stabilizing selection, modern synthesis, books "Factors of Evolution: the Theory of Stabilizing Selection" (1946) and "The Organism as a Whole in its Individual and Historical Development" (1938)
He is remembered, among other things, for Schmalhausen's law, which states that a population at its limit of tolerance in one aspect is vulnerable to small differences in any other aspect.
In 1901, Schmalhausen graduated from the First Kiev Gymnasium [uk] and enrolled at Kiev University, but was expelled a year later after taking a part in student disturbances. In 1902 he resumed his university studies at Kiev in the faculty of biological science. Around 1902 he became acquainted with the founder of the Russian school of evolutionary morphology, Alexey Severtsov (1866–1936).
In 1904, Schmalhausen, under the guidance of Severtsov, completed his first scientific work on the embryonic development of lungs in the grass snake. He graduated from the university in 1909.
In 1910, he married Lydia Kozlova, a French language teacher at Kiev Women Gymnasium.[3]
He published his most well known book, Faktory Evolyutsii in 1946. This was translated by Theodosius Dobzhansky and appeared in English as Factors of Evolution: The Theory of Stabilizing Selection in 1949.[4]
On 23 August 1948 he became victim of order 1208, one of a series signed by Minister of Higher Education in the USSR, Sergei Kaftanov [ru], which led to the mass dismissals of many university professors. This destroyed his career, as it removed his professorship and also decreed the destruction of his books and research projects. This action came about due to accusations of Weismannism and pro-Morganism, and of promoting the neo-Darwinian theory of evolution by natural selection, at a time when Trofim Lysenko and his followers were emphasising a process of heredity that focused on interaction with the environment and the inheritance of acquired characteristics along Lamarckian lines. (Lysenko put his theory into practice in agriculture, claiming to have improved wheat using Lamarckian techniques. Lysenkoism played a major role in Stalin's politics, stressing that hard work led to improvement in future generations.)
This section needs expansion. You can help by adding to it. (August 2024)
Schmalhausen's law is a general principle that a population living at the boundary of its tolerance, in extreme or unusual conditions with regard to any aspect of its existence will be more vulnerable to small differences in any other aspect. Therefore, the variance of data is not simply noise interfering with the detection of so-called "main effects", but also an indicator of stressful conditions leading to greater vulnerability.[5]
References
^ abcLevit, Georgy S.; Uwe Hossfeld; Lennart Olsson (2006). "From the "Modern Synthesis" to Cybernetics: Ivan Ivanovich Schmalhausen (1884–1963) and his Research Program for a Synthesis of Evolutionary and Developmental Biology". Journal of Experimental Zoology. 306B (2006): 89–106. doi:10.1002/jez.b.21087. PMID16419076. S2CID23594114.
^Wake, D. B. (1996). Schmalhausen’s evolutionary morphology and its value in formulating research strategies. Systematic Biology as an Historical Science. Memorie della societaItaliana di scienze naturali e del museo civico di storia naturale di Milano, 27, 129-132.