Richard Lewontin

Richard Charles Lewontin (March 29, 1929 – July 4, 2021) was an American evolutionary biologist, mathematician, geneticist, and social commentator. A leader in developing the mathematical basis of population genetics and evolutionary theory, he applied techniques from molecular biology, such as gel electrophoresis, to questions of genetic variation and evolution. He was a self-described Marxist.

In a pair of seminal 1966 papers co-authored with J. L. Hubby in the journal Genetics, Lewontin helped set the stage for the modern field of molecular evolution. In 1979, he and Stephen Jay Gould introduced the term "spandrel" into evolutionary theory. From 1973 to 1998, he held an endowed chair in zoology and biology at Harvard University, and from 2003 until his death in 2021 he was a research professor there.

From a sociological perspective, Lewontin strongly opposed genetic determinism.

Lewontin was born in New York City to parents descended from late 19th-century Ashkenazi Jewish immigrants. His father was a broker of textiles, and his mother a homemaker. He attended Forest Hills High School and the École Libre des Hautes Études in New York. In 1951 he graduated from Harvard College with a BS degree in biology. In 1952, Lewontin received an MS degree in mathematical statistics, followed by a PhD degree in zoology in 1954, both from Columbia University, where he was a student of Theodosius Dobzhansky.

He held faculty positions at North Carolina State University, the University of Rochester, and the University of Chicago. In 1973 Lewontin was appointed as Alexander Agassiz Professor of Zoology and Professor of Biology at Harvard University, holding the position until 1998.

Lewontin worked in both theoretical and experimental population genetics. A hallmark of his work was an interest in new technology. In 1960, he and Ken-Ichi Kojima gave the equations for change of haplotype frequencies with interacting natural selection at two loci. Their paper gave a theoretical derivation of the equilibria expected, and also investigated the dynamics of the model by computer iteration. Lewontin later introduced the D' measure of linkage disequilibrium.

In 1966, he and J. L. Hubby published a paper that studied the amount of heterozygosity in a population. They used protein gel electrophoresis to survey dozens of loci in the fruit fly Drosophila pseudoobscura, and reported that a large fraction of the loci were polymorphic, and that at the average locus there was about a 15% chance that the individual was heterozygous. (Harry Harris reported similar results for humans at about the same time.) Previous work with gel electrophoresis had been reports of variation in single loci and did not give any sense of how common variation was.

Lewontin and Hubby's paper also discussed the possible explanation of the high levels of variability by either balancing selection or neutral mutation. Martin Kreitman was later to do a pioneering survey of population-level variability in DNA sequences while a Ph.D. student in Lewontin's lab.