Testing Jeanson's Model: Y Chromosome Mutation Rates

In the Bible, the common ancestor is Noah, the father of 3 boys or men. So we don’t have to look farther for a common ancestor for men, only for women.

Yes, he does talk about that in the second video. He said his team almost stopped completely after they uncovered that fact, because they didn’t believe it either.

I’d have to check the video, I understood the graph to be only showing only adult males of a certain age in that time period. So the actual population would be many time larger.

Right, as I said, it would only track men of child-bearing age, if I’m understanding correctly.

Like I explained earlier, you can’t disprove evolution by believing in it.

This thread reminded me of a recent paper that I think might be of some interest here.

A community-maintained standard library of population genetic models

@swamidass I’m not sure if this is directly applicable to GAE, but might be fun to play around with a standardized set of demographic model simulations.
Also here is the git repo:

(feel free to split this off into its own thread as needed)

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Is that true of Young Earth Creationism too?

Why “almost”? Once your method is shown to be useless, you should stop. Period.

Not that many times. He’s fudging, and he’s misrepresenting the sources he claims to be using.

You are understanding Jeanson’s claim. Jeanson’s claim is wrong.

Coalescence theory isn’t about evolution, per se. It’s about how ancestry works. To state the problem very simply, Jeanson’s model doesn’t consider any men who have only daughters. Their Y-chromosome lineage drops out. In any population, some Y-chromosome lineages will disappear in every generation because of such men. Even in a population of constant size, that means that the Y-chromosome ancestry will narrow down as you go back in time, down to a single individual. But that single individual would have been only one man in a population of many millions of men, most of whom would have current descendants. But he’s the only man whose Y-chromosome descents don’t end at some point in daughters.

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Here is a simple diagram:

It’s about mtDNA, but works just as well for Y chromosome DNA if you swap the sexes.

Each row is a different generation, so the top row represents the first generation of this population, and the bottom row represents the 5th generation. As you can, this hypothetical population has a constant population size - there are 8 women (men) in each generation. The lines connect ancestors with descendants.

In the latest generation (bottom row), you can see that there are only women (men) coloured in black, indicating (along with the connecting lines) that they descended from the woman (man) coloured in black in the first generation (top row).

If we construct a phylogeny using the 8 modern-day (latest generation) women (men) and then apply Jeanson’s method to it (counting the number of branches through time), we would conclude that the population grew from 1 in the first generation, 2 in the second, 3 in the third, 5 in the fourth, and 8 in the fifth. But we know that the population size was constant, so Jeanson’s method leads to a completely incorrect conclusion and is therefore invalid.

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This digression is important but needs its own thread. Unfortunately that doesn’t seem possible. I’m tempted to close this thread and start another primed by the last video @thoughtful shared…

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Done. See here: Jeanson's Method of Inferring Past Population Sizes