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Comment by sloreti | Hacker News Reader

"In more recent history, as a global average, about four or five women reproduced for every one man"

Correct me if I'm wrong, but isn't this the same as saying one man, on average, will father a child with about four or five different women? I suppose given the timescale being discussed, "recent history" may mean the last few centuries, but this average still sounds very high to me.

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You're... not right.

More like out of 5 men, on average only one would have any descendent whose genetic line survived until today. But he would have a lot.

Now, some of the other 4 might have had children, but they might have dies young, or in turn not have had any descendants whose genetic line is still around.

Of course, the same would have happened to women, so maybe out of 15 men and 15 women, 5 women and 1 man have genes that are still around.

Also note that, unless I misunderstand, this only applies to single gendered lineage. That is there must be an unbroken chain of male ancestors for the male genes, and female ancestors for the female genes. If one of the men without surviving male genes had 3 daughters who went on to have lots of kids, his genes wouldn't be seen in this data, even though his other genes are with us.

Having gone through that line of thought, I wonder if we're looking at some kind of "compound interest" effect here. I mean, if the male-only gene has 10% less chance to survive a generation, does it add up to much bigger and bigger numbers after hundreds of generations?

I'm not sure if that clarified much...

Yeah, it isn't clear what timescale they are discussing, but the graphic suggests that a near 1/1 pairing is a very recent phenomenon.

You still get at least an element of this with pretty recent til-death-do-us-part versions of serial monogamy: Gauss, for instance, had two wives, marrying a friend of his first wife after she died, and had children with both of them.

(I'd be surprised if serial monogamy alone were enough to get a 4:1 ratio, but you can definitely get > 1:1 ratios out of it.)

4 or 5 might be high, but it's still noticeable anecdotally (although more rigorous analysis would be interesting).

My ex-wife and I have no children, but her current fiancee has children with his ex-wife (who has no other children), and she and him plan to have children together. My dad has children with his ex-wife (who has no children with other men) and current wife, but my mom (his current wife) has no children with her ex-husband.

So in a very small anecdotal sample, men who have children may often have children with 2 (or more, presumably) women over a lifetime, even though at any given time, monogamy prevails.

Upon Googling, I think this comes from genetic analysis which suggests that people alive today have 4-5x as many female ancestors as male.

I don't know if this statistic is actually limited by "recent history" or not.

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