I’ve been proven wrong. Sometimes, after seemingly endless conversations on Internet message board threads, something important really is learned definitively by the participants. I was highly skeptical that this could happen. But following a looooong discussion of 1,000+ posts on the BioLogos message board, it did!
I offer sincere congratulations to all, and apologies for doubting you. The challenge then becomes to retrieve that something from the tangle of words and present it clearly.
In his book Adam and the Genome, BioLogos “Fellow of Biology” Dennis Venema sought to persuade his fellow Christians that genetic science had disproven the traditional idea of a “bottleneck” of two human ancestors in the near or very distant past.
The main players in the discussion include geneticist Richard Buggs of Queen Mary University in London, biologist Ann Gauger of Discovery Institute, computational biologist Stephen Schaffner at the Broad Institute, computational biologist Joshua Swamidass at Washington University, and of course Dr. Venema.
Over all, this was a highly substantive and educational debate. Bottom line: Venema has backed down.
Article references this Monty Python sketch:
There’s a Monty Python sketch for almost every occasion, isn’t there? Venema, under pressure, appears to have changed his claim.
I guess I really don’t understand what all the furor was. It is absolutely unquestionable that if you go back far enough into the past (2 million years or so), the mathematics cannot exclude the possibility of a bottleneck of two. I’m not sure Venema ever said anything contrary to that. The point of what he said, and I think Buggs and @Agauger would agree, is that the mathematics tells us that it is highly improbable (excluding miracles) that humanity began with a population of two roughly six thousand years ago. I do think Venema overstated the case when he compared the level of certainty to that of a heliocentric solar system, but why it took months of discussion is puzzling to me. Am I missing something important, @swamidass?
Thanks for finding this one! When you post a link that it is critical to give some context on content, and ideally some of the central quotes as well. That people who are entering into the conversation can follow what is happening.
I have already posted this article back on BioLogos. Frankly, I think it’s a travesty.
The writer concludes that Venema’s book is wrong. This is Venema’s most recent statement on the matter:
^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^ Dennis Venema writes:
I’ll cut-and-paste this from the backchannel thread where Buggs, Swamidass, and I have been discussing the evidence. Here’s my position at present.
"We’ve concluded that a two-person bottleneck is not ruled out before 700 KYA. (edited to add this: the context here is an instantaneous drop to 2, immediately followed by explosive population growth).
[Paraphrasing: In other words: a two-person bottleneck could have happened more than 700 thousand years ago (i.e., KYA). G. Brooks]
We’ve agreed that there is no positive evidence for such a bottleneck, only that current methodologies cannot rule it out.
[Paraphrasing Again: Genetic evidence does not rule out that a 2-person bottleneck could have happened more than 700,000 years ago. The molecular noise beyond 700,000 years ago masks the ability to detect the usual markers for such a bottleneck. G. Brooks]
I (and others) have made the point that a bottleneck to two hominins before 700KYA will necessarily be taking place on the African/Eurasian landmass, and thus raises challenging questions about how such a bottleneck could have taken place. Hominins are widespread during this time period.
Josh floated some thoughts about how this might have happened, but neither I nor others found the ideas convincing. Richard has not proposed a mechanism (unless I missed something)?
In the absence of a plausible mechanism I don’t see how the formal possibility of a 2-person bottleneck is meaningful. I recognize others might disagree."
Well, that was not clear to anyone at the start of the conversation. Dennis was arguing that the evidence ruled out a bottleneck back as far as 13 mya. Even if he was right, ultimately, about a couple at 10,000 years ago, the arguments he made were erroneous.
In many ways, Denis put forward something much like an ID argument. When our ID friends argue that the evidence points to God’s design, they are ultimately correct too. However, the fact that they are ultimately correct does not mean the arguments are correct, especially when they have math and logical errors. In the same way, Dennis was ultimately correct on a bottleneck 10,000 years ago, wrong about a bottleneck at 2 mya, but made a lot of errors in his argument. Much Like ID, Dennis was correct on somethings, incorrect on others, but made several erroneous arguments, and is now unwilling to clarify those mistakes.
At this point, he is uninterested in clarifying his position in public. I had hoped for a public statement, but that does not look like it is happening. He seems unwilling.
Then we found out he could not make the case farther back than 700 kya.
As you can see, that is an important option for @vjtorley and @Agauger. That makes it an important fact that Dennis just missed.
And I agree that there is no obvious natural mechanism that would cause a single couple bottleneck, without God’s intervention. However, in human origins, many people are wondering about God’s intervention. So that is a red herring.
Also, I’m not allowed to post on the BioLogos forum at the moment, so there is no way to make these points there.
I haven’t followed the conversation closely for quite a while, but I don’t recall Dennis saying this.
I fully realize that you and Dennis have had conversations that the rest of us are not privy to, but this seems like possibly unfair criticism. You bring up the comparison between Dennis and ID friends. Have you ever heard an ID proponent that was willing to admit mistakes, publicly or otherwise, in their arguments?
My apologies, @vjtorley and @Agauger, I haven’t been following conversations here closely lately. Do you find the concept of an Adam and Eve present among other “adams” an important option? I’m more than a little confused by the contention from ID proponents that EC is essentially unbiblical, but an Adam and Eve existing 700,000 years ago rather than 6,000 is more true to Biblical teaching. Neither one is consistent with a literalistic view of the Genesis account, Romans references, or the Luke genealogy.
So, my apologies, he did not claim the last 13 mya, but the last 18 mya. If it was obvious to you that this was false, it would have been good to know it at the time. It took a surprising amount of work to convince him he was wrong on this.
Moroever, his statements about PSMC and MSMC ended up being totally false. Most the chapters he wrote on population size need to be rewritten, because they are riddled with scientific errors. He thought that these methods were effectively testing for bottlenecks, but they have very low power in doing this, often of by two orders of magnitudes (> 100x), and they are particularly bad at ruling out bottlenecks before 10 kya.
It is true that we do not have a genetic sole-progenitor couple in the last 10,000 years, but not for many of the reasons Dennis has put forward for the last eight years. The argument he has been making is in scientific error. We had to do an entirely new analysis to answer the question, because the methods he pointed to (effective population size estimates) are just not good at detecting bottlenecks. That is, now, fairly well established in the literature.
That is not what they found helpful. Remebmer there are TWO things has been put forward:
Ancient genetic sole-progenitorship with Adam and Eve alone, but somewhere between 2 mya to 400 mya. Adam is not among other adams here though. @Agauger and @vjtorley have favored this, probably because of their Catholic starting point.
Option #1, the Genealogical Adam is consistent with the Romans References, the Genesis Account, and the Luke genealogy. It is nearly identical to John Walton’s reading, but avoids several eisogetical mistakes being made by BioLogos right now.
The humanity then Adam framework is consistent with all of those (minus a literal use of the word “day” which is completely unnecessary). What scriptures in Romans do you think are not consistent with it?
I should have been more clear here. I don’t think I’ve read anywhere where Dennis actually said “sorry, I made a mistake”, but he has been willing to at least back-track a bit. To the best of my recollection, I’ve never read any statement from and ID proponent doing the same.
Thanks, I appreciate the confirmation. It was not obvious to me at the time the conversation was first started. Again, I probably should have phrased my comments a little better.
In this scenario, what do you make of the adams and eves that are NOT in A/E’s genealogical line? Would you suggest they are basically without a spiritual component, and therefore without an eternal destination?
My apologies, my brain is very, very tired… I was mentally mixing the two scenarios. Have you had conversations regarding the genealogical ancestry with individuals that insist that “straightforward” Biblical interpretation indicates that A/E were the only humans at the time? If so, have you had any success with it?