Considering a Sapien Adam 200 kya

[swamidass (S. Joshua Swamidass)]

@John_Harshman

This is more important for me to understand. Why does this not work with out of africa? In this case, Adam and Eve would be at the rise of Sapiens, in Africa.

Oh, I thought the garden had to be in the Middle East somewhere. If it’s in sub-Saharan Africa, don’t a number of the early Genesis stories have problems? Come to think of it, I guess there are serious problems with any story that puts Adam and Eve much before the origins of herding and agriculture. Adam’s curse, Cain and Abel, founding cities, and all that are just out. Are you cool with that?

We are not talking about me, so it doesn’t really matter if I am cool with it.

Yes, you either have to ditch the agricultural setting of Genesis, or infer a lost history of agriculture. This is a problem. You also do have to move it to Africa.

Reasons to Believe (@AJRoberts), who would go this path in their thought experiment, would say that there was a lost history of agriculture, and that upper Africa is “close enough” to the Middle East.

@John_Harshman

This seems to be the implication of a TMR10A=180kya.

The meaning of “this” is unclear. Could you clarify? I don’t understand what the current scenario is. Are you proposing a bottleneck in Africa down to 10 or 100 individuals, into which the descendants of A&E integrate? This all needs to be articulated more clearly.

The “this” is just what I described earlier:

@swamidass

If Adam and Eve produce a large population before the interbreeding starts, then we can guarrantee that we all get soem of their DNA, if they are far enough back in time. My estimate right now is that if they were 200 kya, there would have to be one pure-blooded Adam-decendent mixing with 4 non-Adam descendents for this to work. We would all have about 20% of our genome from Adam in that case.

10 alleles is 5 people, so I’m seeing my numbers are off here. Sorry, it is late at night. So if 4 alleles comes from Adam and Eve, then 6 would have to come from others. So that would be a mixing ratio of 1:1.5. I’m sure we can derive time dependent scale that tells us what percentage of our ancestry would have to come from a place other than Adam and Eve this way.