David Reich

And then over time, we detected additional mixture events like this modern human into Neanderthal and then this

other ones I didn't even talk about, like super divergent lineage filling into Denisovans and like all this other stuff.

And we still say, oh, the whole genome says Neanderthals and Denisovans are sisters, so that's the truth.

And we've like patched it all together and gotten it all to work.

And oh, you look at the mitochondrial DNA and the Y chromosome and they have this odd pattern and it's improbable, but we can get that to work if we invoke natural selection, you know, things like this.

So...

you patch it all together, you make these, it's a little reminds one of sort of what happened in the ancient world where there was this idea that the sun revolves around the earth, but it doesn't quite explain the movements of the planets properly.

And so in order to get the movements of the planets to work right, you know, the Ptolemian astronomers would have made up these

these special like extra rotations and movements to make everything work about right.

And it was such a convoluted model.

And then when Copernicus and colleagues suggested instead that actually what's happening is everything's revolving around the sun, that it simplified things and made things every so much simpler.

So the situation that was happening is that as sort of as

astronomical information accumulated, it kept being contradictory to the standard model, but it could be made to work by proposing another complication and another complication and another complication.

But this is not as fantastic as proposing that everything revolves around the sun rather than the earth, but it is much simpler.

And actually it explains many, many things.

I mean, nobody's thinking about this model right now.

So, I mean, I don't know.

It's just, I think that...

I don't know, it seems like obviously a very natural model to me.

That's a great question.