Sergei Sergeevich Chetverikov (1880-1959) Russian population geneticist

Sergei Chetverikkov, Russian population geneticist

Sergeĭ Sergeevich Chetverikov (=Tschetwerikoff) was a Russian entomologist, an expert on butterflies, and a pioneer of population geneticists. Born into a well-educated, professional family, Chetverikov entered the University of Moscow in 1900, graduating six years later. He continued at the university as a research fellow, receiving an advanced degree in 1909. Afterwards, he taught entomology at the Higher School for Women in Moscow from 1909 to 1919. In 1921, Chetverikov accepted a research position at the Institute for Experimental Biology in Anikovo, near Moscow. This was run by N. K. Kol’tzov. At the institute, Chetverikov continued his naturalist collecting, especially butterflies and moths. He also undertook experimental and theoretical research into the diversity of mutations in natural populations. At the same time, he taught both genetics and biometrics. Chetverikov was recruited by Kol’tzov for his knowledge of flies. These animals were rapidly becoming the standard organism in genetics research. Chetverikov played a key role in establishing a Drosophila research group at Kol’tzov’s Institute when fly stocks from Thomas Hunt Morgan’s famous laboratory first arrived in 1922.

I wrote this article for an encyclopaedia some years ago, but it does not seem to have been published. Hence, here it is. I’ve added only a few links internally. Joe

Chetverikov’s research career effectively ended in 1929, at its height. He was arrested, probably for suspicious organizing activity, and banished from Moscow. He was helped neither by a history of arrests for antigovernment disturbances while a student nor by close affiliations with the Morgan school of chromosomal genetics and Mendelian genetics. Joseph Stalin’s isolationist policies purged Western influences from Soviet science and culture. In genetics, this purge accompanied the rise of Trofim Lysenko and a theory of inheritance that emphasized dialectics between organism and environment and the inheritance of acquired characteristics. Chetverikov was one of hundreds of experimental geneticists either sacked, imprisoned, exiled, or murdered.

In exile, Chetverikov moved to Sverdlovsk, working in a zoo until 1932. He then moved to Vladimir to teach mathematics in a junior college. In 1935 he became a professor of genetics at the University of Gorky. His activities in Gorky are not well known as he deliberately kept a low profile under the watch of suspicious authorities. He did undertake some small-scale research into natural selection using silkworms. In 1948, at the age of 68, his position was officially terminated in another Lysenko-inspired purge of geneticists linked with Western ideas. Chetverikov remained mentally active until his death, although in his final years he was hampered by poverty and poor health. His brother Nicholas cared for him until his death at the age of 78.

As an evolutionary and population geneticist, Chetverikov argued that natural populations maintained a large reserve of recessive genetic mutations, soaking them up like a sponge. In an evolutionary context, these provided raw material for new variety. They fueled microevolution. As an experimentalist, Chetverikov used inbreeding techniques to reveal the extent of diversity in recessive mutations. His ideas challenged traditional views that mutations simply were laboratory artefacts, broken forms of the normal genetic information. Instead, populations could be considered as pools in which many alleles swam. The frequency of each allele shifted according to demographic changes, such as migration, and through natural selection. Along the same lines, when he was studying wild populations in their natural habitats, Chetverikov emphasized the importance of variation within polymorphic species.

Chetverikov is best remembered as the author of a 1926 theoretical paper, translated in 1961 as “On Certain Aspects of the Evolutionary Process from the Standpoint of Modern Genetics.” This is a classic presentation of fundamental concepts in population genetics, and it earned him recognition as the forgotten fourth contributor to a trio of mathematical population geneticists (Ronald Fisher, JBS Haldane, and Sewall Wright) responsible in the 1920s for combining Mendelism and Darwinian natural selection into a neo-Darwinian synthesis. In his paper, Chetverikov argued that (1) mutation is the source of variation in evolution; (2) inheritance follows a particulate (i.e., Mendelian) pattern rather than blending or dialectics; (3) genes should be understood as a series of variant alleles, and the frequency of those alleles is key in determining the rate and direction of evolutionary change; and (4) geographic isolation can have an important impact on the evolution of populations.

The fate of Chetverikov’s writing is a good example of communication barriers in science. Few read his paper when it first appeared because the journal itself was poorly distributed outside Moscow. Moreover, except for a short summary in English published in tandem, those unable to read Russian had to wait for German, French, or English translations. Private translations, however, circulated in several research centers outside the Soviet Union (e.g., J. B. S. Haldane in London). Selected passages, translated by Theodosius Dobzhansky, first appeared in print only in 1959. A full English translation did not appear until 1961. During his forced retirement, Chetverikov revised his famous paper, dictating corrections and commentary despite failing health; it was never published.

Chetverikov’s widest influence came through his teaching and his students, some of whom emigrated to the West, including N. P. Dubinin, N. V. Timoféeff-Ressovsky, B. L. Astaurov, D. D. Romashov, and S. M. Gershenson. Theodosius Dobzhansky credits Chetverikov with introducing him to Drosophila genetics.

Chetverikov Bibliography

Adams, Mark. 1980. Sergei Chetverikov, the Kol’tsov Institute, and the evolutionary synthesis. In Mayr, E. & Provine, W. (eds.). 1980. The Evolutionary Synthesis: Perspectives on the Unification of Biology. Cambridge, Mass.: Harvard University Press, pp. 242-278.

Chetverikov, S. 1961. On certain aspects of the evolutionary process from the standpoint of modern genetics. Proceedings of the American Philosophical Society 105, 167-195, translation of 1921 paper.

Joe Cain