Adam, Eve and Population Genetics: A Reply to Dr. Richard Buggs (Part 1)


(Dennis Venema) #893

Here you are: link


(Peaceful Science) #894

As I’ve already stated, this depends on several assumptions about God’s action in human origins.

Relaxing those assumptions we cannot know for sure. It is not science at this point, but we cannot know for sure. I certainly do not know as certainly as I know that the earth moves around the sun.


(Peaceful Science) #895

You are right @DennisVenema. I was in error. It looks, instead, like it was about 9% Neandertal and 91% Sapien, like he had 1 great-grandparent neandertal.


(Dennis Venema) #896

I think it was tested, but I don’t recall offhand. Time to re-read more papers. :slight_smile:


(George Brooks) #897

I will agree to your 3 points of stiupulation … if you will agree to include the 10,000 year time frame (at least once each time) in your future summaries of the options.

Every time you list the options without including at least one that respects the 10,000 year time frame, you are materially contributing to confusion in minds of at least one segment of the readership, and inevitably recreating the requirement to more clearly explain what you meant some time down the road…


(Dennis Venema) #898

Yes, the paper is a really cool one because the data indicate really recent Neandertal ancestry for that individual. It also shows that the hybrid great-grandparent seems to have interbred with Homo sapiens, and so on, down to this individual. I.e. the hybrid and his or her later offspring were accepted within the Homo sapiens group.


(Peaceful Science) #899

And I suppose my point is that this is very strong evidence. We do not have comparable evidence for Denisovans. We do not even know for sure if they looked more like an ape or a human. Their teeth were certainly very ancient looking.


(Steve Schaffner) #900

I believe that a least a third of the Neandertal genome can be found somewhere in today’s human population.

That is correct. Gene-rich regions are less likely to show interbreeding, suggesting the action of purifying selection.


(Steve Schaffner) #901

As the linked abstract states, the finger bone provided the genome, while the tooth contributed mtDNA.


(Peaceful Science) #902

Do you know a reference for that? It would be great to have it.

Except HLA and CRISP gene regions are included. Once again, does raise the specter of convergen-evolution in these regions. Though that is not all the regions for neandertal.

Well there you go. Thanks.


(Peaceful Science) #903

It is pretty clear where I stand here:

I might occasionally speak in shorthand, where in context it is clear what I mean. I have no problem taking to task people who quote mine me as supporting a YEC position.


(Andrew M. Wolfe) #904

Hi @DennisVenema,

Honest question from a complete amateur here. I hope it’s pertinent. In your Evolution Basics posts on BioLogos that I read some years ago, I found the arguments from incomplete lineage sorting to be lucid, persuasive, and interesting. The very idea that there might be analogous genetic variation across different species, even through complete lineage sorting, was mindblowing to me (and intuitive, once I thought about it). Are we now saying that a bottleneck of two — even millions of years ago, shortly after the chimp-human split — can accommodate lineage sorting data without postulating these miraculous, so-called mosaic genomes?

Please forgive me if this is an elementary question covered elsewhere in this 892-comment thread. It would be wonderful if you could give me a link and say, “I already explained that here: [link].” Fwiw, I did a search for Incomplete Lineage Sorting and it only brought up a single snippet — the one above from Richard in post #12. Unfortunately, searching for “ILS” gives me dozens of posts with the word “detaILS” in it. :slight_smile:

Thanks for any response you may have time to give. I suppose it would be great to hear from any of the other biologists on the thread, too, but I’m directing the question to Dennis because it’s something he’s written a good bit about and I’m confused why it no longer seems to be relevant to the bottleneck question.


#905

I guess the point I was trying to make is that very often they weren’t hidden assumptions. They were part of the creationist argument.

It might be helpful go back a little bit in the conversation. This is what I had to say before:

“If the 2 person bottleneck crowd has to retreat to time periods where population models are necessarily ambiguous then we go back to the burden of proof problem inherent in that bottleneck hypothesis. In order to work past the null hypothesis you have to have models that will detect a bottleneck if there was one. If the models and data do not allow you to reject the null hypothesis, then you stay with the null hypothesis.”

I was talking about the bottleneck hypothesis, and the null hypothesis that goes with it. The point I was trying to make is that if you start with the evidence there is no reason that you would never get to a conclusion of a bottleneck. The evidence simply doesn’t lead there.


(Peaceful Science) #906

Sure, but the same could be said of the hypothesis against a bottleneck. It is very symmetric ignorance we have here.

Not really. YEC scientsits almost uniformly hold that the genus Homo is human, not just sapiens.

The insistence that “human = Homo sapiens” seems to be disproportionately common amongst EC writers. It is very out of step with current thinking in the field.


#907

It is asymmetric with respect to the last 200,000 years. There is strong evidence (i.e. strong statistical significance) for a large continuous human population over that time period and no evidence for a 2 person bottleneck during that time. For the periods that our models and evidence can give us a reliable answer it doesn’t support a 2 person bottleneck.

That simply isn’t true. Here is a chart mapping out the diversity of opinions among YECs:


reference


(Peaceful Science) #908

Of course I agree with that.

Love the chart. Where did you get it from?

Nonetheless, they usually put Neandertals with Homo sapiens as “humans” too. Everything on the table here appears to be at the border of Homo genus. There is debate about what is in Homo and what isn’t, and that is well known about YECs. It is also strong evidence that there is not sharp dividing line (or else why would they argue about it?).

The confusion about defining Homo, however, is different than claiming “human = Homo sapiens” which I do not think any of the listed people here make that claim.

YECs can believe a lot of crazy things, as can we all, but “human = Homo sapiens” does not appear to be one of the beliefs we can pin on them. That appears to be more of an EC failing.


(George Brooks) #909

@T_aquaticus

Its been my experience that YECs are very quick to call Neanderthal “Homo sapiens with arthritis”.
And if pushed, they would probably call the other variants recently uncovered as more adaptations than evolutions…


#910

At times it can feel like a constantly moving target, the purpose of which is to keep beliefs from being pinned down. Prior to all of the work that has gone into human genetic diversity I doubt you would have found very many people in the ID/creationist community who would have been on board with Adam and Eve being part of H. erectus with all of its ape-like features. It would be very interesting to poll the readership at ENV and see if they are ok with a 2 person bottleneck (i.e. genetic Adam and Eve) at 500,000 years ago within the H. erectus species.


#911

It’s been a while since I saw that old YEC chestnut. The first Neanderthal fossil did appear to have rickets which YECs misinterpreted as rickets being responsible for all of the physical differences between Neanderthals and modern humans. The truth is that the specimen may have had rickets AS WELL AS many non-rickets associated features that differentiated it from modern humans.


(George Brooks) #912

@T_aquaticus, yes, of course it had rickets. And of course it is not Homo sapiens.

Old, “mostly” inaccurate positions are a specialty of that community… YEC’s minimize the importance of differences between Homo [something] at the drop of a hat. If there is evidence of genetic sharing … they will definitely erase any distinctions. It’s their methodology.

… even if we were to show we had genes from Homo erectus!