Think about what this means People who have, say, three black great-grandparents and five white ones, will vary widely in how black they look, and this likely affects how they identify. But there are also invisible markers of ancestry - of the sort you would expect maybe were visible only on an X-ray if you looked carefully. Those could easily break the other way. You could easily get someone who looked white (and thus, probably identified as white), but were "black on the inside", in terms of their less visible characteristics.

Yet the algorithm sees through all that, and manages to see what you feel like? Correctly classifying Shaun King as black and Tom Jones as white? From a 8x8 X-ray picture?

The people who insist that "race is real" should be the most confused by these results, since we know how fuzzily identity is coupled with ancestry, especially in the main groups studied here, black and white Americans.

I'm much more prepared to believe, for instance, that there is something catastrophically bad going on in medical image dataset collection, than I am that self-ID race is nebulously predictable from almost nothing.

Africa is very, very, very genetically diverse compared to the rest of the world. I don't think there exists a population which doesn't contain genes for lighter skin.

I think race labels make some sense in a social/cultural context: In America we can call someone "black" when they are 75+% white, because for their entire childhood/life, socially, society at large treated them similarly as they treat people who are "100% black".

But race doesn't make sense in a genetic context. It's probably far more absurd than defining the difference between an accent vs dialect vs language. Even though there are clear differences between individuals/families, the boundaries are absolutely arbitrary.