BTW, I object to the new title of this thread. I have clarified that my hypothesis does not specify God as the creator (though I admit I toyed with that idea early in the genesis of my idea). Please change the title to accurately reflect my position, if you will.
Your understanding is incorrect. This is not a tenet of GAE.
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Really? So according to GAE Adam and Eve could very well have no descendants living today?
Also, while I appreciate the change in the thread’s title, I am still not sure on what basis you claim the being in my hypothesis is “deceptive”. What deception do you see?
I suspect you have not quite grasped the difference between genealogical and genetic descent. Is that true?
You have already rearranged your scenario multiple times in order to make it undetectable. That isn’t deceptive? You have god creating 18% of the population in a way carefully arranged to make it appear as if they were the children of their putative parents. On the other hand, there is no such attempt in the case of A&E.
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If someone is my genealogical ancestor, that means if I follow my family tree up thru the generations, I will eventually come to that individual. This is not the same as genetic ancestry. In theory, we could determine my genealogical ancestors if we did not even know that genetics existed.
I will admit, I am a bit uncertain by what is meant by “genetic ancestry.” If we are referring here to coalescent theory, then this would involve tracing the lineage of a specific allele back until we identify the individual in which this allele first appeared by mutation. This individual, however, would not necessarily be the most recent common genealogical ancestor of the people who possess this allele.
Am I wrong about that?
Only if the being (not necessarily God) had said that all of the members of the human species are descended from the same ancestry, and none of them were ever, ever created de novo. When did he say that?
Otherwise, I fail to see who my scenario is any less deceptive than one in which God created a pair of humans who could quietly slip into the rest of the population and start mating with us without any sign that they did not come from the same ancestors as we did.
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No, it’s right as far as it goes. Do you realize it’s much easier for a past individual to be your genealogical ancestor than your genetic ancestor? That you have many more genealogical than genetic ancestors?
Not wrong so much as irrelevant. It’s not about mutations but about inheritance. A genetic ancestor contributed some portion of your genome. Most of your genealogical ancestors are not your genetic ancestors, and that’s the point here.
I reject your criterion for deception. He doesn’t have to say anything. He only has to make something look like something else.
Clearly, and I don’t know how to make you see.
Exactly. And, in GAE, God created an Adam and Eve who looked like they shared common ancestry with all the other humans on earth, when in fact they didn’t.
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Actually, I don’t. Please explain.
@swamidass There is something that I need clarified: In the theological framework in which GAE is supposed to operate, is it assumed that every human being now on earth was a descendant of Adam?
Are you familiar with the omphalos argument? One may distinguish between necessary appearance of age and unnecessary appearance of age. A&E would have been created as genetically human because they were intended to interbreed with other humans; necessary to the purpose. In your scenario, however, God engages in otherwise pointless acts to conceal the de novo creation of human zygotes.
You really should read some of Joshua’s posts on the subject, then. You don’t understand what you’re arguing against. Anyway, you inherit half your genome from each parent, a quarter from each grandparent, and so on, less and less each generation. But, aside from the parental inheritance, these are only averages, around which there is variance. On average, you get 1/128 of your genome from each of your 5-great grandparents. But that’s only an average. It’s likely that you get double that amount from one of them and none at all from another. The farther back in time, the less likely that you get any genetic material from a particular genealogical ancestor. The way it works out is that most people alive in 4000 BC are probably your genealogical ancestors, but only a few of them are your genetic ancestors.
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Yes, but a genealogical descendant, not a genetic descendant. Adam may have no genetic descendants at all. And almost everyone alive at that time would also be a genealogical ancestor of everyone alive today.
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OK, I got it.
Well, with all due respect (and don’t think I don’t realize how much is due), that is where I think you are wrong. The genomic evidence suggests that, thru all of human history, less than half of the human male population has had so much as a single descendant.
Single genetic descendant. You understand that every male who has only daughters leaves no Y-chromosome descendants, right?
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Yes, and I do not believe that is relevant. The relevant factor I am discussing is the odds that a male at a given time in the evolution of our species will die without having so much as a single genealogical descendant who will survive to reach sexual maturity. The paper I cited suggests that, over the history of our species as a whole, the odds of this are over 50%. Here is the author’s explanation:
In a nutshell, we examined the amount of genetic variability on the Y chromosome (which is inherited by males solely from fathers) and mitochondrial DNA (inherited in both sexes solely from the mother). According to population genetic theory, the amount of variation observed among any set of chromosomes surveyed in a population is proportional to two factors, the rate of mutation and the size of the population (in terms of numbers of reproducing individuals). If we factor out differences in the rate of mutation, then any leftover difference in the amount of variation between two samples of chromosomes should be due to differences in the sizes of the populations from which they are sampled. Applying this method, we were able to estimate the relative size of the female and male human populations (from mitochondrial and Y chromosome variation, respectively). We found that the breeding sex ratio is about two females per male.
On average (and over evolutionary time), any given human female has been more likely to reproduce than any given male. Said another way, males have had a higher variance in reproductive success than females. As a consequence, more different females have contributed to the modern gene pool than males. Rather spectacular examples of this phenomenon have been inferred from historical times using genetic data. Asian conquerors (such as Genghis Khan and Giocangga) and their male relatives appear to have made a vastly disproportionate contribution to modern Asian populations. Niall of the Nine Hostages seems to have had a similar effect on the gene pool of the British Isles. These types of events, where one person (or set of related individuals) experiences tremendous reproductive success, can have an effect on the gene pool that lasts for many generations. On the other side of the equation, we have to infer that there are many more males than females who do not successfully reproduce at all.
The female to male ratio, in terms of reproductive sucess based on the above data, is about 2:1. And since we know <100% of females will reproduce, that means the number of males who have reproduced is <50%. Maybe far less.
ttps://tierneylab.blogs.nytimes.com/2007/09/05/the-missing-men-in-your-family-tree/
No, it was relevant. Both mitochondrial and Y-chromosomal lineages can become extinct even when their possessors reproduce. It’s true that this doesn’t affect calculation of the ratios of male vs. female reproduction, but it does affect the absolute numbers. Further, mt and Y coalesce, but genealogical ancestry does not.
It may be true that >50% of males fail to leave offspring. But of those that did, 6000 years ago, everyone today is descended from almost all of them. Adam, supposing he existed, is not at all special in that regard, and there’s no need for a divine miracle to make it so.
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You misunderstand me completely. I did not claim that Adam being a common ancestor of all humans required a divine miracle nor that it would be exceptional in any way. I said that it was not guaranteed. And if God required that this be the case, then he could not have simply created Adam and Eve and then sent them off to join the rest of the population to fend for themselves. At the very least, it would require that God keep track of the human family tree, making sure the lines leading back to Adam never all reach dead ends, and intervening in whatever way needed to ensure this does not happen. This would require ongoing interventions on the part of God throughout human evolution in ways that have not been detected (and therefore, by your definition, were “deceptive”). Only once a point was reached when the entire population could be traced back to Adam could God kick up his feet and let things go on their own.
This does not appear to be an aspect of GAE that @swamidass has addressed, to my knowledge.
No one hear has yet been able to identify an important aspect of GAE that I have not understood. At the same time, no one has demonstrated a scientific flaw in my hypothesis and the criticisms leveled against it have largely resulted from failure to understand my claims.
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No, at the very least, it would require God to do nothing, as once Adam has reproduced at all, preservation of his genealogical lineage and its eventual spread to the entire population becomes the predominant likelihood, with no intervention. You are trying to create a need for intervention where none exists.
There is no scientific flaw, and that has nothing to do with the criticism of your hypothesis.
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