…which may explain certain things from my teen years:
We think we may have found the answer in a study entitled “Smart Teens Don’t Have Sex (or Kiss Much Either).” It’s one of those studies that isn’t that surprising on the surface, but the devil’s always in the details, isn’t it? Here are some highlights:
• Students with IQs above 100 and below 70 were significantly less likely to have had intercourse than those in between.
• Each additional point of IQ increased the odds of virginity by 2.7% for males and 1.7% for females.
• It’s not just home runs they’re talking about, either: a higher IQ decreased the likelihood of romantic contact in any sense, from holding hands to kissing, across the board.
• For males with IQs between 70-90 only 50.2% were virgin, whereas those with IQs above 110 were 70.3% virgins.
Sadly, there’s this, suggesting that the phenomenon isn’t restricted to teenage years:
Some insightful digging by blogger Half Sigma into the General Social Survey, which also includes an abbreviated intelligence test, has turned up a number of associations that speak to these theories. The relationship between sexual activity and intelligence found across adolescence and young adulthood appears to continue on into adulthood proper.
Not only do intelligent people have a delayed onset of sexual behavior, Half Sigma found that they also have a lower number of premarital sex partners throughout adulthood (18-39). While this is consistent with the above theory that high IQ people are more religious and conservative, this is, of course, not true. Religiousness correlates with lower IQ, and as HS shows in the same post, intelligent people were also more likely to say that premarital sex was not immoral. (Leaving those who did think it was immoral to participate in the bulk of it!) Most of the other theories are still consistent with this finding though.
Perhaps more revealing, HS, also showed that intelligence correlates with less sex within marriage for the same age range. While still consistent with pregnancy fears and competing interests, lower sex drive seems like a better fit. In fact another revealing finding from the Counterpoint survey was that while 95% of US men and 70% of women masturbate, this number is only 68% of men and 20% of women at MIT!
Also the idea that more intelligent people are too busy for the opposite sex not just in 7th grade to college, but throughout adulthood and for their own spouse, seems unrealistic. In fact the GSS also shows (PDF) that smarter people spend more time socializing with their friends, indicating their hours aren’t spent as uniquely isolated and narrowly channeled as the theory would require.
But lower sex drive and anxiety about sex’s consequences can’t be the whole story either. Half Sigma also showed that the smartest men in the GSS (approx. IQ >120) were also more likely to visit a prostitute. (Hardly indicative of cautiousness) This may suggest intelligent men are less able to find willing sex partners. Are smart men less attractive to women? Perhaps in some ways. For instance HS found that smart men were less likely to be athletic, and this paper shows, unathletic men and women have fewer sex partners. Athletic men, with more willing sexual partners are also less likely to visit a prostitute. Athletic activity gives men more masculine bodies, which are more attractive to women. A more masculine physique correlates with (PDF) an increased number of sex partners.
So intelligent people have lower libidos and less masculine physiques. What hormone is responsible for both sex drive and masculine builds? That’s right: testosterone.
And two new papers suggest that testosterone may depress IQ. One team found that salivary testosterone levels were lower for preadolescent boys with IQs above 130 and below 70. (the same two groups most likely to be virgins in adolescence)
Another paper suggests that a gene responsible for androgen sensitivity and higher sperm counts may also create a tradeoff for intelligence.
If any of this is true, I’m going to get a T-shirt that says "Outlier"
UPDATE: This T-shirt is pretty close.
UPDATE: Reactions from around the internets: