Portrait of Theodosius Dobzhansky, photograph, 1943 (Wikimedia commons)

Portrait of Theodosius Dobzhansky, photograph, 1943 (Wikimedia commons)

Theodosius Dobzhansky

JANUARY 25, 2021

Scientist of the Day - Theodosius Dobzhansky

Theodosius (Theodore) Dobzhansky, a Ukrainian-born American geneticist, was born Jan. 25, 1900.  After studying in Kiev (Kyiv), and St. Petersburg, Dobzhansky came to Columbia University in the United States in 1927 to study with Thomas Hunt Morgan, the “Lord of the Flies,” who was a pioneer in using fruit-flies (Drosophila) to unravel the mysteries of genetics.  Dobzhansky became a major figure in forging what is called the modern evolutionary synthesis, or Neo-Darwinism, which was the merging of Darwinian evolution with population genetics.  Population genetics arose in the 1920s as a way of studying the transmission of genes, not from individual to individual, but through an entire population of organisms, and geneticists like Dobzhansky realized that concepts such as “gene pools" and "genetic drift" could explain much of Darwin's theory of natural selection.

Dobzhansky moved with Morgan to Caltech in 1930, and there, in 1937, Dobzhansky published a book, Genetics and the Origin of Species, which did more to explain the evolutionary synthesis than any other single work.  One reviewer called it the single most important book on evolutionary theory to appear since Darwin’s Origin of Species, which is high praise indeed.  Our Library has only a 1947 printing of the second edition and a third edition (1951) and has not yet pursued my suggestion that we obtain a first edition (although I am sure they will), so I show you the title page of my own copy of the second edition (1941) and one of the figures (images above and below).  The illustrations in the book are mostly maps and line diagrams and are not very imposing, but like Darwin’s book, the important message here lies in the words. The second and third editions were considerably rewritten, so it is important for a research library to have them all.

Dobzhansky is also known for a line he first wrote in 1964, and then rephrased in 1973 and used for the title of an article.  It is a sentence that is now in every book of quotations: "Nothing in biology makes sense except in the light of evolution." In the article (fourth image), which appeared in The American Biology Teacher, Dobzhansky explained what he meant, that biology is just a bunch of unrelated facts unless integrated under a rubric, and the only rubric that fits is evolution by natural selection.

Dobzhansky was unusual among prominent Darwinians is that he had a strong belief in a personal God, one who created by evolution rather than by fiat.  He spent the rest of his career at Rockefeller University and the University of California, Davis.  He died in 1975.  The photo portrait that opened this post was taken in 1943.

If you want to see what Dobzhansky looked like when he published his famous  sentiment about biology and evolution, you need look no further than the cover of the issue of The American Biology Teacher that contained his article (fifth image just above).

Dr. William B. Ashworth, Jr., Consultant for the History of Science, Linda Hall Library and Associate Professor emeritus, Department of History, University of Missouri-Kansas City. Comments or corrections are welcome; please direct to ashworthw@umkc.edu.