Bugg’s opinion is at least as strong as Venema’s, since they both rely on peer-reviewed articles. More to the point, Buggs points out reasons for questioning Venema’s assertions using that peer reviewed literature
Peer-reviewed and published:
Genetic Modeling of Human History Part 1: Comparison of Common Descent and Unique Origin Approaches
Ola Hössjer, Ann K. Gauger, Colin Reeves
Genetic Modeling of Human History Part 2: A Unique Origin Algorithm
Ola Hössjer, Ann K. Gauger, Colin Reeves
In BIO-Complexity last year
No, I am not young earth.
Pouncing is in the eye of the beholder. What is straightforward statement of fact to one side can seem exaggerated to the other. Try walking in my shoes at various blogs, even here sometimes to see real pouncing.
The peer reviewed articles state that the effective human population was thousands of people, not 2.
A quibble with the logic here. Two opinions can only be equal to one another if they both rely on equally valid references. Peer-reviewed is a type of publication but does not mean they are of equal merit. They could be but they must be shown to be equally valid references with respect to their merits. Even two references from a high quality journal may not be equally valid if one is a more appropriate reference than the other.
The point is that just because I may use a peer-reviewed article to make make my argument that doesn’t automatically make my argument as good as every other argument ever made.
While it is good that the work was published, BIO-Complexity is not considered a peer reviewed journal in the scientific community. It is an echo-chamber.
According to your published model, how do you get 4,000+ HLA alleles from 2 people in a specific time period with the allele distribution we see today?
That doesn’t make any sense. I can write something completely ridiculous and still cite such articles.
More to the point, Buggs points out only one reason and has a point, but there are a lot of other datas against a single couple being the ancestors of all humanity.
Why a limit it to 6000 years? For HLA genes the paper by von Salome et al. calculated that it took approximately 450,000 years to go from four alleles to hundreds of them. This is based on the gene HLA – DRB1. I Will get you the reference if so desired. Right now I am on my phone and don’t have access to it.
You are holding us to a stricter standard then Venema. He provides no numbers, equations, or calculations in his book.
They were reviewed by experts in genetic modelling? That is what peer-reviewed means to me.
Ican’t say for sure because the identity of the review were’s is not known to me. But based on their comments I would say yes.
You are correct, I should have used more measured terms. I have seen much more exaggerated examples of “pouncing”, both here and elsewhere.
You do have me rather curious, though. If you are not a young earth creationist, do you accept common ancestry of humanity with other primates? If you do accept common ancestry, why is the view of Adam and Eve as the first two humans important to you?
Buggs brings strong arguments against the impossibility of a severe bottleneck because of loss of heterozygosity. It’s clear from experiment and from theory that a sudden sharp bottleneck does not necessarily reduce heterozygosity. Venema’s claim that we could not have undergone a bottleneck of two because it would leave a mark on our genomes is not justified.
There are other kinds of arguments in favor of a larger effective population size, I grant you. Our model is meant to test those kinds of argument by using different assumptions. When our model is complete and programmed we will be able to test many different starting assumptions and see which best fits the data.
What comments did they make?
I am of mixed mind on common ancestry. It is taken as an axiom by most biologists but there is strong evidence against its universality. I am open to either conclusion concerning the historicity of Adam and Eve. I just don’t think it has been adequately proven. And it is a legitimate scientific question, since scientists have made claims that impinge on religious belieffrom a completely prejudiced point of view. See Ayala 1995 The myth of mitochondrial eve.
Welcome to BioLogos.
I’ll be providing a response in the next few days. In the meantime, feel free to chat with the others here. Some of our commenters are well-versed in the relevant science.
Buggs’s opinion makes a few errors, unfortunately. He was kind to email me with his concerns privately, and I have just been too busy to get around to replying. I’m behind on other things that I have already committed to. But, in a few days, you’ll see my thoughts on the matter.
Wouldn’t it be nice if I (and others) could comment on ENV like you are welcome to do here? Just a thought. Best,
Actually Bugg assumes common ancestry and posits that it is possible there could have been a sharp bottleneck of only two individuals if they carried a large heterozygosity from a highly diverse ancestral population, and then maintain heterozygosity through rapid population growth. Are you arguing that Adam and Eve were not the first humans on the planet, but in fact were the human descendants of a previous population of at least 10,000 people?
I don’t know about commenting on ENV. Have you seen the kind of comments we draw on our various Facebook pages? I think the traffic we would draw is slightly different than yours. In the meantime, if you would like to write a response I am sure they would be willing to post it.
I haven’t read all of Venema’s arguments. Does he argue against a bottleneck based primarily on heterozygosity? That strikes me as about the weakest argument one could make.
This is a much broader statement than your previous one. Whether it is true or not depends critically on what timeframe you’re talking about. Clearly, a bottleneck of size two that occurred 500 million years ago would not leave a record in genetic variation today, while a bottleneck of the same size 50,000 years ago would.
I tend to be more circumspect in my claims about ancestral population size than Dennis. I haven’t done a really systematic study, but my strong impression is that a bottleneck of size two within the last several hundred thousand years is incompatible with patterns of existing genetic variation. If you can fit one in within the last half million years I will be surprised, while a million years wouldn’t surprise me. That’s based on the the overall allele frequency spectrum. There may be other data that would provide more constraints.
Thanks, I appreciate your participation here. Could you explain a little more what you mean by “either conclusion”? The way I see it, there are three possibilities (with unequal likelihood):
- Adam and Eve were created by mechanisms unknown from “the dust of the earth” about 6,000 years ago.
- Adam and Eve were historical figures, but only two of a larger population of Homo sapiens on the earth at the time.
- Adam and Ever were allegorical archetypes, and not historical figures at all.
Personally, I see no reason why adherence to any one of the three should deferentially impact my life today and how I live it in response to the direction of the indwelling Holy Spirit.