Y.E.C. Model: Was there rapid evolution and speciation post flood?

There seems to be a major point of disagreement amongst those proposing a Y.E.C. model of life's history. On the one hand, some propose wide spread and rapid evolution, including speciation (within "kinds") after the flood, while others deny that such things can happen. So, does the model require this speciation, especially considering that space on the Ark was limited? And how does it happen? Are beneficial mutations involved?Let's discuss the model, which seems to be in need of a major update.Anything relevant goes, including questions I like to ask like: how many giraffes were on the Ark and where did all the new Y-chromosomes come from?

Thread copied here from the Y.E.C. Model: Was there rapid evolution and speciation post flood? thread in the Proposed New Topics forum.

In order to get the species diversity we see today, creationists have proposed rapid evolution whereby in the years after the ark the limited species on the ark both spread worldwide and diversified into all extant species.The implications of this ad hoc rapid evolution idea are ridiculous. As I posted in Message 725 in the TRVE History of the Flood thread:

John Woodmorappe (a pseudonym for a high school teacher named Jan Peczkis), in his article titled The non-transitions in ‘human evolution’—on evolutionists’ terms, posted on the answersingenesis.org website, has argued this very thing. He writes:

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The relevant evidence clearly shows that Homo sapiens sensu lato is a separate and distinct entity from the other hominids. No overall evolutionary progression is to be found. Adam and Eve, and not the australopiths/habilines, are our actual ancestors. As pointed out by other creationists [e.g., Lubenow], Homo ergaster, Homo erectus, Homo heidelbergensis, and Homo neanderthalensis can best be understood as racial variants of modern man—all descended from Adam and Eve, and most likely arising after the separation of people groups after Babel.

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So Woodmorappe sees the change from modern man, i.e., Adam and Eve, to these four species of fossil man taking place since the Babel incident, which occurred after the global flood and in the range of 4,000 to 5,300 years ago.

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Homo ergaster is dated by scientists to between about 1.8 million and 1.3 million years ago, so the change from that critter to modern man took at least 1.1 million years. Now creationists propose a change from modern man to Homo ergaster in about 4,500 years (with instant fossilization and burial, along with a return to normal evolutionary rates). This post-Babel change from modern man to Homo ergaster would require a rate of evolution on the order of 250 times as rapid as scientists see for the change from Homo ergaster to modern man!

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Most creationists deny evolution occurs on this scale at all. Now creationists have not only proposed such a change themselves, but they see it operating 250 times faster and in reverse!

This illustrates the danger when creationists come up with an ad hoc explanation to get around one problem--the down-the-road implications produce even more problems to the point of total unworkability! That's certainly the case with the idea of rapid evolution.

Wow, a new thread, promoted instanteously, and very loosely worded, with no proofs of any statement declared by the Original poster.Amazing, I must learn that methodology.... in proposing and getting accepted.Edited by Davidjay, : No reason given.

One suggestion would be to address the information in the opening post instead of trying to change the subject of every thread to numerology. Another would be to address the arguments made by other people instead of twisting their words to mean the opposite of what they actually said. Once you show that you can stay on topic and debate honestly, then your threads will be promoted more quickly.

Why do the genetic samples from the time that Adam would have been alive correspond to genetic samples after the supposed flood?Why has some super genome never been found?

Just so we are all on the same page . . .By my count, if the entire human race is descended from Noah's sons and their wives then we could have a maximum of:1. Four alleles shared between the three sons, assuming that the four possible allleles (two paternal and two maternal) are found in at least one son.2. Six alleles between the three wives (i.e. two each).That makes for a total of 10 possible alleles for each gene. Do any YEC's want to argue against this count?Edited by Taq, : No reason given.Edited by Taq, : No reason given.

I've been accepting this notion that a lot of alleles per gene are necessary to explain all the diversity of people and animals from the ark, but recently it began occurring to me that this is unnecessary. I don't know where the notion came from, but isn't it true that genes have two and only two alleles? I think of the classical example of brown eyes versus blue eyes: the options are B or b and that's it. Each individual has a gene that combines those two possibilities and no others. A bb and a Bb (my own parents) will produce three brown eyed Bb's and one bb on average. A bb and a BB will produce all Bb's. Etc.I looked up a page on this subject in Morris and Parker's "What Is Creation Science? where Parker is discussing how all the skin colors of the human race are explainable from two genes, each with two and only two alleles. You get the entire range of darkest to lightest, with most in the mid-range, from only those two genes with their two alleles each. A, B, a, b and that's it.Supposedly some genes are observed to have many alleles in a population, though, and I spent some time trying to figure out how that could be the case if we started from two parents, Adam and Eve. What hit me recently is that genes have the two alleles, so that all those other alleles must be mutations that don't affect the function, the protein product or the phenotypic outcome. Then I kept thinking about Adam and Eve having four alleles until it finally dawned on me that a gene has TWO, and that's IT. (abe: Adam would have had two, B and b for eye color, and so would Eve. That would no doubt also have been the case for all their genes so that we can suppose that they had all mid-range traits even though their offspring could have the extremes of all the traits. /abe)From the example of the skin color range it's clear that some traits are governed by more than one gene, each gene having two forms or alleles. This is probably true of eye color as well as skin color but I'm not up on all that. But I finally came to the conclusion that this is all it takes to explain all the diversity we see in people and animals. So on the Ark there would have been two alleles per gene among all of them, but probably more genes than we have today for many traits but also in general overall.I've many times suggested that "junk DNA" is a record of formerly functioning genes that have lost their function due to the Fall, most of it probably through destructive mutations. I still think this very likely but since it is now being claimed that it isn't junk and actually has a function I guess I have to wait and see what is concluded about that.In any case the allele count is Two Per Gene. Period.Edited by Faith, : No reason given.Edited by Faith, : No reason given.

But there is no "Fall" in the Bible. That is another concept made up by the Apologists.In addition, all the genetic evidence from before the supposed "Fall" shows pretty much the same genetic types and after the supposed "Fall".Again, we see the same pattern of genetic evidence in critters from before and after the imaginary "Flood".

Restating the problem, assume that around 6500 years ago there were originally only two people, Adam and Eve.
Since each gene of a person can have at most two alleles, then Adam could have contributed at most two alleles for each gene, and the same for Eve.This means that the most number of alleles any gene could have for both Adam and Eve (the total human population in the beginning) and all their descendants is four, so the most number of alleles of any gene in the modern human population is also four.Since we know today through genetic analysis that some genes of the human population have more than four alleles then it must be true that there have been mutations in those genes, or that there were originally more than two people, or both that there have been mutations and there were originally more than two people.--Percy

Here's a modern YEC angle on rapid speciation within "kinds" after the flood from Answers in genesis

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Did Natural Selection Play a Role in Speciation?

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How Species Arose after the Ark

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by Dr. Nathaniel T. Jeanson on July 30, 2016

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In our series, we’ve concluded that many new species have formed from the kinds that Noah took on board the Ark. We also observed that, when God created the kinds, He frontloaded them with genetic differenceswith the potential to form all sorts of new species and varieties.

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This fact alone completely transforms Charles Darwin’s mystery of mysteriesthe origin of species.1 Darwin had no concept of our understanding of modern genetics, and the conclusions we have reached were entirely inaccessible to him. Specifically, with respect to how species change and the ultimate source of the visible varieties we observe, Darwin had no genetic insights. Conversely, since species are defined by their heritable traits, our modern genetic discoveries represent the first real, comprehensive answer to the central question Darwin pursued.

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Our previous post left one significant detail unaddressed. While we carefully elucidated the origin of the vast majority of genetic varieties observable today, we didn’t quite connect the dots to how these varieties in individuals become distinct populations of new species.

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From Genetic Differences to Visible Differences
In prior posts, we argued that, in individual members of the various kinds, God created the two copies of DNA different from one another. In technical terms, this is referred to as being heterozygous. For new visible traits to arise from this created heterozygosity, all that appears to be required is a shift from heterozygosity to homozygosity. The prefix homo- denotes same, and a movement towards homozygosity is a change from a DNA state in which the two copies differ toward a DNA state in which the two copies are more and more similar to each other.

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To clarify, a shift from heterozygosity to homozygosity does not necessarily involve every chromosome. Though the image below depicts the most extreme examples (e.g., completely heterozygous and completely homozygous), a partially homozygous/partially heterozygous state can also exist. For example, if some of the chromosome pairs end up identical while other pairs remain different, this would represent a partially homozygous/partially heterozygous state. In fact, homozygosity need not even be at the whole chromosome level. Tiny chunks of a chromosome pair can be homozygous while other sections are heterozygous. Thus, a shift from heterozygosity to homozygosity can happen over a broad range of chromosome pairs and at multiple levels of chromosome organization.

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Click to enlarge

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Human DNA is inherited from both parents. Hence, the condensed forms of DNA (visible in the top part of this image as floppy, noodle-like structures called chromosomes) come in pairsone of each pair is inherited from each parent. Because our parents are different, each member of a chromosome pair is different from the other, as under scenario #1 on the left part of this image. Since Adam and Eve were created directly by God without human parents, it’s possible that both members of each chromosome pair were created identical, as in scenario #2 on the right. Nonetheless, available evidence suggests that each member of a chromosome pair was created different from the other. Under this scenario, it’s very easy to explain the millions of DNA differences that exist among humans today.

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Producing a more homozygous state is not hard. Gregor Mendel’s experiments with pea plants are instructive in this respect. At the visible level, Mendel observed that some traits can be hidden in one generation and appear in the next. For example, two pea plants that produce green, smooth-shaped pea pods can be crossed, and their offspring are a mix of 1) green and smooth-shaped pea pods, 2) green and rough-shaped pea pods, 3) yellow and smooth-shaped pea pods, and 4) yellow and rough-shaped pea pods. The information for yellow pea pods and rough-shaped pea pods was present in the parents, but it was masked. Green and smooth were dominant over yellow and rough.

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Though Mendel was unaware, we now understand this phenomenon in more specific DNA terms. Since DNA is present in two copies (e.g., in chromosome pairs), even in pea plants, we can infer the DNA makeup of the green, smooth-shaped parental pea plants that gave rise to the same, as well as to yellow or rough-shaped pea pods. In short, for yellow or rough-shaped pea pods to appear consistently in the offspring of green and smooth-shaped pea pod parents, both parents must be heterozygous for the information for pea pod color and shape. In other words, in one pair of chromosomes, one copy of DNA in the parent must specify yellow and the other must specify green. Similarly, in another pair of chromosomes, one copy of DNA in the parent must specify rough and the other must specify smooth. When this heterozygous state exists, only green and smooth-shaped appearthey are dominant over yellow and rough-shaped.

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In the process of crossing the pea plants, only one copy of the each DNA pair is passed on from parents to offspring. If one or both of the copies carries the information for green pea pods, then offspring will have green pea pods. However, if the copy from one parent contains the instructions for yellow pea pods, and if the copy from the other parent also contains the instruction for yellow pea pods, the DNA information in the offspring will be only yellow. Since no information for green is present, the information for yellow is no longer hidden or masked by the dominance of the information for green pea pods. Hence, when two heterozygous parents are crossed, visible changes in traits can appear in a single generation.

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FOR A NEW SPECIES TO FORM, IN TECHNICAL TERMS, HOMOZYGOSITY MUST BE MAINTAINED.

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For this process to lead to the formation of a new species, a new population must be formed. If a new population does not form, the yellow offspring might cross with green offspring, and the next generation will have the yellow trait hidden again. Under this scenario, no permanent change will have taken place. For a new species to form, in technical terms, homozygosity must be maintained.

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How could a homozygous state be isolated and kept from being mixed with heterozygous individuals? How could yellow pea pod offspring be prevented from crossing with green pea pod individuals?

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In Gregor Mendel’s case, he personally oversaw the breeding process. Similarly, in animals, human breeders keep desired offspring from mating with other individuals that lack the desired traits.

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But in the wild, no human breeders exist. How could homozygosity be maintained?

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Unlike plants, animals can move or migrate. Homozygous animal individuals can easily be isolated from heterozygous individuals by migration. Not surprisingly, many species today are geographically isolated from one another.

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For example, as their names imply, the African and Asian elephants exist on different continents. As another example, the 7 wild species of horse-like creatures that exist todayincluding three different species of zebrasare spread out over Africa and Asia. In the cat family, tigers are Asian, lions are primarily African, jaguars and pumas are American. In short, on a globe as big as ours, geographic isolation is easy.

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Notice that we haven’t discussed survival of the fittest. For homozygous individuals to be isolated away from heterozygous individuals, the death of the original heterozygous individuals is not required. Migration of homozygous groups away from heterozygous groups would do the job just fine.

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Naturally and by chance, some individuals will die, and others will survive to reproduce.4 As we observed in a previous post, the vast majority of mammal kinds died permanentlythey’re extinct. But repeated cycles of massive population death followed by survival of a few individuals to found a new population are not necessary for speciation. Once God created kinds with enormous genetic variety from the start, reproduction and migration were virtually all that were needed to produce a huge number of species.

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Speciation from Start to Finish

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WHEN GOD CREATED THE KINDS HETEROZYGOUS, HE VIRTUALLY GUARANTEED THE FORMATION OF NEW SPECIES.

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Let’s put the pieces together one more time to understand how easily species formed post-Flood. When God created the kinds heterozygous, He virtually guaranteed the formation of new species. The statistics of reproduction ensure the appearance of new traits in one or a few generations, and simple population growth curves indicate that these offspring can found new populations in short order. As these populations moved away from one another geographically, new species could form.

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Is this process still occurring today? Take the African Cape buffalo as an example. Its curved horns have become a symbol of African wildlife. Yet several subspecies of the Cape buffalo exist. These subspecies also happen to be geographically distributed across the African continent. In perhaps a few decades, it wouldn’t be surprising if scientists labeled these subspecies as separate species.

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If this occurs, most people in the professional scientific community would probably view this as simply a bookkeeping change. Yet the process of speciation that I outlined above suggests that, in fact, what we’re observing right now is a bona fide formation of a new species.

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Subspecies exist in many other species.6 Hence, speciation could be happening right now all over the planet. If we’re willing to consider the biblically consistent, scientifically justified model that I outlined above, I think we’d see a complete replacement for Darwin’s answer.

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To underscore this fact, it should be clear from all that we’ve discussed that young-earth creationists are not evolutionists. We’re not a spin-off or an odd extension of Darwin’s principles. Instead, we postulate a very different source for the genetic variety we see today, and we explain speciation on a very different timescale.

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UNDER THE PARAMETERS WE JUST LAID OUT, EVOLUTION AS DARWIN DESCRIBED IS NOT POSSIBLE.

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Furthermore, this front-loading of genetic information at the creation event also naturally sets limits on the speciation process. Since most of the genetic variety we see today goes back to the Creation Week, formation of new kinds (i.e., higher categorizations, such as at the Family level, not species) would require a massivemiraculousinput of new genetic information. Under the parameters we just laid out, evolution as Darwin described is not possible. In contrast, formation of new species from the kinds on board is not only possible, it represents a scientifically superior explanation to any that Darwin or his scientific descendants have proposed to date.

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So, any thoughts? AiG seem to have given up the traditional species immutability in favour of massive rapid speciation within kinds.Some YECs seem to disagree, and there are other models. I'll be adding links to YEC views as the thread goes on.The model described above does make predictions, and would seem to create as many problems in relation to genetics as it solves (if not more).It seems to be a reaction to modern genetic kinowledge, and perhaps to the realisation that the Ark would have been very crowded if there was no subsequent speciation.

More to the point, if there are hundreds or even thousands of alleles for a single gene, would this require rapid evolution starting with the survivors of the ark, or as Percy states, starting with the two people who founded the human species? Why couldn't there be more than two alleles, and why couldn't they all differ in function? How did you determine that all skin color related genes only have two alleles? 90% of the human genome is still considered junk when junk DNA is defined as DNA sequence which has no significant impact on fitness. We can determine it is junk because of the rate at which it accumulates mutations. Pseudogenes make up a small proportion of junk DNA.

One or two alleles for most, but some genes can have 100 or more, especially in immune systems. I've forgotten what the known record is in humans, but I'll look it up for you.Adam and Eve would have had four, just 300 generations ago. That sounds like a dramatic increase in information to me!

Sounds like you didn't read my whole post since I deal with that claim about genes having more than two alleles, so it needs to be answered. As I said in my post, after giving the Bb example of a typical gene with two alleles, I suspect all those extra alleles people talk about are the result of mutations that don't change the function of the gene. Have you evidence of 100 different phenotypes from those 100 alleles in immune systems?How about a mere four? If you can't show actual phenotypic differences between those four then the best explanation is that two of them are normal built-in alleles that do specific identifiable things like produce blue eyes or brown eyes, and the others don't do anything different, making them "neutral" mutations. Edited by Faith, : No reason given.

Human blood types come to mind. That's actually three alleles producing four phenotypes and six genotypes. And I'm pretty sure that there will be lots differences in phenotype in the immune system, as it depends on these variations.More to the point, what makes you think humans can have all these variants, regardless of function, when there were a maximum of four 300 generations ago? Are you proposing a super high and probably lethal mutation rate?