetics had solved all the problems of Darwinism. That assumption, however, failed to take account of an important gap. One of the two major branches of evolutionary biology, the study of the origin of biodiversity, had been left out of the major treatises of Fisher, Haldane, and Wright.” Mayr claims that this problem had been solved by European taxonomists.
- Paradox and schism: “Thus, evolutionary biology around 1930 found itself in a curious position. It faced two major seemingly unsolved problems: the adaptive changes of populations and the origin of biodiversity.” For instance, “As a student in Germany in the 1920s, I belonged to a German school of evolutionary taxonomists that was unrepresented in the United States. Our tradition placed great stress on geographic variation within species, and particularly on the importance of geographic isolation and its role in leading to the origin of new species. It accepted a Lamarckian inheritance of newly acquired characters but simultaneously accepted natural selection as facilitating gradual evolution. We decisively rejected any saltational origin of new species, as had been postulated by DeVries.”
- Object of selection: “The two belief systems had only one inconsistency—the object of natural selection. For the geneticists the object of selection had been the gene since the 1920s, but for most naturalists it was the individual. Elliot Sober showed how one could resolve this conflict. He pointed out that one must discriminate between selection of an object and selection for an object.”
Mayr claims that the taxonomists and the population geneticists had solved parts of the problem; all that remained was to get the parties together. That compromise was achieved by Theodosius Dobzhansky with Mayr’s assistance. He claims the neo-Darwinian synthesis that resulted has been remarkably stable, even through the discovery of DNA and the revolution in molecular genetics, but part of that stability has been due to enforcement: “At a meeting in Princeton in 1947, the new paradigm was fully acknowledged and it was confirmed again and again in the next 60 years. Whenever an author claimed to have found an error in the Synthesis, his claim was rapidly refuted.”
In his conclusion, Mayr notes that new battles have arisen over allopatric vs. sympatric speciation, the enormous amount of biodiversity, and non-allopatric genetic mechanisms such as “speciation by hybridization, by polyploidy and other chromosome rearrangements, by lateral gene transfer, and by symbiogenesis.” He regrets he will not be able to continue exploring the new frontiers of evolutionary biology.
1Ernst Mayr, “80 Years of Watching the Evolutionary Scenery,” Science, Vol 305, Issue 5680, 46-47, 2 July 2004, [DOI: 10.1126/science.1100561].
Did you know that believers in natural selection were in the minority in the 1920s, and that many evolutionists believed in rapid, saltational change instead of gradualism? You heard one of the living legends of Darwinism, Ernst Mayr, say it himself. Notice how nothing has changed. Early 20th century evolutionists disagreed on the mechanism of evolution (natural selection, Lamarckism or other) on the pace of evolution (gradual vs. saltational), and on mechanism of speciation. Those seem like pretty major issues. How can Darwin’s hunch rise above the status of hypothesis without answers to these questions? The only things they agreed on were: (1) evolution is a fact, and (2) things change. The same controversies go on today. Evolutionists fight over how species split into two, how fast things happen, and the role of natural selection, and other major issues, but they still dogmatically claim that (1) evolution is a fact, and (2) things change. The first is belief, not science, and the second is too vague to be called science; even creationists acknowledge that things change. It does not follow that humans had bacteria ancestors.
Mayr’s account sounds less like a scientific law emerging from the evidence, and more like a victory of two major factions of storytellers over rivals, until they agreed to give a little and meet in the middle (thesis vs. antithesis -> Synthesis). The antagonists came to a compromise, and hashed out new talking points for the students: “Father Charlie was right about gradualism and natural selection, but Mendel has helped forge an even better story: mutations provide the raw material for variation, then natural selection preserves the fittest. We will call this neo-Darwinism.” Students, attracted to anything that is Neo, thought this was cool. The official sound bite for reporters became, “We may have some disagreements about the mechanism of evolution, but all scientists agree evolution is a fact.” These short, glittering mythoids sufficed to keep most peasants compliant.
Those interested in the relation of Mendel to Darwin will find this paragraph interesting:
When Mendel’s laws were rediscovered in 1900, there was widespread hope that they would lead to a unification of the conflicting theories on speciation. Unfortunately, it turned out that the three geneticists most interested in evolution–Bateson, DeVries, and Johannsen–were typologists and opted for a mutational origin (by saltation) of new species. Worse, they rejected gradual evolution through the natural selection of small variants. For their part, the naturalists erroneously thought that the geneticists had achieved a consensus based on saltational speciation, and this led to a long-lasting controversy between the naturalists and the early Mendelians.
Long-lasting, all right; it was about 47 years after this “rediscovery” of a 33-year old paper (70 years total) before the Darwinians found a way to incorporate Mendel’s inconvenient laws of discrete inheritance into their story.
Textbooks present Darwin as if his ideas were so intuitively obvious that late 19th century scientists instantly saw the light and embraced it, and lived happily ever after. As we know from frequent reports on Darwinism and Evolutionary Theory in these pages, controversies still rage about the mechanisms of evolution, the pace of evolution, the mechanism of speciation and the origin of complex structures. Nothing has advanced except the power of the Darwin Party to enforce their views.
How tragic to hear that the Reformation was dead in Germany by the time Mayr went to school. The country where Martin Luther had taken his brave stand on the Word of God had cast off its heritage for a radical revolutionary, Ernst Haeckel, who replaced it with the Word of Charlie. The early Protestant reformers had the will to withstand the Catholic counter-reformation, but their heirs, asleep at the switch, let the Darwinian revolution take over with hardly a word of protest. So now the revolution has become the mainstream, controlling the propaganda outlets, the universities, the schools and the official creation myths of the culture. The rallying cry for the Darwinian revolution is “just-so storytelling by faith, not by lab work.” Instead of A Mighty Fortress Is Our God, the official anthem is (to the tune of For He’s a Jolly Good Fellow), “We all take Charlie for granted (3x), which nobody can deny.” Try to deny it and face the wrath of the counter-reformation (see 08/19/2003 headline).