Richard Lewontin: Demolition Man of the Modern Synthesis

Richard Lewontin, Lewes, Sussex, 1971. Photo: Stuart Newman.

The first public lecture I attended as a new graduate student at the University of Chicago in 1965 was by the evolutionary biologist Richard Lewontin, who died on July 4 at age 92. Its subject was Darwin’s theory of evolution. I had met Lewontin five years before, as a teenager in New York enrolled in a genetics course he taught on Saturday mornings to lucky high school students. In the interim, Darwin’s stock had been rising. He was beginning to replace Freud in both the academic and public arenas as the age of anxiety slipped into a period of social conflict. After a subsequent few decades of war, riots, plagues and disasters, the time would be ripe for Darwin’s natural selection to be described by the Tufts University philosopher Daniel Dennett as “the single best idea anyone has ever had.”

Lewontin’s talk did not go as I had expected, however, and many others in the hall seemed a bit stunned as well. Instead of extolling Darwin’s theory as the revealed mechanism for uncovering life’s mysteries, he described it as projection onto the natural world of the ideology of the Victorian haut bourgeoisie, the self-proclaimed fittest specimens in their own struggle for existence.

Two things had happened just previously to turn Lewontin from a golden boy of the Darwinian mainstream (his Ph.D. advisor Theodosius Dobzhansky was one of the founders of the “modern evolutionary synthesis”) to what would ultimately be its most prominent scientific demolisher. The first was meeting up with the ecologist Richard Levins, a self-described “fourth-generation Marxist,” a subtle and ironic thinker who reveled in the contradictions encountered in attempts at causal accounts of complex systems. Levins and Lewontin would eventually publish The Dialectical Biologist (Harvard, 1986), a set of mostly separately written essays, with contrarian leftist takes on such topics as “The Problem of Lysenkoism,” “The Commoditization of Science,” and “The Organism as the Subject and Object of Evolution,” the last a particularly influential contribution of Lewontin’s.

The second unsettling factor was a set of experiments Lewontin had just performed with his biochemist colleague Jack Hubby. These showed that the extent of genetic variability (i.e., differences between individuals in the versions of the genes they contained) in natural populations (fruit flies in their case, but the British geneticist Harry Harris also showed it in humans) was much greater than predicted by Darwinian population genetics. This would have seemed like a small thing to most observers of the natural world, but it shook up the modern synthesis, where unsparing culling by selection for superior fitness ruled.

Lewontin’s population genetics colleagues took this as a challenge, and in hundreds of papers devised mathematical models to explain the high variability without relinquishing the gene-determinist core of their paradigm. Lewontin took a different tack, moving beyond gene-centrism almost entirely. His growing political commitments blended with his scientific critique as he saw hereditarian ideas (based on an increasingly nebulous gene concept) misapplied to human society, to supposed racial differences in intelligence, to animal behavior, to agriculture, and to evolution itself. In his 1974 treatise The Genetic Basis of Evolutionary Change (a title whose implied determinism he came to regret) he stated that “[t]o concentrate only on genetic change, without attempting to relate it to the kinds of physiological, morphogenetic, and behavioral evolution that are manifest in the fossil record, is to forget entirely what it is we are trying to explain in the first place.” Later books, some written with colleagues, such as Not in Our Genes: Biology, Ideology and Human Nature (1984), Biology as Ideology: The Doctrine of DNA (1991), It Ain’t Necessarily So: The Dream of the Human Genome and Other Illusions (2000), had titles that better captured his thinking.

Moving from Chicago to Harvard in 1973, he joined up with the paleontologist and evolutionary theorist Stephen Jay Gould to write, in 1979, an immensely influential paper “The spandrels of San Marco and the Panglossian paradigm.” The standard Darwinian idea was that every trait of an organism had been individually “selected for” for survival value. But in the “Spandrels” paper, selection for one feature (the reduction in the size of the face that occurred over human evolution, for instance) was proposed to lead (typically by readjustments in embryonic development) to something entirely incidental, without any obvious adaptive advantage (the human chin, in their example). They generalized this to suggest that many organismal features had evolved by means other than natural selection, and only afterwards did their bearers find ways to put them to use. The idea that organisms are agents that can creatively make use of traits that were not explicitly selected for to invent new ways of life, initiated a way of thinking (encapsulated in Lewontin’s “Organism as the Subject…” essay mentioned above) which led other biologists to found the subfield of evolutionary biology known as “niche construction.” The modern synthesis completely ignores this side of the origin of species.

We are accustomed to having our major scientists provide specific explanations for things that didn’t previously have them: the motion of the planets, the structure of atoms, the function of the immune system. Lewontin’s contributions, in contrast, were mainly deconstructive. But by dismantling the assumptions of the prime metanarrative of the past century – the gene-centric Darwinian synthesis whose object of study was passive organisms molded by an unyielding external environment – he earned a place in the pantheon of the most important scientific thinkers of our time.

Stuart A. Newman, Ph.D. is a professor of cell biology and anatomy at New York Medical College, and co-author (with Tina Stevens) of Biotech Juggernaut: Hope, Hype, and Hidden Agendas of Entrepreneurial Bioscience (Routledge).