Today’s Friday Weird Science comes to us courtesy of ProfLike Substance, who passed on this truly GLORIOUS paper to Sci many weeks ago. I’ve been dying to blog it for ages, but other things (like whale penises) seemed to always come up (you see what I did there) and required immediate blogging before someone else got to it. But finally, FINALLY I get to sit down with what may be the most adorable paper, from the weirdest laboratory ever.

So men, have you ever really THOUGHT about your pants choices and the effect they could have on your sperm? Boxes vs briefs? Wool vs denim vs polyester? Why haven’t you!??! Cause this guy has.

Behold: rats wearing pants.

Shafik. “Effects of different types of textiles on sexual activity” European Urology, 1993.


From the actual paper! How cute is that?!!?

The work in this study is based on previous work in humans and in dogs (which Jason and I both covered in one very EPIC day on blogs and twitter. Hehe, recepticle for your testicle…hehehehe… why haven’t these guys won the IgNobel yet?!) showing that the wearing of polyester underpants caused a decrease in sperm count down to almost zero after a continuous wearing of 5 months in humans. Cotton underpants had no effect. The authors thought that electrostatic potentials from the polyester were to blame, and this author claims that the potential temperature effect was minimized due to features of design. From my reading of the paper, I didn’t get that at all, and in fact there was a significant temperature increase. Oh well.

Anyway, much as humans are unlikely to be wearing pure polyester underpants, they do wear blends, and some guys do like to go commando. And so this guy undertook a massive study, using 75 rats, a lot of cotton and polyester, and a very tiny little sewing machine, to see what effect different types of pants might have on sexual behavior in rats.

Really, I’ve got to wonder why we didn’t just go straight to humans here, and look at libido changes with continuous wear of different kinds of underpants. Possibly because it’s hard enough to get volunteers for that kind of study without asking them how horny they are…

I’ve got to think that this guy’s lab must be the CUTEST lab EVER. You’d need a washing machine for the pants. Little sewing machines for the rat pants. Maybe a little closet full of little rat pants! The possibilities are endless. Also kind of gross. I can only imagine what those rat pants looked like at the end of the day…

So he took 75 rats and divided them into five groups. One group hung proud and free. The second group got pure polyester pants (hopefully in a variety of delightful paisley patterns). The third group got a 50/50 blend of polyester and cotton, the fourth got cotton, and the fifth, long-suffering group of rats got 100{9f43b4361d9a125bc126dd2a2d1949be02545ec69880430bc4fed2272fd72da3} wool. The rats wore the pants for 6-12 months

The pants had openings for the penis, butt, and tail, but I have to wonder how effective those were. I mean, the pants GOTTA stay on, so they need to be kind of tight. But then, I imagine the penis and anus holes didn’t work very well. I imagine this author had to wash a LOT of little pants.

After 6 and 12 months, the rats were put with ladies, and tested for their sexual behavior. What we’re looking for is changes in intromission and mounting. They were also rated as “potent” if the males got an erection and entered the female, and “impotant” if they got on the lady, but couldn’t get it up.

And of course the data is ALL in tables. Look what I do for you. I graph because I love.


(Edit: The stuff had to be regraphed because I was tired and screwed up the figure legends. These are the correct ones. I think. I’m only a little less tired now.)

You can see that the number of mounts (times the rats intended to get it on), and intromissions (when they succeeded). The polyester and cotton polyester blends had the biggest effect, with a real decrease in sexual behavior, while the cotton, wool, and commando groups did just fine. The mounts increased (oh those poor boys are trying!), but the intromissions decreased (FAIL).

The author also looked at the electrostatic potentials, and noted that there weren’t any produced in the wool, cotton, or commando groups, but that the polyester and cotton/polyester blend groups both had significant electrostatic potential. The author hypothesizes that the electrostatic potentials themselves were communicating through the skin into the corpus callosum of the penis, and causing the rats to exhibit erectile dysfunction.

Sci’s not so sure about this. IS it the electrostatic potential? What about heat? And what about the severe embarrassment of wearing polyester pants? Also yes, there was a decrease in sexual activity, but they didn’t look at any potential decreases in sperm count or sperm motility, nor did they take the temperature of the rat’s balls to see if they were higher than normal. So sexual behavior is down, but is heat up? And what about the sperm count (I think it’d be down, but I’d like to see). Is there a way to create an electrostatic potential like this WITHOUT heating the balls, to see if the decrease in sperm count is actually due to the heat? And is there a way to do this without creating some very uncomfortable rats?

Because hey, maybe the rats were just SERIOUSLY UNCOMFORTABLE. After all, they were wearing POLYESTER PANTS continuously for a year!! Can a rat get a kilt or something?


(Source)

Maybe electrostatic potentials are themselves uncomfortable?

So who knows whether the net result should be a worldwide ban on polyester underpants, and whether electrostatic potentials are making these rats go limp.

Shafik A (1993). Effect of different types of textile fabric on spermatogenesis: an experimental study. Urological research, 21 (5), 367-70 PMID: 8279095