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Notes taken on 2022-05-27 and 2022-05-28.
In "Natural Selection and the Brain" (Ch4) Gould summarizes a conflict between Darwin and Wallace.
Wallace was a "hyper-selectionist", meaning that he saw natural selection as the only cause of evolutionary change ("every part of every creature is fashioned for and only its immediate use"). As a result, he did not believe natural selection could explain the human brain.
He argued that contemporary "savage" (i.e. non-European) people, as well as the recent ancestors of Europeans, had cognitive potential that went unrealized before society developed to a certain degree (e.g. to compose music or write philosophical literature). He was unusual among his European contemporaries in believing all "racial groups" to have the same fundamental cognitive potential (Gould describes him as a "non-racist" but still a European chauvinist).
These human cognitive abilities, latent until revealed in developed societies, could not have conferred a survival advantage in undeveloped societies. Therefore they could not have been selected for. Therefore, the human brain could not be accounted for by natural selection alone (it must have been providentially guided).
Darwin saw it otherwise. A structure in an organism might have arisen because it conferred a certain reproductive advantage. But the potential of this structure is not exhaustively described by its "purpose" in the context of the structure's first emergence. The title of Gould's book alludes to a striking example of this: the Panda's "thumb" is not a thumb at all, but a bone that was likely selected for conferring advantages in locomation, and only later evolved to confer advantages in eating bamboo.
Wallace's view is comparable to Dr. Pangloss's in Candide. {Connect to Hobsbawm note about Panglossian bourgoise}
In "Darwin's Middle Road" (Chapter 5), Gould quotes Darwin attributing the eureaka moment during which natural selection occured to him to a reading of Malthus' "Essay on the Principle of Population". Silvan Schweber has reconstructed the other reading Darwin did immediately before reading Malthus. This included Comte, Stewart, and Quetelet. Through Stewart, Darwin absorbed the Smithian idea that order can emerge through the pursuit of self-interest, and transposed this idea into the realm of biology. Gould quotes Marx to this effect, and notes that Darwin nevertheless remain a key influence on Marx's own work (which was of course critical of Smith in many respects). The distinctively bourgeois origins of the idea are irrelevant for assessing its truth or fruitfulness in evolutionary theory (Gould quotes Kautsky for a more general formulation what others call the "genetic fallacy").
Panda's thumb (p128). Humanity has existed for 1/100000th (10^-5) of the time the earth has existed. 50,000 years versus 5 billion years. For 3 billion years, the most complex form of life was an algal mat. 600 million years ago the Cambrian explosion of forms of animal life occured.
Panda's Thumb, Chapter 15, "Doctor Down's Syndrome". Ontogeny recapitulates phyologeny was the theory of the day (e.g. embryonic development repeated the stages of evolution of the organism's ancestors). But the racist theory of the time went further to a fourfold parallelism between: human fossil, normal adult of "lower races", white children, white adult affilicted with "atavisms" like Down's Syndrome (trisomy-21)
Down asserted that people with Down's syndrome were prone to mimicry, a view that accorded with the belief prevalent among contemporary Europeans that the achievements of Chinese civilization must have been imitative.
The internal coherence of this racist theory unraveled when East Asian people with trisomy-21 came to the attention of Europeans, leading to such absurd classifications as "Mongol Mongolians". Latterly, it has been discovered that an analagous chromosomal variation occurs in chimpazees.