Of Balls and Brains...

[dmp]

Who woulda thought?

Animal behaviour

Bats and balls
Dec 8th 2005
From The Economist print edition

Bigger testes mean smaller brains


MEN are often accused by women of, to put it bluntly, having their brains in their balls. A joke, of course. But perhaps not as much of one as people might like to think. For a study of bats carried out by Scott Pitnick, of Syracuse University in New York State, and his colleagues, suggests that there really is a trade-off between the two organs.

With about 1,000 species, bats are the second-largest group of mammals (rodents are top), so there is plenty of material for interspecies studies. Dr Pitnick's project, published in this week's Proceedings of the Royal Society, looked at brain size and testis size in 334 of those species. Sadly, the team's research budget did not allow it to jet around the world and gather data directly. Instead of visiting bat caves, the scientists visited their universities' libraries. But bats are a well-studied group, and so the team was able to gather pertinent data on the anatomy and behaviour of a third of them.

The hypothesis they were testing came in two parts. The first was that in any given species, the average male's testis size as a fraction of body weight will depend on the behaviour of that species' females—in particular, how promiscuous those females are. The second was that, given that brain tissue and testis tissue are among the most expensive to maintain physiologically, and that bats have a very tight energy budget, bigger balls would result in smaller brains.

The team knew, from work done some time ago, that the first part of their hypothesis is true in primates. Greater promiscuity in females does, indeed, lead to bigger testes, presumably because a male needs to make more sperm to have a fighting chance of fathering offspring, if those sperm are competing with sperm from a lot of other males. Gorillas, which discourage dalliances between other males and the females of their harem, have small testes. Chimpanzees, among whom females mate widely, have large ones. Human testes lie between these two extremes.

And so it proved in bats. Bat testes range from 0.11% of body weight in the African yellow-winged bat, to a whacking 8.4% in the generously endowed Rafinesque's big-eared [sic] bat. (The largest primate testes by contrast, those of the crab-eating macaque, are a mere 0.75% of body mass.) And the small balls were indeed found in species where females were monogamous (though they might be members of harems), while the large ones were found in species where females mated widely.

Brain size, by contrast, and just as predicted, varied in the opposite direction. Nor was it dependent on the level of male promiscuity. In the bat world, it seems that you do not have to be cleverer to be a libertine than to be a faithful husband. But if the girls are putting it about, it is better to be virile and dim, than impotent and smart.

http://www.economist.com/science/displayStory.cfm?story_id=5278157

That last line is Signature Material.

 

[theHawk]

lol good stuff

 

[Nienna]

Aren't there ANY who are both virile and smart?

 

[Avatar4321]

Aren't there ANY who are both virile and smart?

Sure. if women didnt sleep around so much with us we would all be smart, but if we were in monogomous relationships we'd still be virile.

 

[dmp]

Aren't there ANY who are both virile and smart?

I've got two kids, and am no dummy...

More wisdom than intelligence though...

how YOU doin'?

 

[Abbey Normal]

...to a whacking 8.4% in the generously endowed Rafinesque's big-eared [sic] bat.

So, there is a correlation between big ears and... :teeth:

 

[Said1]

So, there is a correlation between big ears and... :teeth:

I thought the distance between thumb and index finger was relative, or was that foot size?

 

[deaddude]

There is no correlation between brain size and intellegence. For instance men tend to have larger brains then women, even women who are demonsrably smarter, because in general men are larger than women and so have preportionaly larger brains.

Additionally certain activities such as juggleing can increase the size of certain areas of the brain.

of (juggling) balls and brains

Ha mines bigger than yours hahahahaha

 

[William Joyce]

There is no correlation between brain size and intellegence.

But there is, and the evidence is overwhelming:

http://www.eugenics.net/papers/rushton.html

 

[deaddude]

Yes WJ eugencis is right, and so is prenology, and ether theory. Any other long debunked theories that you would like to back?

 

[Psychoblues]

Typical obsession within the right wing nut crowd. Speak on you enlightened few.

I wear a size 11 shoe and I'm only 5'10". Go figure?

Pitiful, or maybe sickly humorous is all I can say for your analogies thusfar professed.

Psychoblues

 

[rtwngAvngr]

Aren't there ANY who are both virile and smart?

You rang?

 

[manu1959]

Typical obsession within the right wing nut crowd. Speak on you enlightened few.

I wear a size 11 shoe and I'm only 5'10". Go figure?

Pitiful, or maybe sickly humorous is all I can say for your analogies thusfar professed.

Psychoblues

you are the only one throwin out numbers.....short dude with flipper feet.....napolean complex....explains all your posts

 

[Gunny]

you are the only one throwin out numbers.....short dude with flipper feet.....napolean complex....explains all your posts

LMAO ..... I have coffee to clean off the screen now ..... :cof:

 

[Annie]

LMAO ..... I have coffee to clean off the screen now ..... :cof:

I did try to rep, but gotta spread it around first.
:rotflmao: :rotflmao: :rotflmao:

 

[Gunny]

I did try to rep, but gotta spread it around first.
:rotflmao: :rotflmao: :rotflmao:

Hell, I repped him. "short dude with flipper feet" is a classic.

 

[manu1959]

thank you,....i will be here all week

 

[Gunny]

thank you,....i will be here all week

Yeah, but your boy won't. Apparently he can only sneak on late night weekends.

 

[007]

Yeah, but your boy won't. Apparently he can only sneak on late night weekends.

Thank God for small favors. That's about all I can take of him.

Short with big feet... hmmm. Wonder if he's got red hair? HEY, he's RONALD McDONALD!

 

[Abbey Normal]

You rang?

Beautiful response!