There's a scientifically interesting and delightfully anti-arousing article over at Scientific American with an overview of why human penises are how they are. Even if you think evolutionary psychology is a load of arm chair philosophizing bunk (which it sometimes is), you can at least extract some immature giggles from this one. And honestly, he does a decent job at pointing out some of the drawbacks and limitations of evo psych. But wait, these researchers actually did an experiment on the "semen displacement hypothesis" instead of just sitting around and thinking!
"The researchers selected several sets of prosthetic genitals from erotic novelty stores, including a realistic latex vagina sold as a masturbation pal for lonely straight men and tied off at one end to prevent leakage, and three artificial phalluses. The first latex phallus was 6.1 inches long and 1.3 inches in diameter with a coronal ridge extending approximately .20 inches from the shaft. The second phallus was the same length, but its coronal ridge extended only .12 inches from the shaft. Finally, the third phallus matched the other two in length, but lacked a coronal ridge entirely. In other words, whereas the first two phalluses closely resembled an actual human penis, varying only in the coronal ridge properties, the third (the control phallus) was the bland and headless horseman of the bunch.""Hey honey, how is grad school going? Research okay?" "Uh...yeah, it's great, Mom." "Do anything interesting today? What exactly are you studying again?" "Um...human...behavior. Yeah." "That's nice sweetie. So when you're a doctor you can write us prescriptions, right?" "...I'm not going to be that kind of doctor, Mom."
And then he proceeds to jump off a bridge.
Anyway, it gets better:
"Next, the authors borrowed a recipe for simulated semen from another evolutionary psychologist, Todd Shackleford from Florida Atlantic University, and created several batches of seminal fluid. The recipe “consisted of .08 cups of sifted, white, unbleached flour mixed with 1.06 cups of water. This mixture was brought to a boil, simmered for 15 minutes while being stirred, and allowed to cool.”"What did I learn during my PhD? How to make fake semen! Comes in handy more often than you'd think!
"In a controlled series of “displacement trials,” the vagina was then loaded with semen, the phalluses were inserted at varying depths (to simulate thrusting) and removed, whereupon the latex orifice was examined to determine how much semen had been displaced from it. As predicted, the two phalluses with the coronal ridges displaced significantly more semen from the vagina (each removed 91 percent) than the “headless” control (35.3 percent). Additionally, the further that the phalluses were inserted—that is to say, the deeper the thrust—the more semen was displaced. When the phallus with the more impressive coronal ridge was inserted three fourths of the way into the vagina, it removed only a third of the semen, whereas it removed nearly all of the semen when inserted completely. Shallow thrusting, simulated by the researchers inserting the artificial phallus halfway or less into the artificial vagina, failed to displace any semen at all. So if you want advice that’ll give you a leg up in the evolutionary arms race, don’t go West, young man—go deep."Indeed, sir. Indeed.
Seriously, the idea of a bunch of grad students pumping together two sex toys filled with flour semen paste is the most ridiculous image in my mind. There's no way any human being could have done this with a straight face. I would like to see a psychological study on just how fucking awkward and hilarious that situation must have been.
I'm not sure if I would be overjoyed or mortified if my job as a grad student was to pick out suitable sex toys and then see which scoop out fake semen best. It would sure make a good bar story, at least. I'd have all the guys.