Richard Buggs: Adam, Eve, and Human Genetic Diversity

[John_Harshman]

@thoughtful

Not if Eve’s eggs have created differences though, right?

Yes, there are any number of crazy notions that would save the appearances. But why? Why simulate common descent so carefully, down to the last detail?

[swamidass (S. Joshua Swamidass)]

Well, that isn’t my view. But if RTB proposes it, why not just be clear about how the evidence does and doesn’t impinge on them?

[sfmatheson]

@swamidass

Hehe. It is a question.

Yeah, and so is “Hey do you think that superaliens built a Pret a Manger on the moon?” Along with “hey do you think that a human who doesn’t believe in my god is a person with diminished intellectual capacity”? Labeling something a question isn’t even the tiniest step toward justifying a conversation about it.

@swamidass

Fransisco Ayala asked the question and published an analysis in PNAS. Was he a few steps from madness too?

Yes he was. Entertaining this question is madness-adjacent, and I told you that in the question about superaliens.

Maybe ask yourself this question: is someone going to write an “analysis” of whether ash borers are all descended from a single breeding pair? Where are the “questions” about whether there were unicorns on the ark?

All Christians in this conversation should IMO understand that these questions are not rational apart from a particular way of reading not-so-credible ancient scripts in order to satisfy morally-discredited religious teachings. Pret a Manger on the moon is less irrational.

[swamidass (S. Joshua Swamidass)]

@sfmatheson

@swamidass

Fransisco Ayala asked the question and published an analysis in PNAS. Was he a few steps from madness too?

Yes he was. Entertaining this question is madness-adjacent, and I told you that in the question about superaliens.

Okay I see what you are saying.

Yes, this is madness adjacent. A lot of the work addressing this is madness. The key thing for me here is:

1. I want to engage the question with empathy, even though it isn’t my question. Doing so builds trust where it is greatly needed.

2. I don’t want to descend into madness myself, not meaning to say that everyone asking the question is mad, but most the work here is madness.

I don’t think I’ve personally crossed the line into madness here. Engaging this question with honesty and rigor is all that I am advocating here.

[John_Harshman]

@swamidass

• They still want to minimize interbreeding, and this analysis is a way to determine how much interbreeding, at most, is required.

What’s the point of minimizing interbreeding?

@swamidass

It is part of what stimulated RTB to propose a new de novo model of AE (Mosaic Eve). You could argue that isn’t a single couple bottleneck either, but it is from their point of view.

Of course it’s a single couple bottleneck. It just has the problem that it requires a miracle whose only purpose is to simulate a larger population. God the deceiver again.

@swamidass

There is a history of people saying that their theological beliefs on sole-progenitorship were totally ruled out by particular genetic evidence (effective population size), requiring a minimum population size of 10,000. That wasn’t true, in fact it was never the consensus view.

Why should anyone care about this history, and how does it justify changing the definition?

@swamidass

Even if trans-species variation ends up putting a minimum population size of 15, that is orders of magnitude less than 10,000.

So what? The goal is to match Genesis. 15 is as bad as 10,000 for that purpose. Anything more than 2 is equally contradictory to the reading of Genesis they’re trying to support.

@swamidass

But if RTB proposes it, why not just be clear about how the evidence does and doesn’t impinge on them?

Not clear what you’re saying here. Omphalism is a dead end; do you disagree?

[swamidass (S. Joshua Swamidass)]

@John_Harshman

@swamidass

• They still want to minimize interbreeding, and this analysis is a way to determine how much interbreeding, at most, is required.

What’s the point of minimizing interbreeding?

That’s a good question to pose to them.

@John_Harshman

@swamidass

But if RTB proposes it, why not just be clear about how the evidence does and doesn’t impinge on them?

Not clear what you’re saying here. Omphalism is a dead end; do you disagree?

That’s a theological argument. Not all cases where the scientific analysis diverges from reality imply a deceptive God. Each case has to be looked at carefully on its own terms.

[glipsnort (Steve Schaffner)]

@swamidass

Well, it does. They are using the term differently, and they have a right to do so. Sole progenitor, in this discourse, includes theological meanings. Scientists do not have the right to tell theologians what they mean by terms in theology.

Which is just fine. They can define theological sole progenitorship (or theological coleslaw) any way they like. For that discussion, bottlenecks and allele frequencies have no meaning. But if they’re saying something this:

@swamidass

Theoretical and empirical studies of genetic bottlenecks show that large diverse populations can be descended from a single couple. Commonly-used methods of reconstructing past human population sizes would not point to a single couple bottleneck even if it were true. There are a range of historical scenarios by which a single couple could be the sole progenitors of present day human genetic diversity.

then they’re asking a question about genetics, and in that context, scenarios that include admixture do not feature a bottleneck of size two.

[John_Harshman]

@swamidass

Not all cases where the scientific analysis diverges from reality imply a deceptive God.

Again, it’s not clear what you mean. What scientific analyses are supposed to be diverging from reality here? I’d say that almost every case of omphalism implies deception. There is very little necessary appearance of age anywhere.

[swamidass (S. Joshua Swamidass)]

@glipsnort

@swamidass

Well, it does. They are using the term differently, and they have a right to do so. Sole progenitor, in this discourse, includes theological meanings. Scientists do not have the right to tell theologians what they mean by terms in theology.

Which is just fine. They can define theological sole progenitorship (or theological coleslaw) any way they like.

Keep in mind though that we are talking about the interaction between their theology and science. So it is not legitimate to take their use of that term, discard their definition, and declare it in conflict with the evidence.

You are an expert in genetics @glipsnort, but I don’t think you have the expertise in their theological position to judge this. The interaction between their theology and genetics is a place I have unique expertise. I can show you with certainty and evidence that their scientific claims were consistently misunderstood because of rigidity on this particular term, and others.

[sfmatheson]

@swamidass

Keep in mind though that we are talking about the interaction between their theology and science. So it is not legitimate to take their use of that term, discard their definition, and declare it in conflict with the evidence.

Did someone do that?

@swamidass

The interaction between their theology and genetics is a place I have unique expertise.

This does not absolve you of professional scholarly responsibility in noting when “theology” asks questions that put scientists in the position of needing to say: “that might not be impossible, but the question is irrational.”

[swamidass (S. Joshua Swamidass)]

@sfmatheson

Did someone do that?

Yes. And no, it is not productive to publicly prosecute them on this.

@sfmatheson

This does not absolve you of professional scholarly responsibility in noting when “theology” asks questions that put scientists in the position of needing to say: “that might not be impossible, but the question is irrational.”

I’m very clear that these are questions arising in the Church, from concerns that most scientists don’t hold.

Some will consider them irrational questions, but they just arise from different belief systems than us, and like all questions from the public I want to answer them with honesty and rigor.

[glipsnort (Steve Schaffner)]

@swamidass

Keep in mind though that we are talking about the interaction between their theology and science.

I’m talking about the bit you have quoted above, part of which I quoted. That statement is entirely within the purview of science, unless you’re suggesting that they’ve also got theological definitions of ‘genetic bottlenecks’ and ‘genetic variation’. They’re welcome to claim that Neanderthals weren’t ‘theological humans’ – I have zero interest in their theological claims. What they’re not free to claim is that ancestors of modern humans went through a genetic bottleneck if some of those genetic ancestors were Neanderthals living on a different continent.

[swamidass (S. Joshua Swamidass)]

@glipsnort

What they’re not free to claim is that ancestors of modern humans went through a genetic bottleneck if some of those genetic ancestors were Neanderthals living on a different continent.

The way you understand it is not what RTB, WLC, Gauger etc. is claiming. Keep in mind they are all making slightly different claims too.

@glipsnort this is just a failure to translate. I suppose we can discuss this another time. Rather not beat a dead horse here.

[swamidass (S. Joshua Swamidass)]

So I’ve had a chance to listen to the whole lecture. It is interesting that he is soft pedaling on some key points. In particular, given some of the claims he makes here, he really should have noted the caveats from HLA / trans-species variation.