Part 1: Skin in the Game
Summary
This chapter begins with a review of our current understanding of genetics and points out that,
it is never easy, and mostly impossible, to predict the physical manifestation of the gene that encodes it - the phenotype from the genotype.
Rutherford explains even the 'textbook examples' that we give to school kids such as eye and hair colour are far more complicated than we teach (I'm reminded of Terry Pratchett's "
lies to children"). He makes the obvious but easily overlooked point that when we talk about eye colour or hair colour, or skin colour, although we use sweeping statements like "brown" they actually come in a huge range of colours and when you think about it for even a few seconds it seems pretty obvious that a lot of genes would be involved. He also notes that Africa has a huge range of skin colours (which makes sense when you consider it's got the greatest genetic diversity of humans of any continent).
Rutherford then starts to get into the history of racism and notes that while there have been large ancient empires, most notably in Europe the Roman Empire, skin colour wasn't a big deal. He notes that,
these were times of extensive slavery and colonial expansion. Religious and ethnic stereotypes and prejudices abounded. But their criteria for subjugation were not the same as ours today, and pigmentation has not always been a primary determinant of character or descent.
And that,
The emergency of a scientific (or more accurately, pseudoscientific) approach to human taxonomy coincided with the growth of European empires... It is far easier to sell the case for occupation and enslavement if you are persuaded that the indigenous people are different, have different origins, and are qualitatively inferior to colonists.
Rutherford goes through a short list of some of the classifications humans have been placed into.
- Karl Linnaeus proposed five sub-species of human: Homo sapiens Afer (Africa), Americanus, Europoeus, and monstrosus (which included mythical and strange humans such as feral people, wolf boys, etc). These categories were described not just on skin colour but "racist value judgements" that resulted in H. sapiens Afer being described as "lazy", Americanus were "zealous and stubborn" and Europoeus were "gentle, inventive and governed by laws".
- Johann Blumenbach, came up with five categories, but different: Caucasian (white Europeans), West Asians and North Africans, Ethiopians (sub-Saharan Africans), Mongolians (East Asians) and Native Americans. He primarily based these classifications on craniometry but did use skin colour and came up with the familiar categories of white, black, yellow, brown and red.
- Johann Gottfried von Herder decided that the categories were specious and were on a continuum.
- George Cuvier thought there were three races: Caucasian, Mongolian and Ethiopian which were ranked in that order from most to least superior.
- Carlton Coon, an influential 20th century anthropologist, thought there were 5 classes: Caucasoid, Mongoloid (East Asia and the Americas), Australoid (Australia), Capoid (southern Africa) and Congoid (from the Congo).
As Rutherford points out,
The continual failure to settle on the number of races is indicative of its folly. No one has ever agreed how many races there are, nor what their essential features might be, aside from the usual sweeping generalisations about skin colour, hair texture and some facial features.
He goes through some of the research used by scientific racists that race is a real and scientifically-based classification, including the ABO system of blood categorisation which was found to form clusters around the world and argued that it proved historical races. This research overlooked (not surprising, as it was published in 1919) the fact that the same ABO blood system is found in gibbons and old world monkeys, so significantly predates the divergence of
H. sapiens.
More recently, the genomic revolution has led to more 'evidence' or racial groupings.
Rosenberg et al. (2002) found genetic clusters broadly matching geography. This has been used by scientific racists to justify their views. But Rutherford points out that while the data reflects the geographical barriers to reproduction that "hinder interbreeding", these same data also show,
long, clear gradients between all of the clusters, and no unambiguous way to say where one cluster ends and another begins.
He also explains that while the five clusters that the racists latch onto are pretty spurious as they say they match the five groups determined by Blumenbach and Coon. The paper found a number of clusters (I haven't read it, but am assuming they did some form of cluster analysis and if that's the case one form of the analysis lets you tell it how many clusters you want). As Rutherford points out,
There is no a priori reason to settle on five clusters as being the definitive categorisation of humans, and deciding to do so because it corresponds with an earlier yet debunked classification is simply affirming pre-existing biases.
He also makes the important point that all these analyses are analysing genotype, not phenotype and as he repeatedly points out,
it is not at all easy to extrapolate phenotype from genotype.
He illustrates this with a brief discussion on the facial reconstruction based on skulls. He says that the validity of these reconstructions is unclear and there's a lot of uncertainly about whether they resemble the person in life. This surprised me, as did his comment that,
as far as I know, the test of this hasn't been done: a reconstruction of a living person based on a scan of their skull.
While I'm not particularly surprised a reconstruction hasn't been done from a scan, I'm surprised no-one has used at least one of the many bodies donated for scientific research to test how accurate facial reconstructions are. I'd be really interested to know if anyone has any insights into this.
The final section is a discussion of skin pigmentation. Rutherford explains that skin colour varies even at the same latitude so,
Obviously and significantly, other factors are at play, aside from pigmentation in relation to sunlight.
He ends by pointing out that,
there is more diversity in pigmentation in Africa than in the rest of the world
Something that has only been recently become the subject of study. These studies have revealed that the variation, like that of blood types, have been present long before the evolution of
H. sapiens and that
The most up-to-date science... makes it clear that DNA is a bewilderingly inscrutable predictor of skin colour.