

Quality of a man’s sperm depends on how intelligent he is, and vice versa (2008) - pwrfid
http://www.economist.com/node/12719355

======
mkl
The correlation is quite small, but interesting nevertheless. I tried looking
for replication studies, but couldn't find any.

Here is the publication in question:
[http://www.udel.edu/educ/gottfredson/reprints/2009semen.pdf](http://www.udel.edu/educ/gottfredson/reprints/2009semen.pdf)

Here is an addendum trying to explain why it might be the case:
[https://www.ncbi.nlm.nih.gov/pmc/articles/PMC2775227/](https://www.ncbi.nlm.nih.gov/pmc/articles/PMC2775227/)

------
dtech
To get behind the paywall, simply Google the title.

I still don't get how Google doesn't nuke the websites that do this into
oblivion...

~~~
ivank
Google's users don't see the paywall, so why would Google care?

~~~
davej
Because google claims to care about the wider web not just its search product.
This breaks the web.

~~~
judk
"Paywalls break the web" is a rather strong claim.

~~~
WorldWideWayne
Well consider this - A google user finds a link, doesn't realize there is a
paywall and shares the link with the rest of the web. Now the rest of the web
has to go through google to get to the link. That sounds broken to me.

~~~
sxtxixtxcxh
sounds like it works out in google's favor though...

------
IgorPartola
Alternative theory: men think with their junk. OK, I'll see myself out...

In all seriousness, it'd be great to see a more thorough study here. I see so
many confounding factors. Measuring intelligence is a tough one. Perhaps
people more likely to score higher on intelligence tests come from a part of
the world where higher sperm counts were selected for genetically. For
example, how do sperm counts correlated with the number of cold vs hot days
during an average year? Or humidity levels? Or circumcision traditions? Or
average penis size? My point is that there are so many factors that go into
calculating intelligence and at least to me it seems there are as many factors
that affect sperm count that this correlation may be influenced by several
other hidden variables.

------
mkesper
If this would be true, we'd already live here:
[https://en.wikipedia.org/wiki/Idiocracy](https://en.wikipedia.org/wiki/Idiocracy)

~~~
luxpir
Doesn't the standard IQ (I know, I know) bell-curve indicate that the majority
of humans are less intelligent than the most intelligent? [1]

I suppose the question is how much less intelligent does the majority have to
be for the world to look like Idiocracy? How likely is that to happen, given
the communication tech and education options that are emerging?

EDIT: [1] Fair point, riffraff. Actually quite tough for me to rephrase
without spending significant time on it (I'm clearly not in the minority...),
how about: "the most intelligent humans (by IQ) are naturally in the minority,
as with any natural distribution/bell-curve, meaning the 'less intelligent'
majority already dominate, as in Idiocracy, and by definition they must always
continue to do so". That's a mouthful, but I hope the point is clear enough.

~~~
riffraff
I think you should rephrase your first line, as it would seem to me the
majority of anything is always less anything than the top. (i.e. half of the
people are of below average intelligence)

~~~
judk
In a constant distribution, the majority equals the max.

Some phenomena ate approximately constant. (How many eyes do you have?)

------
lmg643
my understanding is that transmitting intelligence to the next generation
requires (a) the presence of whatever genes are responsible for intelligence
and (b) the absence of mutations affecting those genes.

it would make sense that the quality of sperm correlates with intelligence,
because it would have to be less damaged in order to reliably transmit these
attributes. the headline seems to dance around this, perhaps because of the
controversy involved.

one unfortunate factor which affects the quality of sperm - paternal age.
average number of mutations increase every year. so if you're "thinking" about
starting a family, consider that a disincentive to wait.

------
cm2012
"They may, for example, be less likely to smoke, more likely to eat healthy
foods or to exercise, and so on." I would chalk up the small correlation
documented to this. Higher IQ people tend to be higher on the social scale and
be healthier in a large variety of ways.

~~~
a8da6b0c91d
Why would you make that assumption? IQ and sperm quality are probably both
impacted by deleterious mutations. I would assume quality in both is measuring
mutational load way before I made suppositions about SES.

------
Houshalter
This is very significant. If human _general_ intelligence was just a
coincidence of runaway sexual selection, then what are the chances of that
occurring again on a different planet? How many times have peacocks
independently evolved?

------
PedroBatista
So i can't still figure it out..

Smart guy --> better sperm or Better sperm --> smart guy

maybe my sperm is telling me something with this question.

------
mantrax5
"Quality of a man’s sperm depends on how intelligent he is, and vice versa"

I don't think people know what "depends" means anymore. Especially the "vice
versa" part.

That means if you improve the quality of your sperm, as a direct consequence
you _will_ become more intelligent, which brings forward all kinds of
interesting questions, such as do men _really_ think with their balls?

~~~
Machow
Agreed. That title made wonder what kind of crazy set of working memory
training experiments took place. And I don't even know how they would test
things in the other direction...

