Another week brings another bunch of discoveries about sex. This week brings us break-throughs on the origin of the human penis. But don’t worry—we also bring you some penis-related news about sexual fantasies, porn addiction and the health benefits for men of having sex with more than 20 women.
1. Men finally have a cancer-based justification for sleeping with lots of women.
Good news, straight men! You no longer have to face societal shame and scorn for sleeping around—oh right. You don’t. That’s women. Sorry. Let’s try again. Good news, men! You are now even more sanctioned to sleep around with multiple women. A study from the University of Montreal has found that men who have slept with more than 20 women have a 28% lower risk of prostate cancer than men who have slept with only one woman. And male virgins have twice as much risk of prostate cancer as men who have had sex with many women. Unfortunately, gay men who want to justify having multiple partners (it’s not for me, it’s for my prostate) are out of luck. It turns out that among men who have sex with other men, there is an inverse relationship: those who have had sex with more than 20 people are twice as likely to get prostate cancer as men who have never slept with a man.
2. Penises! They’re just like limbs! Or tails!
Have you ever wondered why male mammals have one penis while snakes have two? A new study from Harvard Medical School's Department of Genetics found that reptile genitalia come from the tissue that creates hind legs, so there are two penises, just like there would have been two legs, before they evolved. In mammals, the genitalia come from a tail bud, so there is one penis.
3. The origins of the penis.
So how are these limb-based or tail-based genitals formed? It turns out the embryonic cloaca, which turns into the reproductive, urinary and gut tracts, sends molecular signals to nearby cells to form external genitalia. So, the location of the cloaca is what determines where the penis develops. The Harvard researchers tested this theory of cloaca importance by grafting cloaca tissue next to the limb buds in one group of chicken embryos and next to the tail buds in another group. Genitals developed close to the limb buds in the first group and close to the tail buds in the second. As the lead author of the study, Patrick Tschopp, told BBC, "by misplacing a molecular signal you can misguide these cells in their developmental trajectory.” Exactly. That’s what I just said.
4. Your sexual fantasies are probably pretty normal.
A new study from the Université du Québec and the Philippe-Pinel Institute of Montreal published in the Journal of Sexual Medicine looks at sexual fantasies and discovers, shockingly, that they are not that rare. The researchers asked 1,516 participants to rate 55 sexual fantasies and write down any fantasies they had they weren’t among the 55. The study found two fantasies to be “statistically rare” (shared by 2.3 percent or fewer of participants): having sex with a child under age 12, and having sex with an animal. (Just a reminder, both of these are illegal in real life.)
Nine of the fantasies were “statistically unusual” (shared by 15.9 percent or less of participants) and included “urinating on partner,” “being urinated on by partner” and “wearing clothing associated with the opposite sex.” “Statistically common” fantasies (shared more than 50 percent) included, “Having sex with someone that I know who is not my spouse,” “Masturbating my partner” and “Being masturbated by my partner.” Three fantasies were “statistically typical” (shared by more than 84.1%): “feeling romantic emotions during a sexual relationship," "fantasies in which atmosphere and location are important" and "fantasies involving a romantic location." Yeah. Those are pretty vanilla.
Interestingly, though 85.1 per cent of the participants identified as heterosexual, 3.6 per cent identified as homosexual and the remainder identified as neither, the percentage of the participants who had “homosexual fantasies” was much larger than the 11.3% who did not identify as heterosexual. 36.9% of women, for instance, fantasized about having sex with two women, 35.7% of women fantasized about performing cunnilingus, 26.8% of men fantasized about performing fellatio, and 45.2% of men fantasized about having sex with two men.