Charles Darwin formulated his evolutionary theory at a time when it was commonly assumed that different races of humans had different natural levels of intelligence. Darwin did not even feel the need to defend this premise, writing in The Descent of Man: “The variability or diversity of the mental faculties in men of the same race, not to mention the greater differences between the men of distinct races, is so notorious that not a word need here be said.”¹

This common assumption was very amenable to the idea of a gradual evolutionary ascent. In 1774, the Scottish anthropologist Lord Monboddo had argued that there was really no clear demarcation line between humans and apes: some apes had government and others music, and some races of men were speechless savages and others had tails. Yet even in Darwin’s time, new facts were coming to light that rendered the theory more tenuous. Almost a century after Monboddo wrote his book, it was becoming clear that there really were no races of men with tails — and no unbroken descent from “civilized man” down to the apes.

Darwin Evolves on Race

The change of opinion seems to have been mainly the result of empirical evidence. That’s not surprising: every time a European encountered intelligence and virtue in a person of a different ethnicity, the imagined barrier must have eroded a little. And as non-Europeans obtained more rights and integrated into European and colonial societies, their humanity would have been all the more undeniable, which would in turn enable them to obtain more rights and integration. It was a positive feedback loop.

This process can be observed from Darwin’s own writing. For example, Darwin admits in The Descent of Man: “The American aborigines, Negroes and Europeans differ as much from each other in mind as any three races that can be named; yet I was incessantly struck, whilst living with the Fuegians on board the “Beagle,” with the many little traits of character, shewing how similar their minds were to ours; and so it was with a full-blooded negro with whom I happened once to be intimate.”²

The choice of examples is telling. The “full-blooded negro” was probably the “very pleasant and intelligent” black man in Edinburgh who taught Darwin taxidermy, as described in Darwin’s autobiography. The Tierra del Fuego natives who impressed Darwin with their humanity were not typical locals, but men who had lived in England for several years and learned some English.³ We have trouble connecting with people across cultural divides, and Darwin would naturally see humanity more clearly in an Anglicized foreigner than in a “savage” with a spear (or someone under the degradation of slavery). 

Furthermore, the Age of Exploration was over. The world was getting smaller by the day, and it was easier to spot a fanciful tale. The testimony of a single doctor would no longer be enough to make one believe in a race of savages who had tails or could not speak — if such creatures were real, their existence would be easy enough to verify. 

The Modified Racial Evidence 

Darwin thus could not deny that the intelligence and moral character of even the “lowest savages” proved that there was in fact a large gap between mankind and the highest animals. This was a challenge to his theory, but one he found simple enough to deal with. He wrote:

We must also admit that there is a much wider interval in mental power between one of the lowest fishes, as a lamprey or lancelet, and one of the higher apes, than between an ape and man; yet this immense interval is filled up by numberless gradations. Nor is the difference slight in moral disposition between a barbarian, such as the man described by the old navigator Byron, who dashed his child on the rocks for dropping a basket of sea-urchins, and a Howard or Clarkson; and in intellect, between a savage who does not use any abstract terms, and a Newton or Shakespeare. Differences of this kind between the highest men of the highest races and the lowest savages, are connected by the finest gradations. Therefore it is possible that they might pass and be developed into each other.⁴

The important thing to notice here is that Darwin was not merely conceding racial disparity to the conventional wisdom of his day, as some have claimed. Rather, he was using it to rescue his theory. Darwin admitted that the obvious mental gap between men and apes was a barrier to accepting his theory. But he argued that it was not an insurmountable barrier, because you could at least still observe a gradual ascent both before and after the gap — presumably, the races in the middle had simply gone extinct.

A Biogeography of Race

Darwin also used the idea of innate racial differences to support the biogeographical argument for evolution:

The races differ also in constitution, in acclimatisation, and in liability to certain diseases. Their mental characteristics are likewise very distinct; chiefly as it would appear in their emotional, but partly in their intellectual, faculties. Every one who has had the opportunity of comparison, must have been struck with the contrast between the taciturn, even morose, aborigines of S. America and the light-hearted, talkative negroes. There is a nearly similar contrast between the Malays and the Papuans, who live under the same physical conditions, and are separated from each other only by a narrow space of sea.⁵

The invocation of the narrow space of sea between the Malays and the Papuans is significant, because this is the “Wallace line” (as it is still called) named after the biologist Alfred Russel Wallace, who independently formulated the theory of evolution by random variation and natural selection. At a certain line in Indonesia, he noticed, the characteristically Asian fauna began to give way to Australian fauna. Wallace (like Darwin) interpreted the match between biological differences and geographical barriers as evidence of evolutionary history. The idea was that after Australia and Asia had split apart, significant cross-fertilization between them became difficult or impossible, so the lifeforms on the respective continents followed different evolutionary paths. 

In The Descent of Man, Darwin seems to be applying this pattern to the supposed mental difference between the races to imply that the human races had evolved according to the same processes which govern lower life forms. Once again, Darwin is not making a concession to the racism of his day — he is recruiting it. 

A Damaged Picture

While evolutionary thinkers of the 18th century could see a smooth transition from apes to Man, Darwin was forced to present the story of human evolution as a painting with a large hole torn out of the canvass in the middle: sure, parts were missing, but you could still see what the picture was supposed to be based on the parts that were there.  

Or at least, that Darwin thought were there. Further data on race and intelligence would emerge in the next century, and ruin even that part of Darwin’s painting. We’ll look at the final demise of scientific racism in my next post. 

Editor’s note: See also, “Monkey Men: The Fables That Inspired Evolutionary Theory.”

Notes

1. Darwin, Charles (1871). The Descent of Man, pages 109-110. Murray.
2. Op. cit. 232. 
3. Op. cit. 34.
4. Op. cit. 35.
5. Op. cit. 216-217.