Thanks for your comments. Sorry I’ve been slow to respond.
I feel like I’ve gone over this before, but perhaps a recap would be in order.
In AatG I defend two claims - (1) that as our species, Homo sapiens (anatomically modern humans or AMHs), comes into being, we do so as a population. This is the “heliocentric” quote.
I also say that (2) the dip to ~10,000 seems to be the lowest our lineage experienced over the last 18 MY, based on the methods applied to date.
Both of these statements remain accurate. Our discussion has led us to agree that a 2-person bottleneck for the lineage leading to present-day humans is not plausible within the last 700,000 years or more. This is well before AMHs appear in the fossil record. So, point (1) stands, even if one might differ over just how “heliocentric” that certainty is.
Point (2) also stands. I’ve learned a bunch from our discussions - and I’m grateful for it! - but nothing we have uncovered provides any positive evidence for a 2-person bottleneck (or even a sub-~10,000 bottleneck) at any point over that timeframe. So, it still would seem that the ~10,000 number was the low point.
What we have established is that a very sudden bottleneck to 2 followed by exponential population growth might escape detection using current methods if it occurred before 700,000 years ago. That is interesting, but it does not change the points I made in the book. It still seems that ~10,000 was the low point based on current methods. In order to say that those methods might have missed the real 2-person bottleneck event, I have asked you (or others) to propose how such an event might have taken place.
Unless I’ve missed it - and I might have - I have not seen you propose any mechanism for a precipitous drop to 2 followed by exponential population growth. I don’t see this as plausible. @Swamidass gave it a go earlier, but that showed the difficulties. It can’t reasonably be genetic isolation of a population, since this is happening in Africa/Eurasia, and there is no way to geographically isolate populations on that landmass (the only way to assure genetic isolation). So, it would have to be an event that (a) kills off all but 2, but then somehow also allows for exponential growth immediately thereafter.
That’s not biologically plausible. At least, not to me, nor to any biologist I’ve discussed it with (except for @Swamidass, perhaps). Perhaps you have a model in mind to explain it that I am missing?
In other words, if what you are proposing is not biologically plausible I don’t see a pressing need to address it.
Now, if I was writing AatG today, I would include a discussion of this conversation, and what we’ve learned from it, to be sure. What I would also do, however, is discuss why I don’t find the “sudden catastrophic bottleneck to 2 followed by explosive exponential growth” hypothesis to be compelling.
… And now for something completely different:
Another thing that I have been meaning to ask for a long time in this conversation is this. Several years ago, you were widely quoted by the Discovery Institute and other ID sources as claiming that the identity of the human and chimpanzee genomes was around 70. It seems your original article on the subject is no longer online, but here’s how the DI quoted it at length:
Do you still think that humans and chimpanzees are around 70% identical at the DNA level? If so, why? If not, why not? Seeing as this is @glipsnort 's area of expertise, he might also be interested in your thoughts. I’ve been meaning to ask you this for months, and I keep forgetting to do so.