From Steve Horwitz, via email.
A new article in Biology Letters reports on a British twin study which estimates that 34% of the ability of females to have orgam during intercourse is genetic (confidence interval 27–40%). The number goes up to 45% for orgasm in masturbation (confidence interval 38–52%). The study sent questionnaires to members of the British national twin registry. They received replies from 683 non-identical twins and 714 identical twins.
This follows an earlier Australian study which I am trying to track down. It would help if I could get the Biology Letters article.
So how does this bear on the Symmons evolutionary hypothesis that we have been discussing on this blog? If the female orgasm is a developmental byproduct of the male orgasm, we should expect genes associated with female orgasm to show a lot of variation. If there was direct selective pressure on the genes, that should show up as reduced genetic variability.
Here is the write up from SFGate.
This is the write up in New Scientist.
Note some of the discrepencies in science journalism. New Scientist says this is the first study of this kind. SFGate points to the Australian study earlier this year. Also, New Scientist opens with some cheap jokes. On the other hand, they gave Lloyd a phone call. Both articles mention use of these findings to develop drugs to promote orgasm in women. Alert feminists will note that the FDA has been slow to approve drugs that help women sexually. Women's use of viagra, for instance, has never been approved.