The behaviour genetics to eugenics to Nazi manoeuvre


Jason Collins


July 16, 2014

Recently, I’ve tended to roll my eyes rather than respond to poor commentary on behaviour genetics. But areview by Kate Douglas at New Scientist, in which she pulls the behaviour genetics to eugenics to Nazi manoeuvre, has pointed out a potentially interesting book.

First, from the conclusion to Douglas’s review (actually, not so much a review but a launchpad):

Behaviour geneticists came to see finding high heritability as a justification for their work. But heredity changes depending on the environment. Grow those tomatoes in a regulated greenhouse and almost all the difference in their height will be thanks to their genes; grow them on a sloping, partly shaded field and the effect of heritability is lower.

Nature and nurture are not distinct, and the complexity of their interactions is increasingly apparent in this genomic age. Heritability can’t even be reliably estimated in humans using twin and adoption studies, the method of choice for behaviour geneticists.

All this undermines the supposition that heritability tells us about the cause of a behaviour. In fact, heritability is almost entirely meaningless.

I haven’t yet met a behaviour geneticist who doesn’t understand that heritability can vary with environment. Just look at Eric Turkheimer and friends’ work on heritability of IQ among different socioeconomic groups. The change in heritability across environment tells us something. And if heritability measures are robust across environments (as it is for IQ for most socioeconomic groups), that tells you something too.

But moving on, Douglas’s review is of a new book, Misbehaving Science: Controversy and the Development of Behavior Genetics by Aaron Panofsky. The blurb on the book suggests it might be better than the review, and could contain some interesting history on the debates in the field.

Behavior genetics has always been a breeding ground for controversies. From the “criminal chromosome” to the “gay gene,” claims about the influence of genes like these have led to often vitriolic national debates about race, class, and inequality. Many behavior geneticists have encountered accusations of racism and have had their scientific authority and credibility questioned, ruining reputations, and threatening their access to coveted resources.

In Misbehaving Science, Aaron Panofsky traces the field of behavior genetics back to its origins in the 1950s, telling the story through close looks at five major controversies. In the process, Panofsky argues that persistent, ungovernable controversy in behavior genetics is due to the broken hierarchies within the field. All authority and scientific norms are questioned, while the absence of unanimously accepted methods and theories leaves a foundationless field, where disorder is ongoing. Critics charge behavior geneticists with political motivations; champions say they merely follow the data where they lead. But Panofsky shows how pragmatic coping with repeated controversies drives their scientific actions. Ironically, behavior geneticists’ struggles for scientific authority and efforts to deal with the threats to their legitimacy and autonomy have made controversy inevitable—and in some ways essential—to the study of behavior genetics.