books book reviews

evolutionary biology and psychology books

reviewed by T. Nelson


Human Diversity: The Biology of Gender, Race, and Class

by Charles Murray
Twelve 2020, 508 pages
reviewed by T. Nelson

I n the past ten years, biologists have quietly overthrown the three big postmodern myths that had become ascendant in academia:

  1. Gender is a social construct: demolished by studies of the human brain
  2. Race is a social construct: disproved by the Human Genome Project, which showed that the population really does cluster into groups that correspond to what we would call races.
  3. Class is a function of privilege: deconstructed by modern psychometric testing, now more rigorously solid than ever, which showed that genetics play an important role in future success, while privilege does not.

The so-called blank slate is dead, dead, dead.

Murray spends much of his time trying to mollify readers who, if past history is any guide, will be offended by facts that challenge their orthodoxy. His section on IQ, where he reports that genes are even more important than previously realized, is the most tactful writing I've ever seen. But what he writes is scientifically accurate as well as nuanced: it is now known, for example, that environment has almost no ability to increase IQ, though it can reduce it through physical and nutritional factors.

Murray sticks to the most solid results, leaving evolutionary psychology for (it is hoped) a later book. Murray admits that molecular biologists and other experts will probably find it boring. That's true—most of us know all this stuff already, and none of it is the least bit controversial in biology. But this book wasn't written for us. It's for the general public, and Murray feels it necessary to point out that the brain doesn't really turn into the rainbow of colors as shown on those pseudocolor fMRI scans (although he might be joking, and I should point out the brain does turn a lovely shade of red in carbon monoxide poisoning).

Sociologists may remain in deep denial about the whole idea, but they probably won't read this book because their field has drifted too far away from science and toward a study of ideology.

This book also opens up many areas for useful debate. Some people will accuse Murray as saying that genetics determine behavior. That would be unfair: he's applying a needed corrective in this book. But there's confusion everywhere about what constitutes a trait. I think ‘phenotype’ is sometimes used too broadly. Divorce is not a trait; even calling it a phenotype is a stretch. It's a behavior, so it's questionable whether calling divorce “50% genetic” would make sense.

Likewise, IQ is a composite of many thousands of traits, such as astrocyte number and robustness of cellular and DNA repair mechanisms, but it is also a behavior: the high IQ individual has to learn how to learn and to identify, in the absence of external training, those factors which would impair his or her skills. There are other skills that affect IQ, like those of the kid who sat behind me when we were being tested and somehow got exactly the same IQ score as I did. Ingenuity and 20-20 vision are admirable traits.

It seems to me that saying that things are partly genetic and partly environmental, while useful in establishing causation, is a bit like mixing apples and oranges. If biology is oriented toward medicine, we can treat the apples and leave the oranges to sociology. They can have all the oranges they want. The trick will be knowing which fruit is which.

feb 09 2020


The Neuroscience of Intelligence

by Richard J. Haier
Cambridge 2016, 266 pages
reviewed by T. Nelson

R ichard Haier, a professor emeritus at UC Irvine, thoroughly and calmly debunks the activism-driven myths about intelligence tests. He writes

Modern quantitative genetic studies overwhelmingly support a major role for genes in explaining the variance of intelligence test scores among individuals. [p.66]

About 50% of general intelligence, or g, says Haier, is determined by genetics. As a person matures, this percentage increases, suggesting that the genes controlling intelligence are maximally expressed in early adulthood. One possible explanation is that it is not the basic brain structure that's important, but biochemical or synaptic changes that happen during development. Another is that the rate of brain development varies independently of IQ but reaches a plateau that is fixed at a level that is strongly heritable.

This book is interesting and readable by the general public, though un-provocative; Haier's writing is nuanced, evidence-based, and honest about the level of certainty, and the results showing marked differences in how males and females process information are uncontroversial in science. It's a good example of how a scientist can exert leadership and avoid the hysteria that's increasingly common.

feb 09 2020


Individualism and the Western Liberal Tradition

by Kevin MacDonald
Self-published, no publication date (probably 2020), 525 pages
reviewed by T. Nelson

I'm not sure what to make of this book. The author says that different ethnic groups possess an inbred incapacity for creating an individualistic society and that the influx of immigrants into Western societies will therefore be harmful. This is not something that is supported by science, and there are more than a few unsubstant­iated and inflammatory claims made here, many of which appear politically motivated. Although I can understand the author's frustration, this sort of writing is not helpful; it actually makes things more difficult for those who hope to put evolutionary psychology on a more respectable footing.

Disclaimer: I did not finish reading this book.

feb 09 2020