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A passion for promoting the public good guided geneticist J. B. S. Haldane’s scholarship

A Dominant Character: The Radical Science and Restless Politics of J.B.S. Haldane

Samanth Subramanian
400 pp.
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In 1906, 13-year-old Jack Haldane stood on the floor of Loch Striven, 40 meters under the sea. His father had sent him down to test whether decompression sickness—caused by nitrogen bubble formation in divers’ blood—could be avoided by controlling the rate of ascent. In his leaky suit, Jack knew that each dive carried a risk of drowning. Still, the data they collected was invaluable. A risk-chasing and industrious scientist, his father was developing protocols that would benefit many people. It would be absurd—even immoral, Jack believed—to refuse to be his guinea pig.

Despite holding no formal science degree, the younger Haldane would himself go on to have an extraordinary scientific career, becoming one of the founders of modern evolutionary synthesis and a famous writer of popular science books. In a new biography, A Dominant Character, Samanth Subramanian highlights Haldane’s many accomplishments and considers how his strong moral and political beliefs influenced his scientific work.

After recounting his early experiments with his father, the book follows young John Burdon Sanderson Haldane (nicknamed “Jack” or “JBS”) from his aristocratic origins in North Oxford to Eton College and then Oxford University, where he graduated in 1912 with first-class honors in classics and mathematics. His first great scientific success, we learn, was a 1915 paper on genetic linkage in mice, coauthored with his sister Naomi. Although Haldane had always been interested in genetics, the positive reception of this paper, which Haldane completed while serving in the British Army during World War I, intensified his focus.

Between World Wars I and II, Haldane constructed mathematical formalizations of the laws of Mendelian inheritance and their impact on evolution by natural selection, culminating in his best-known work, a series of 10 papers written between 1924 and 1934 called A Mathematical Theory of Natural and Artificial Selection. During this time, he also formulated two eponymous hypotheses: Haldane’s rule, which predicted that the heterogametic sex (i.e., the XY male or ZW female) of a species hybrid is more likely to be sterile than the homogametic sex; and Haldane’s dilemma, which asserted that the rate of adaptive evolution is limited because advantageous alleles rarely cosegregate efficiently.

Haldane wrote prolifically. He published one of the first textbooks on enzyme function; discussed chemical warfare, religious faith, and air raid precautions in newspapers; argued with racist propagandists in eugenics journals; and even authored a futuristic manifesto (“Daedalus; or, Science and the Future”) that argued that advancements in biology would permit the abolition of disease and the self-direction of human evolution.

Haldane never lost the sense of public duty that he had learned as a young aristocrat, and in 1942, he joined the Communist Party of Great Britain (CPGB) and the editorial board of its newspaper, the Daily Worker. This came at a cost: MI5 kept a file on him for more than 30 years, and he was barred from speaking at certain American universities.

Subramanian explains that Haldane viewed science as the most effective tool for promoting the public good. He designed safer bomb shelters for Blitz-affected London and better mineshaft ventilation, and, like many others of this era, he advocated methods of eugenic family planning. Haldane’s interest in genetics was motivated by a similar concern for human welfare. He wrote, for example, that “a satisfactory theory of natural selection must be quantitative,” but he also felt that it should be useful: Accurate quantification of artificial selection could assist plant breeders throughout the world.

Haldane’s tempestuous relationship with authority led him to leave England for India in 1956. There, Haldane spent the twilight of his career, first at the Indian Statistical Institute (ISI) in Kolkata and later at a special research unit in Bhubaneswar. He explained that this move was his way of protesting the United Kingdom’s repressive actions during the Suez crisis, and he argued that Jawa­harlal Nehru’s newly established Indian state was more conducive to scientific freedom. Nearing retirement, Haldane confined himself to simple but insightful breeding and biometry experiments and continued to write about science in the popular press.

Subramanian admonishes Haldane’s belated rejection of Lysenkoism, suggesting that he demurred because he was reluctant to criticize fellow communists. This criticism lands awkwardly, mostly because Haldane did disown Lysenko—although not as quickly as his anticommunist peers—and eventually left the CPGB, disillusioned by its rejection of “bourgeois genetics.” However, Haldane clearly admired Stalin and tried to reconcile Darwinian evolution with Soviet dialectical materialism (“diamat”) pseudoscience. Subramanian suggests that these mistakes were the predictable result of the political views that motivated Haldane’s best work.

Ultimately, Subramanian’s depiction of Haldane is balanced and modern and should prove engaging to readers interested in the birth of genetics and in the intersection of science and political belief.

About the author

The reviewer is at the Department of Ecology, Environment, and Plant Sciences, Stockholm University, Stockholm, Sweden, and the Science for Life Laboratory, Stockholm, Sweden.