But as we have shown at length in this discussion, they do not. They reconstruct ancestral effective population sizes (not census population sizes) by methods that would not detect a short census bottleneck of two even if one had occurred. These methods therefore do not “indicate that we descend from thousands”.
I don’t think I have ever named 10,000 as the size of a pre-bottleneck population in this discussion – I have just been suggesting that it would be large enough for individuals within it to carry substantial polymorphism within them.
I am left wondering why you wrote a book on Adam and Eve at all, if the idea of the human race coming from a bottleneck of two polymorphic ancestors who had several children was not on your radar.
If you don’t mind me asking, what was on your radar? What hypotheses did you consider that would allow a sole pair of human ancestors?
I note that you wrote on page 46 of Adam and the Genome “it is technically possible that a species could be founded by single ancestral breeding pair”.
I am glad that you would write the book differently today, and that this discussion has not therefore been in vain. However, I am still very mindful of the fact that very few of the readers of Adam and the Genome will stumble across this discussion, and the few that do are unlikely to make it through the first 700 posts. I think that we all need to do all that we can to communicate to your readers that a single couple bottleneck in the lineage leading to modern humans is a possibility that is consistent with extant genetic diversity.
That is not actually the model that has been put forward. The substance of several AatG claims are no longer supported, or are now supported by analysis made after your book was published by other people. You were claiming to be presenting settled science, and the evidence that supported it, NOT a hypothesis that would eventually be supported by work on ArgWeaver. That claim turns out to be totally false. The data you were presenting as evidence was not sufficient to make your case. If had not helped you, you would still be struggling to make the case.
Also @agauger to be fair, both @glipsnort and myself have been responsive to this and engaging it long before Richard Buggs entered the conversation. Back in Sept 2016…
Agreeing with a YEC critic, I wrote a fairly detailed acknowledgement of the failure to directly test for a recent single couple in the literature.
Not public but true, I’ve been engaging with scientists across the origins debate to help them start asking and answering questions here. I’ve always acknowledged that the ancient Adam model has not been tested, and have encouraged effort here.
So we have been testing this, at least since Sept 2016, long before @RichardBuggs entered the conversation. The real problem is that this is just hobby for us (we have other jobs), and there was very little visibility on those contributions.
The real contribution of @RichardBuggs has been to press more tightly in on the LD and population reconstruction data, bring some new information to the table (the website on the PSMC bottleneck detection), and also to draw visibility to this question. This is nearly the most read thread on the forums now, it took quite a bit of effort to bring @DennisVenema to the table (and he is only here now thanks to @RichardBuggs). I’m very grateful to his contribution, but @glipsnort and I have been thinking about this problem for a while. I have encouraged inquiry into it, and have put a lot of personal time into answering it as soon a new path forward to tractably test it became available. It is not merely that @RichardBuggs raised the question, or it would have been missed.
I want to emphasize also that @glipsnort is part of BioLogos, even though I am not. Moreover, several Biologos scientists have been following this, very supportive of @RichardBuggs and my correction to the scientific account. So it is important that full credit is given where it is due. There are alot of people who have been unsympathetic to the questions of the Church, but there are several (including with in BioLogos) that have been sympathetic.
Very good questions. Not sure there is a good answer possible.
Remember, he put forward the strawman of the homozygous clone Adam and Eve?
It does not seem he was terribly engaged on the science here. As has been clear for a while (henrycenter.tiu.edu/2017/06/a-genealogical-adam-and-eve-in-evolution/), @DennisVenema presented a selective account that fit with his personal theological views.
I agree. Which is why your public statement is a good idea @RichardBuggs. I hope Dennis is up for signing it.
@gbrooks9
Fair question. But in that case I don’t think my arguments would change many minds. As others on the list have pointed out, an old Adam does not agree with their reading of Genesis, and that won’t change. That is a key issue for them.
@Swamidass
Thanks, Josh. I appreciate the generous words. I’ll tell you what I would most like: positive evidence of a first pair, not just the finding that we can not rule them out past a certain age.
And thank you for the correction of the record. I was not aware of your earlier efforts with @glipsnort on the question of a first pair.
Will you two sign it without @DennisVenema? I agree with Richard that a public statement would be great, especially if Dennis signs it as a clarification for his book. But if he doesn’t want to, will you proceed without him?
I should add to that response, by pointing to something I wrote quite a while back about this. Perhaps there is a good reason to why he should have written that book.
Even in their support, I hope those who agree with Adam and the Genome will do so with humility. Science is a human effort. It is merely our best account of the world, without considering God’s action. Many informed and intelligent people will still reject evolution. If they do so in obedience to their honest understanding of Scripture, they choose the better thing. There is real danger in unwittingly pressing science if it encourages disobedience to God.
Even in their opposition, I hope those who disagree with Adam and the Genome will work hard to understand. I hope they will emphasize the voices in evolutionary creation with whom they most agree, like the many that affirm traditional Genesis interpretations. Even if it is false, evolution is the origin story of our modern world. We need those with whom we disagree to articulate their positions, just as Venema and McKnight have done here. Even if we disagree, they give truthful account of how most scientists understand our evolutionary origins. Reviewing Adam and the Genome
I think those words still stand. The way how @DennisVenema explained the science was truthfully how most scientists understand our origins, even if it did have major errors. And we all benefit when people put together orderly accounts as Dennis did, so that we can then see what evidence and theology others are resting their positions.
I suspect that @DennisVenema did not understand how important it could be to his audience either (1) a recent genealogical Adam or (2) an ancient single-couple genetic origin. I suspect it was not malice, but inattention. As much as he has become the focal point, a large number of people have thought the same thing, and have been equally inattentive.
It seems he made several errors in how he justified his claims. Much of the strong evidence he had evaporated, and he seems to still communicate about it in a way that overstates the evidence (almost like he does not want to admit he made a mistake?). However, without help, he could not support his claims. Even if he was right on all claims (which he is not), he did not put forward the right reasons for why his claims were correct.
Perhaps, that is the value of the book, it has helped clarify how weak these confident claims really were. Many people make these claims all the time, but now we are clarifying what the evidence is really showing us.
It depends. I put forward some revisions to the language. @RichardBuggs has not responded. I suspect people are now waiting on him. It seems the ball is in his court at the moment.
I also want to acknowledge and thank the moderators, @Christy, @BradKramer, @jpm, and @Casper_Hesp. They actually are officially with BioLogos and have allowed a fairly unsettling conversation to progress on the forums. If it is not clear, they have been very fair, and not interfered in what happened here. They deserve credit for this, as this takes a great deal of work and they could have easily shut down this conversation when it has become uncomfortable.They deserve some credit too.
Moreover, even if @glipsnort apparently is not with BioLogos. Both of us affirm evolutionary science, and I do not believe he affirms a historical Adam. While I affirm a historical Adam, I’m not advocating any specific view of Adam. We are involved just to serve the Church with an honest account of the science, regardless of our personal positions.
Really, Joshua, do you think that is the only value of Dennis’ efforts in the book? I get that he made a mistake that needed to be corrected. Is that all that comes out of his writing, in your opinion?
I also really appreciated hearing his back story, as that explains much of what motivates him. I think Adam and the Genome remains an accurate account of how many people see our origins. I also liked a great deal one of McKnights points:
McKnight studies how Paul’s Adam interacts with Jesus. He observes Paul could be reasoning from Jesus to Adam (p. 181). Paul’s Adam, rather than a starting point from which to define Jesus, is instead an explanatory contrast by which to expound a Jesus clearly seen by other means (Heb. 1:1-3); a Jesus who stands alone, without need of Adam. McKnight’s reframing is consistent with the rest of Scripture, which calls Jesus the “cornerstone” (Eph. 2:20), http://henrycenter.tiu.edu/2017/06/a-genealogical-adam-and-eve-in-evolution/
That was a strong point with which I agree, and had not thought of it that way before.
Nonetheless…
Adam and the Genome is best understood as a partial explanation of the relevant evolutionary science. It also explains why some Christians do not affirm a historical Adam, but a better account would explain this without assuming science. http://henrycenter.tiu.edu/2017/06/a-genealogical-adam-and-eve-in-evolution/
That has value, of course, because we need people to tell us how they see origins. That is what Dennis did.
Did you know that there is ancient evidence of seafaring, at least 700 kya? I discovered it during my work on the genealogical Adam. Very interesting and surprising.
@Swamidass
This is the main point I would like to make. With regard to Adam and the Genome, Dennis was pretty much reflecting what I have seen in the literature: many papers, using different methods, that end up with an Ne of 10,000, plus or minus for our population 6 million or so years ago. He did not think of testing for a bottleneck of two directly, but then at least as far as I know, no one else did either. Until recently.
@Swamidass
I had encountered this before also. When I first saw it I discounted it because of the sensationalism. This about sailing to Crete:
“I was flabbergasted,” said Boston University archaeologist and stone-tool expert Curtis Runnels. “The idea of finding tools from this very early time period on Crete was about as believable as finding an iPod in King Tut’s tomb.”
130 kya is the date I have seen, which could have been Neanderthal, but I assume it had to do with the style of the hand axe.
But more evidence is accumulating of seafaring at earlier dates, as you say. The oldest I have seen:
While no remains of a boat used by H. erectus have been found (the oldest known vessels, Stone Age dugouts, are only a few thousand years old), potential evidence of the species’ habitation on isolated islands suggests that it may have been able to travel many miles across the open sea.
In 2008, Russian researchers found very primitive stone tools on Socotra, a completely isolated island more than 150 miles off the Horn of Africa and 240 miles off the coast of Yemen. … The researchers estimate their discoveries to be anywhere from 500,000 to 1 million years old, which is firmly within the time frame of H. erectus.
(Jørn Madsen, “Who was Homo erectus,” Science Illustrated (July/ August 2012), p. 23.)
And about the Everett piece: he is something of a disputed figure. Some think him brave and insightful, others think him wild and a publicity hound. He challenged Chompsky’s theory about universal language, on fairly flimsy grounds, in my opinion. So he is bound to favor a gradual development of language, and boat building in the early Pleistocene would support that.
Please stop mis-using that term. An ad hominem is the use of a personal attack on someone’s character, as the basis of an argument that their claim is wrong. I have done nothing of the sort.
Every time I make a statement you spin it subtly to deflect from what I am saying. I did not simply say “people have motivations for doing research”. I objected to the fact that in this case a specific theological motivation (anti-evolutionism), is being treated as if it doesn’t exist. Statements and research are being treated as if they are objective scientific exercises, instead of apologetic exercises aimed at trying to support a narrative which opposes evolution.
Again, this is a highly selective description of her “engagement with scientific data”. The way she engages scientific data is not a method we should admire.
If her work is so trustworthy, should we accept her anti-evolution views?
I don’t believe she’s intellectually honest. I find that you spend a lot of time these days calling out scientists for (perceived), lack of honesty if they accept evolution, and praising them for honesty if they reject evolution. You set the bar for honesty and evidence very high for anyone who accepts evolution, but very low for anyone who rejects it. This is a curious pattern which does not appear to have a scientific motivation, but I guess it plays well to your intended audience.
As I pointed out, it was not a strawman. It was an argument which several creationist organizations have made; I even quoted them.
The irony in this statement is palpable.
I call it as I see it. This post of yours looks like just another effort to do exactly that; you talk about everything except the point I raised, your theological motivation for wanting sole genetic progenitorship.
Yes, he was more transparent in his motivation.
Yes. I want to know what the scientific data actually says, regardless of whether or not it conflicts with what I believe at present. I will change my beliefs according to the facts.
I used to believe in a global flood. I did my best to explain away the contrary evidence. I was doing apologetics. When I stopped doing apologetics and started seriously looking at the contrary evidence (both from the Bible and from the physical record in the earth), I found I could not sustain my belief in a global flood. I changed my mind. When I do apologetics, I don’t pretend I’m doing science.
You were making a classic ad hominem. You might want to look at the definition. From wiki:
Ad hominem (Latin for “to the man” or “to the person”[1]), short for argumentum ad hominem, is a fallacious argumentative strategy whereby an argument is rebutted by attacking the character, MOTIVE, or other attribute of the person making the argument, or persons associated with the argument, rather than attacking the substance of the argument itself.Ad hominem - Wikipedia
Dismissing an argument because of the motives of a person is an ad hominem. Denying it is ad hominem does not make it so.
Of course I disagree with Ann on evolution. I think she is wrong, and I have also debated with her extensively about common descent. However, I was surprised when she acknowledged when there was evidence for common descent uncovered in that conversation. Regardless, she can be wrong on evolution, and right on this. Can she not? And even if she is wrong, can she not be honest too? She could just be honestly wrong.
For that matter, I do not think @DennisVenema has been dishonest either. He was just wrong.
Yes it is selective, to the specific data we are discussing here. We are not discussing common descent, but population genetics and Adam and eve.
So Everett has always kind of frustrated me. He attributes a lot of views to people that they just don’t hold. This article is pretty frustrating as well. I think most people would grant Erectus had some type of language. Complex speech? No. I think @agauger is spot on about Everett. And me personally I find the evidence for seafaring pretty convincing. But it was defintely not a regular thing so I’m not going to call them seafarers. This is an area I haven’t spent too much time on so who knows what I really think.
At a level suitable for a broad audience, Dennis also spilled a good bit of ink describing the evidence for common ancestry, the various members of the hominid tree, and the reasons why many scientists are dissatisfied with the ID movement.
Since you are also interested in communicating to a broad audience, Joshua, I thought you might have something to say about Dennis’ sections on these other topics. Do you?
