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There’s more genetic diversity within Africa than between Africans and others.

Thandie Newton at TEDGlobal (via curiositycounts)

What does that even mean?

Yeah, that would be some first class science speak right there.

What he’s saying from a scientific point of view is this:

Say you take a sample of 1,000 Africans from all across the continent and a sample of, say, 1,000 Asians from all across the continent and look at 1,000,000 of the places in the genome that vary between individuals. You can compare every single person against every other person and count how may differences there are between every pair of people. You can then make averages - e.g., how many differences are there on average between each pair of Africans? Well, since there are 1,000 Africans that means there are (1,000 x 999)/2 or 499,500 pairs So you count the number of differences for each pair, add them all up, and then divide by 499,500. You can do the same for each pairing of an African and an Asian - for that there are 1,000 x 1,000 or 1,000,000 distinct pairs. You add up the number of differences for each of the pairs and divide by 1,000,000.

What he’s trying to say is that the average number of differences between Africans is higher than the average number of differences between Africans and Asians. That might seem surprising, but there are some logical reasons why it’s so (and I won’t bore you with them - this is already too long and I’m not quite done yet).

Now, there’s a better question for people not interested in population genetics (like, say, everyone but the handful of population geneticists in the world), which is what Ross was getting at - why are you telling us this? What does it matter outside of a scientific perspective? Well, this is an idea that’s often used in support of the mindset that can be grossly (terribly, awfully, potentially even criminally) oversimplified as “we’re really not so different, all of us”. The gist here is that no matter where we are and what we look like we’re actually genetically very similar, and any thoughts we may have about our superiority over or distinctness from another group is unsupported by the scientific evidence. Does that statement really lead logically to the conclusion it’s used to support? I have some thoughts on that, but they’ll have to wait for another time

(via indefensible)

Source: curiositycounts