An Evolving View of Inheritance

Jessica Riskin

In our April 21, 2022 issue, Jessica Riskin and M. W. Feldman reviewed The Genetic Lottery, in which the psychologist Kathryn Paige Harden makes a case that our genes inform our character and success in society, and that these inequities of genetic inheritance should be considered in crafting progressive social policy. To Riskin and Feldman, her argument was eerily familiar: “The idea of a biological hierarchy of intelligence arose alongside the first theories of human evolution. It never goes away when discredited, just changes forms.”

The two are colleagues at Stanford University, where Riskin is a historian of science and Feldman is a professor of biology. Riskin has written for the Review on the development of scientific thought from the Renaissance to Darwin, about which she has also written several books, most recently, The Restless Clock: A History of the Centuries-Long Argument over What Makes Living Things Tick (2016).

Her research into the history of evolutionary theory drew her to Feldman’s lab, which uses statistical models to investigate various ways that evolution operates outside the genome. Feldman, who has just been awarded the Lifetime Achievement Award by the Society for the Study of Evolution, has been central to developing the theories of niche construction—that, by altering their environments, organisms influence the selective pressures of those environments—and of gene-culture coevolution, the process by which culture evolves and may interact with human evolution.

This week, over e-mail, they shared their thoughts about interdisciplinary scholarship and scientific racism.

Lucy Jakub: Your review was a joint work of criticism, bringing the history of hereditarian science and statistics to bear on current research in genomics and inheritance. I wonder if you both could speak to the value of each others’ expertise.

Jessica Riskin: Throughout his career, Marc has been complicating and enlarging the evolutionary picture in big and important ways. To me, a principal theme of his research is that organisms are not purely passive objects of transformation, but actively take part in directing the course of evolution. Related to this, another central theme that I see in his work is anti-reductionism and causal pluralism: that the best way to understand evolutionary processes is not by reducing them to just one cause, but rather by trying to encompass the rich causal variety in evolution. Both themes draw biological explanations and historical explanations closer together again, after a long period of being widely separate. I think the separation was impoverishing on both sides and the reunion is really enriching.

M. W. Feldman: I have learned a great deal over the past three years from my interactions with Jessica, reading The Restless Clock, and collaborating on this review. Although, as an evolutionary biologist, I am in a sense concerned with history, her nuanced individualization of the human aspects of the history of science have been eye-opening for me. It makes me want to work more with her in the future and to hope that one day my writing can be as good as hers.

Marc, you overlapped at Stanford in the 1970s with William Shockley—the Nobel prize-winning physicist and engineer who late in life developed a preoccupation with eugenics—and were among those outspoken in denouncing his pseudoscientific theories of racial difference. Where does Shockley fit into the history described in the review, and how did that controversy influence your own work?

MWF: The connection with William Shockley was critical to my career and intellectual development. I was a PhD student of the great Stanford mathematician Samuel Karlin, who organized periodic seminars on topics at the intersection of mathematics and genetics. When I joined the faculty of Stanford’s biology department in 1972, the great Italian geneticist Luca Cavalli-Sforza had recently joined the Medical School faculty, and we both attended a seminar by Shockley that Karlin had organized. Karlin was an intensely curious scholar who wanted to know what the furor over Shockley was all about—so he invited him to speak.

Luca and I met immediately following the Shockley talk, to which Shockley had actually brought the psychologist Arthur Jensen, whose argument for the innate intellectual inferiority of black people Harden takes pains to disavow, from Berkeley. It was in response to the Shockley-Jensen writings and speeches that Luca and I began to investigate how traits could be mistakenly attributed to genetic causes when they may actually be a result of cultural pressures. We collaborated closely for the next forty years. A major impetus for our papers was always to stress the importance of environmental contingency in the evolution of human traits. So you could say Shockley contributed very importantly to the development of my science, including my collaborations with the evolutionary biologist (and longtime writer for the Review) Richard Lewontin on the interpretation of race and ancestry.

Jessica, in your last piece for us, on Darwin’s Descent of Man, you wrote that “to say that Darwin was ‘racist’ but also ‘a good scientist’ designates a combination of evil and good in his work but doesn’t illuminate it.” There does seem to be a persistent tendency to conflate the values of the scientist with the implications of their scientific ideas. Harden uses her own progressive ideals as a shield against criticism of her work; meanwhile, accusations of racism—for example, in the case of E. O. Wilson—can render scientific debates very personal and charged. How should we be navigating these distinctions, and how relevant are they?

JR: Actually, I don’t think the mistake in these cases is to assume that scientific ideas carry values. I think it’s just the opposite: the mistake is to pretend that there’s such a thing as pristine science, pure of values and interpretive perspectives. Harden and other people in behavioral genetics and sociogenomics claim—as Wilson did in his “sociobiology”—that they’re just giving us the brute facts about the natural causes of social hierarchies. But, of course, their theories are social phenomena as much as the hierarchies they claim to explain. Science is a human endeavor, an element of culture. Lifting from that piece you mentioned on Darwin’s Descent, science is interpretation all the way through, good science and bad science alike, so purity doesn’t make sense, even as an ideal. Or, from an earlier piece on the scientific method, everything we know is known by us; we can’t eliminate ourselves from the picture.

Darwin mostly believed this: he assumed an irreducible, mutual interconnectedness between nature and culture and treated science as one mode of cultural interpretation among others. He drew on every form of understanding he could—history, literature, philosophy, aesthetics. The best of his science came from his awareness that he was making sense of an irreducible, living, self-forming world from within; and the worst came when he lost that awareness and atomized humans into rankable traits. I think the worst science, in general, has often come from a pretense of purity, as in the case of sociobiology and sociogenomics. Instead of aiming for purity, science should aspire to self-awareness and engagement in a larger project of understanding.

In The Genetic Lottery, Harden aims to rehabilitate behavioral genetics from its racist and pseudoscientific baggage. Her approach didn’t convince you, but is there anything of the field that’s salvageable, in your view?

JR: No.

I’m afraid that answer is too short, so let me see if I can make it a little longer! I think behavioral genetics and what people are now calling “sociogenomics” are predicated on a wrongheaded reductionism. Yes, DNA is an essential part of all living things including humans. But that doesn’t mean that DNA causes or explains all aspects of human life, society, and culture.

People involved in behavioral genetics, including Harden, say they’re not being reductive, but they are. Harden emphasizes that she doesn’t claim genes “determine” outcomes or that the environment plays no role, but as we hope to have shown in our review, if you read her carefully, you’ll see that despite these protestations, she is assigning a reductive causal role to genes. The logic of behavioral genetics and sociogenomics is fatally flawed because it rests on a category mistake. The things behavioral genetics researchers are trying to explain are made of ideas, opinions, judgements, social practices, not nucleotides.

MWF: I think there is a danger of a resurgence sociobiological reductionist thinking that is stimulated by social scientists using genetic tools to produce a “field” of sociogenomics. The risk is that classism and racism will sneak back into important components of the public domain, such as educational policy via the pathway of claims about genetic bases for human behaviors.

What are you each working on right now?

MWF: I am working with colleagues in the UK and Europe on evolution and development in the context of our previous work on the Extended Evolutionary Synthesis, and continuing my recent work that incorporates human behavioral strategies into models for epidemic dynamics. I also have new analyses of cultural traits whose transmission among individuals depends on the levels of conformity or anticonformity in their population—that is, the extent to which people embrace the same cultural preferences and behavior.

JR: I’m writing a book about the history of evolutionary theory focusing on the life and career of the French naturalist Jean-Baptiste Lamarck, in which I’ll follow the fortunes of Lamarck’s science from his lifetime up to the present. His ideas were foundational to modern biology—in fact, he coined the term “biology” in 1802, defining the science of life as a discrete field, and he also proposed the first theory of species change, or what we now call evolution. The emblem of Lamarckism became the giraffe, who, in stretching to reach high branches, lengthened its neck and forelegs by tiny amounts; these incremental changes, Lamarck proposed, added together over many generations, produced the giraffe’s distinctive form. Lamarck’s theory languished in exile for over a century, from roughly the 1880s until the 1990s, when the possibility that organisms might transform themselves heritably began re-entering mainstream biology in areas such as epigenetics.

Lamarck’s giraffe represented a mode of science featuring causal complexity, a diversity of agencies, and the fundamentally interpretive nature of knowledge. Banishing the giraffe was crucial to establishing a model of living beings as passive objects of evolutionary transformation, and an accompanying model of science as the reductive account of passive objects, utterly separate from all other forms of knowledge. These models of life and of science have persisted up to today. A history of Lamarckian evolution is also a history of how we understand what a living thing is, and what science is—and how we might understand both a bit differently.