My recent reading has included A Troublesome Inheritance (2014) by Nicholas Wade.
Wade is an experienced science journalist -- he is a graduate of King's College, Cambridge, was deputy editor of Nature, and before going freelance he was both a reporter and an editor at The New York Times, where he wrote frequently about scientific and environmental matters.
His book has the subtitle "Genes, Race, and Human History," which suffices to reveal how fraught is the subject matter. The point he wants to make is that biological evolution continues to change the human genome, and does so at time scales which are relevant to an understanding of history, not just dim pre-history. Evolution by natural selection isn't just about the fossil "Lucy" and her peers. It's about the fellow or gal in the mirror this morning.
Evolutionary psychologists, he says, commonly "teach that the human mind is adapted to the conditions that prevailed at the end of the last ice age, some 10,000 years ago." But that is an arbitrary demarcation. There have been changes in innate human behavior (mark the word "innate" -- his word) -- subsequent to that. Only 3,000 years ago, for example, "Tibetans evolved a genetic variant that lets them live at high altitudes."
This does open up the discussion of race, not as a "social construct" but as a biological fact. Why? Because much longer ago than 3,000 three main sub-groupings of humans had become geographically divided: those of sub-Saharan Africa, of Eurasia from the Himalayas west, and of Asia from the Himalayas east. Those Tibetans notwithstanding, the highest mountains on the planet served as a powerful barrier to genetic mixing, as did the Sahara desert. So it seems a priori reasonable to suppose that to the extent evolution as been active since the geographical spread of the human race across these natural boundaries, that evolution has taken somewhat disparate paths.
The back of the book includes a blurb from Edward O. Wilson, praising Wade for celebrating "genetic diversity as a strength of humanity."
I'll say some more about this book and its thesis tomorrow.
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