

How Grandmas May Play Favorites - DanielBMarkham
http://www.newsweek.com/id/222472

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camccann
Okay, here's the fun bit: Having a nearby grandmother consistently increased
or _decreased_ a child's chances of surviving vs. not having a grandmother
around, in proportion to the expected number of shared X chromosomes.

From the article: _In other words, the effect of a grandmother perfectly
tracked the DNA. "The higher the X-relatedness," the scientists write in
Proceedings of the Royal Society B, "the more beneficial effect the
grandmother has on that child's" survival. That the correlation held across
four continents and four centuries suggests a biological, not cultural,
explanation._

Putting this in more specific personal terms, if you're male, _your mother has
a biological instinct to harm the future success of your sons_ , even if she
is not only unaware of it but aghast at the entire idea.

So, anyone still think that genes don't have much effect on behavior?

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ginkgo
The sex determining chromosomes are just two among 23 chromosome pairs in the
human genome.

All the number-play in the article is completely pointless.

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sorbus
The article addresses that, albeit very shortly: "It may seem arbitrary to
focus on X, one of 23 chromosomes, but it has 8 percent (1,529) of all our
genes, including some for fertility and intelligence, which affect
reproductive success."

Besides, it's one of the easiest things to see, and hence one of the easiest
to look at - and, as it's sex-linked, there is a very clear way to see its
effects (differentiating between paternal and maternal grandmothers, and their
effects on their grandchildren of either sex). All the other ones have exactly
a 25% chance to be transmitted to grandchildren, regardless of the path, and
are therefor even more useless to look at.

I must agree, though, that it would be nice if the article had included more
statistics about grandparents effects on the survival of children, and less
explaining their theories and math.

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freewheel
Link goes to Newsweek front page. Permalink for article?

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DanielBMarkham
Interesting -- that's not what I have here.

Link <http://www.newsweek.com/id/222472>

It includes the article id, which, at least on this machine, takes me to the
article.

Here's the print link which I should have used anyway:
<http://www.newsweek.com/id/222472/output/print> Maybe that will work better
for you

