Read more from Slate's Sex Issue.
2007 has been a great year for sex. OK, every year is a great year for sex. But this year is especially interesting, with reports of sexsomnia, vegansexuals, man boobs, female promiscuity, double penises, horny old folks, cosmetic vagina surgery, publicly funded sex-change surgery, and the decline of marriage and co-sleeping. Among this year's hundreds of Human Nature stories, five trends and discoveries stand out.
1) Parthenogenesis. The top sex story of 2007 is … no sex. Specifically, making babies without sperm. That stuff you were told about the birds and the bees? Sorry. The truth is that males aren't necessary. In May, scientists verified a " virgin birth" in sharks. This phenomenon had previously been found in some amphibians, birds, and reptiles, but a new genetic analysis confirmed it in a hammerhead shark. The baby shark was formed by fusion of an egg with an egg byproduct from the same mother, so its DNA was a double helping of half the mom's DNA. Scientists concluded that this might explain some mysterious births to other captive sharks.
A month later, another shark fetus developed in a tank with no apparent father. No male of the shark's species was in the tank. The fetus was found because its mother died; otherwise, it would have been quickly eaten and never discovered. The implication is that births to sharks with no apparent fathers may happen more often than we realize, because when there's no male around, we don't look for offspring.
(For Human Nature's take on parthenogenesis in sharks and other animals, click here.)
2) The abolition of menstruation. The human mind is gradually conquering the human body. Case in point: In May, the FDA approved a birth-control pill that eliminates menstruation. Unlike other birth-control pills, it simply skipped the traditional week off for bleeding. The "curse" used to be defined by its inevitability. Now that's gone.
Not everyone is thrilled about this conquest, as the debate over the new pill made clear. The pill's manufacturer says: 1) Periods can be painful. 2) They ruin your mood. 3) They cost you work time and hurt your job performance. 4) They disrupt your sex life. 5) They disrupt your exercise routine. 6) There's no evidence that they're necessary to your health. 7) Your "periods" on the pill are fake anyway. But critics argue: 1) Periods are womanly. 2) They're not an illness. 3) Stop treating your body as a nuisance. 4) Don't mess with Mother Nature. 5) There's no long-term evidence that abolishing periods is safe. 6) If you don't have them, how can you be sure you're not pregnant?
(For Human Nature's take on the conquest of menstruation, click here.)
3) Digitization. Commercial sex used to be either live and in person (prostitution) or recorded and viewed (porn). Now you can combine the immediacy of prostitution with the safety of porn, thanks to entrepreneurs who plan to offer video of live, on-demand sex through hotel TVs. This is the result of several trends: 1) Americans spent $500 million last year on pay-per-view or on-demand sex videos. 2) TV is merging with computers, which facilitate private communication. 3) Computers are already allowing porn buyers to send text messages to performers. 4) Live sex on demand is more exciting than video sex on demand.
Sometimes digital sex is too real: High-definition video is embarrassing porn stars. The embarrassments include razor burn, cellulite, wrinkles, pimples, visible veins, and fake boobs. Remedies tried so far: diets, exercise, makeup, tanning spray, grooming assistance, cosmetic surgery, softening lights, changing sex positions, and airbrushing. Actresses complain that their "imperfections" are being exposed and that HD is forcing them to get boob jobs.
And sometimes sex is physically fake but emotionally devastating: Sexual couplings in Second Life are fraying real marriages. Counselors are "seeing a growing number of marriages dissolve over virtual infidelity." One wife says her husband's avatar's marriage to another woman's avatar is cheating; he says it isn't. His arguments: 1) It's just a game. 2) He has never met the woman behind the other avatar and doesn't plan to meet her. 3) His participation in Second Life is no different from his real wife watching TV. Her arguments: 1) The virtual marriage includes a joint mortgage, dogs, and spending hours together. 2) The husband and the other woman spend real money on each other's avatars. 3) The other woman says, "There's a huge trust between us. We'll tell each other everything." 4) The husband met his real wife online in the first place. 5) His virtual avatar is all about lingerie, nude dancers, and redheads, which his fake wife is but his real wife isn't. 6) He's spending all day in Second Life and ignoring his real wife.
She's right: "When it's from six in the morning until two in the morning, that's not a hobby, that's your life."
(For Human Nature's take on policing cybersex, click here.)
4. The chemical manipulation of sexual orientation. Conservatives have been coming around to the idea that homosexuality may be biological. Leaders of Exodus International, the leading U.S. ex-gay ministry, now "talk deliberately about a possible biological basis for homosexuality, in part to explain that no one can turn a switch and flip from gay to straight." This matches a new Gallup poll in which 42 percent of U.S. adults say homosexuality is innate. The old idea was that faith would free you from homosexuality; the new idea is that you still have gay inclinations, and you accept them, but you can manage them to seek harmony with your religious beliefs. Are anti-gay leaders becoming ex-anti-gays? More likely, they're just trying to manage their anti-gay inclinations.
The new factor in this debate is research on gay sheep. Eight percent of rams show sexual interest only in other rams; a researcher has been studying the biological factors involved. Critics argue that he's trying to "cure" homosexuality in rams through "prenatal treatment" and that this could lead to "breeding out" human homosexuality. He says: 1) He studies rams, not humans. 2) He's interested in understanding sexuality, not manipulating it. 3) He opposes sexual eugenics in humans. And 4) his research might assist ranchers by figuring out which rams would breed.
Unfortunately for him, scientists don't control the uses to which their research might be put. Inspired by the sheep studies, some conservative Christian leaders are endorsing prenatal treatment to prevent homosexuality. The Rev. Albert Mohler Jr., president of the Southern Baptist Theological Seminary, writes: "If a biological basis is found, and if a prenatal test is then developed, and if a successful treatment to reverse the sexual orientation to heterosexual is ever developed, we would support its use as we should unapologetically support the use of any appropriate means to avoid sexual temptation and the inevitable effects of sin." In an AP interview, Mohler says this would be morally no different from curing fetal blindness or any other "medical problem." A leading Catholic thinker agrees: "Same-sex activity is considered disordered. If there are ways of detecting diseases or disorders of children in the womb, and a way of treating them that respected the dignity of the child and mother, it would be a wonderful advancement of science." Conservatives are angry that Mohler suggested homosexuality might be biological; gays were angry that he said it would nevertheless be wrong. Mohler explained that he opposed genetic (as opposed to hormonal) intervention in the fetus and that he was trying to head off something worse and more plausible: abortions of gay fetuses.
5) What's wrong with incest? Homosexuality is the old sex-and-science debate. The new topic is incest. In Germany, a brother-sister couple is challenging the law against it. Details: 1) They were raised separately. 2) They met when he was 23 and she was 15; they began living together a year later. 3) They have four kids. One has epilepsy; two have "special needs"; three have been put in foster care. 4) The brother has served a two-year sentence for incest. 5) He recently got a vasectomy. The couple argues that 1) the law is outdated, 2) it violates their civil rights, 3) they're not hurting anyone, 4) the law already lets couples with genetic risks (due to advanced age) or hereditary diseases have kids, and 5) if incestuous couples live together and don't have more kids, how can the government prove they're having sex without becoming dangerously invasive?
But a new study suggests a secular explanation for the incest taboo: It's driven by natural selection. On average, your level of disgust at the notion of sex with a sibling correlates with how long you cohabited with that sibling and watched your mom care for her as a small child. So does your level of altruistic behavior toward the sibling. These experiential factors correlate more strongly with incest aversion than does your belief that the sibling is genetically related to you. The researchers posit a mental "kinship estimator" that converts "maternal perinatal association" into altruism and sexual disgust, driving you to choose a mate outside your family. The old idea was that nature makes you horny for your sister, but faith teaches you it's icky. The new idea is that nature tells you it's icky, and faith takes the credit.