Since many don’t see to be aware what of creationists’ models even include, and I’m still learning about it and haven’t studied it much myself, I thought I’d start a thread to clear up confusion and to learn more.
I admit I need to read through the whole second paper yet. It’s long.
I meant there is no such thing as a perfect eye color and skin tone, because that is the opposite of the view they hold to. So yes, to be clear we both agree there is such a thing as front-loaded variation. That and being created in the image of God erases racism.
Yet, Adam and Eve could have been created massively heterozygous. We have argued for over a decade that they could have been created with “designed diversity”. We have previously shown that a vast amount of genetic variation could have been pre-programmed into their genomes. This could logically provide the genetic basis for: 1) our human gifts and talents; 2) the many forms of human beauty; and 3) the various ways people have rapidly adapted to new habitats.
It is also claimed that the currently observed human allele frequency patterns could not arise from a single couple. The logic here is that, since there were only four sets of chromosomes in Eden, all variants would have had an initial frequency of either 25%, 50%, or 75%. Today, most allelic variants have frequencies in the range of 0–10%. Therefore, it is claimed that observed human diversity disproves a literal Adam and Eve.
In this paper we have critically examined these arguments. Our analyses highlight several genetic mechanisms that can help reconcile a literal Adam and Eve with the human allele frequency distributions seen today. We use numerical simulation to show that two people, if they contain designed alleles, can in fact give rise to allele frequency distributions of the very same type as are now seen in modern man.
The means by which eukaryotic species’ genotypic and phenotypic diversity arose has been debated for over a century. The comparison between mitochondrial DNA clocks and nuclear DNA clocks reveals the necessity of created heterozygosity in accounting for genotypic diversity within ‘kinds.’ Created heterozygosity in combination with presently observable natural processes (the CHNP model) appears sufficient to explain the vast phenotypic and genotypic diversity observable today, and the CHNP model makes testable predictions by which its strength can be evaluated further in the future. Thus, speciation on the young-earth timescale is not only plausible; it is quickly becoming scientifically superior to any other explanation for the origin of the rich diversity of life on this planet.
This particular sort of created heterozygosity demands an incredible (and I use the literal meaning here) level of crossing over during meiosis in order to account for modern allelic diversity. Do they deal with that problem?
Two humans that are heterozygotes for each gene can only carry 4 total alleles between them. There are way more than 4 common alleles for many human genes. Starting with just 4 alleles can not explain modern human genetic variation.
Idk. I have to first understand what you’re asking , but that’s why I’m here - it helps me understand what I’m reading from them better if people point out their objections. Could you explain the problem further? I obviously can google meiosis.
This is an attempt to account for the full diversity of human alleles, as well as their frequencies, starting with just 4 alleles in the first pair. While it’s true that there are only 4 possibilities at each position in the genome (A, C, G, or T), new alleles must be formed by recombination. Suppose at some spot in the genome Adam has a sequence AAAAAA in one of his chromosomes and GGGGGG in the other, while Eve has CCCCCC and TTTTTT. During meiosis (that’s the process that makes gametes, i.e. sperm and eggs), the corresponding chromosomes trade sequences at various spots. That’s called “crossing over”. A given sperm might end up as AAAGGG, while an egg might end up as CCCCTT. If the combination results in Cain, he has the genotype AAAGGG on one chromosome of a pair and CCCCTT on the other. Then when he develops sperm cells, one of them might end up with AACCGT. And so on, with all possibilities of the 4-letter alphabet possible in various of A&E’s descendants. The problem with this is that I have grossly exaggerated how much crossing over occurs on a chromosome. There are generally only a few crossing over events, possibly one or two, in a chromosome containing hundreds of millions of positions. Worse, the crossing over isn’t evenly spread; there are hotspots. In order to produce what we see from only two individuals, the rate of crossing over would have to be many orders of magnitude greater than observed. It’s yet another required miracle.
Why couldn’t they each have two of the four of these (forgive me, I have no idea which combinations have a basis in reality yet) ACGTAC, CGTACA, GTACTA, TACGAT and then have lots of children? Maybe I’m not understanding the concept.
Either way, the miracle you’re asking for seems like it just has to happen when they were created, since creation is a miracle anyway. (I’m assuming you didn’t read the linked paper?)
Examining the Designed Gametes Model
We examined the logical outcome that would arise if God
individually designed each of the gametes (more accurately the
gametogonia) within Eden, with each gamete (or gametogonium)
potentially having its own unique genotype. We tested to see if
this could possibly generate the allele frequencies observed today.
The logic of this analysis is described in the Results section.
We first explain that two designed people could have millions
of individually designed gametogonia, and that these diverse
gametogonia could represent a gene pool essentially equivalent
to the gene pool of a large human population. We then illustrate
this using numerical simulations. We initially simulated 50
offspring that carried designed alleles from a first couple, which
would have been transmitted through 100 genetically independent
gametes (50 sperm and 50 eggs). Mendel then tracked the initial
designed alleles, plus accumulating mutational alleles, though a
200-generation biblical framework…
Figure 7 shows that the Designed Gametes Model enables a literal Adam and Eve to generate, in just 200 generations, and without any ancestors, an allele frequency distribution very similar to what is seen today.
Apparently. Of course they could have any four sequences at all. I just picked the easiest ones to explain the process. The result would be the same.
No, it’s not something that can happen when they’re created. It has to happen when they form gametes, and then when their children to, and their grandchildren, etc. for quite a long time.
But now you introduce a completely different model, the designed gametes model. That requires no crossing over and could produce any distribution of alleles at all as long as Adam and Eve have hundreds of children. But that’s an entirely separate question from designed heterozygosity. You have changed the subject.
I forgot to mention that we have to start all over again with Noah, and a maximum of 10 alleles (Noah, Mrs. Noah, and the three boys’ wives). Did they all have designed gametes too?
I assume similarly you’d have 3 couples that each could have a variety of differences, both inherited mutations as well as originally created differences.
I don’t think you’re understanding the difference between heterozygosity and designer gametes. And I don’t think you understand how a bottleneck leaves evidence in allele frequencies.
Maybe not, but I don’t know how I don’t understand it if you don’t provide more information. I did read the paper.
Some fraction of the pre-Flood genetic diversity would be lost due to the genetic bottleneck of the biblical Flood. However, population geneticists have known for decades that even the most extreme bottleneck (i.e., two people) can capture a significant amount of a population’s pre-bottleneck diversity, assuming the bottleneck only lasts for one or just a few generations and is followed by rapid population re-growth (Nei et al. 1975). This has also been demonstrated using computer simulations of a single generation Flood-type bottleneck involving just three founding couples (Carter and Powell 2016). Therefore, there is no problem with the Flood scenario in terms of preserving most of the originally designed variants, even though there would be some loss of diversity. For example, if Noah’s three daughters-in-law were distantly related, the Ark-borne population could have carried up to 80% of the pre-Flood diversity (Carter and Powell 2016). Even in a worst-case scenario (where Shem, Ham and Japheth married their sisters), nearly 60% of the pre-Flood diversity would still have been retained (Carter 2018). Thus, while some created diversity would be lost at the Flood, Noah’s family could have easily carried millions of polymorphic alleles.
But did you understand it? One problem is that the initial frequency of any allele, after the bottleneck, can be no less than 1/10. It would take a long time to lose that signature.
Crossing over is an integral part of pairing homologous chromosomes together during meiosis–without it, there is massive nondisjunction, monosomy, trisomy, etc. (simply put, lethal).
These crossovers are used for mapping genes on chromosomes–this is only one level beyond the most basic Mendelian genetics, so it’s pretty ridiculous that you have such strong opinions without knowing about this.
To assort all of that heterozygosity, there would have to be a massive increase in crossing over. Otherwise, the alleles that were linked to each other in the beginning would tend to stay together for a very, very long time.
All that linkage would massively reduce the variation that you think would be produced.
Some of it. TBH, not all of it. That’s why I ask questions. I figure you guys are tough critics - and the hardest questions actually make it easier to learn IMO.
Why?
Thanks. That was helpful.
God could put the variation in alleles in the right places obviously when He’s the one that made it work that way.
I’m just learning the senior or college-level biology I should learned or never took. I’m allowed to have an opinion. Generally I’m stubborn and opinionated about everything whether I know a lot about it or not.
I suppose I should just go read the referenced papers within the ones I linked and find the opposite view to learn more as well.
Anyone have a preferred resource about how humanity must have began as a large population?
Because there are only 5 people with descendants: Noah, his wife, and their kids’ three wives. The lowest possible frequency results from one of those people being heterozygous for the allele in question: 1 out of 10 haploid genomes.
That’s a huge number of miracles to add to the story. If you add enough miracles any data are compatible with any scenario. That way lies Last Thursdayism.
It’s all the same miracle of creation. Maybe we’re as diverse as is biologically possible. The God of the Bible likes diversity. He kept bringing foreigners into Israel and Jesus isn’t coming back until the gospel is preached to every nation, tribe, and tongue.
This vast increase in recombination frequency would have to continue for many generations after creation, so postulating that this could be addressed by designing the gametes with heterozygosity does not work.
, but that’s why I’m here - it helps me understand what I’m reading from them better if people point out their objections. Could you explain the problem further? I obviously can google meiosis.
