Does Jeanson's model match "the population growth data from 1000 BC to the present"?

[thoughtful (Valerie (non-scientist))]

@Tim

What’s left is just yet another approximately exponential curve, that will have roughly the same shape as any other approximately exponential curve for the same time period – and so will be largely indistinguishable from them.

Um…This one looks different. Perhaps you’re talking about the last 900 years. If you think so, show how it does. I challenged Mays to this in YouTube comments also.

@John_Harshman

You most certainly do not get my point. The tree does not follow population growth. To suppose so is to entirely ignore coalescence.

How does it ignore coalescense? I’d like to understand that point.

Regarding what I was saying about drift earlier, I found the quote from you I was looking for (below). I understood you as saying that over time, y-chromosome drift will reduce male lineages over time so that there will be no branching. I’m only going a step further and saying, yes, exactly: with extreme drift and bottlenecks and branching every generation, branching we see in the resulting tree wasn’t eliminated because there was population growth.

“Further, given most reasonable assumptions, every strictly male lineage except one will eventually be eliminated because all it’s various branchings will end in daughters (or extinction, which is the same thing as far as Y chromosomes are concerned).”

New Jeanson Book: Traced Human DNA's Big Surprise

There’s your problem. Not every male passes on his Y chromosome. That only happens if he has sons. All the mutations that happen in males who have no sons are lost. Further, given most reasonable assumptions, every strictly male lineage except one will eventually be eliminated because all it’s various branchings will end in daughters (or extinction, which is the same thing as far as Y chromosomes are concerned). This is true whether the population is expanding, contracting, or stable. Then again, barring selection, that one remaining lineage will have experienced a number of substitutions per generation equal to the mutation rate per generation unless selection has been operating. And if there’s no selection, population size is irrelevant.