Sex would be a very different proposition for humans if — like some animals including chimpanzees, macaques and mice — men had penises studded with small, hard spines.

Now researchers at Stanford University in California have found a molecular mechanism for how the human penis could have evolved to be so distinctly spine-free. They have pinpointed it as the loss of a particular chunk of non-coding DNA that influences the expression of the androgen receptor gene involved in hormone signalling.

The research also suggests a molecular mechanism for how we evolved bigger brains than chimpanzees and lost the small sensory whiskers that the apes — who are amongst our closest relatives and with whom it has been estimated we share 96% of our DNA — have on their face.

{ Nature | Continue reading }

artwork { Tom Gallant, Japanese Iris, 2010 | Cut paper, glass, wood }

Among the findings of a sweeping federal government survey of American sexual behavior is one that may surprise those bewailing a permissive and eros-soaked popular culture: More than one-quarter of people interviewed in their late teens and early 20s had never had sex. (…)

The uptick in abstinence is one of many revealing facts arising from structured interviews with a random sample of 13,495 Americans, ages 15 to 44, that were done from 2006 to 2008. The findings provide evidence for almost every theory and supposition about the nation’s secret sex life.

The survey results, released Thursday, suggest that oral sex may be a gateway to vaginal sex but that for some teens it is a stopping point. Most adults are monogamous. About 4 in 10 adults have had anal sex. Women are more likely than men to have same-sex liaisons. Or at least are more comfortable talking about them.

{ Washington Post | Continue reading }

photo { Saul Leiter, Lanesville, 1958 }

New research out of Brigham Young University finds that couples who wait to have sex are happier, and that delaying sex could lead to a healthier marriage. “I think it’s because [those who waited] learned to talk and have the skills to work with issues that come up,” says scientist Dean Busby, the study’s lead author. (…)


It’s possible for a man to be allergic to his own semen, according to Dutch scientists who have been studying post-orgasmic illness syndrome, a condition in which men develop flu-like symptoms after ejaculating.

{ The Week | Continue reading }

photo { Dominico Albion | more }

A difference between an addict and a recovering addict is that one hides his behavior, while the other can’t stop talking about it. Self-revelation is an important part of recovery, but it can lead to awkward moments when you meet a person who identifies as a sex addict.

For instance, within a half-hour of my first meeting Neil Melinkovich, a 59-year-old life coach, sometime writer and former model who has been in Sex Addicts Anonymous for more than 20 years, he told me about the time in 1987 that he made a quick detour from picking up his girlfriend at the Los Angeles airport so he could purchase a service from a prostitute. Afterward, he noticed what he thought was red lipstick on himself. It turned out to be blood from the woman’s mouth. He washed in a gas-station bathroom, met his girlfriend at the airport and then, in the grip of his insatiability, had unprotected sex with her as soon as they got home — in the same bed he said he had used to entertain three other women in the days before.

{ Time | Continue reading }

illustration { Richard Wilkinson }

{ 1968-75: How ‘X-Rated’ Became Synonymous With ‘Porn’ | full story }

Here’s a paper from 1985 titled, EEG during masturbation and ejaculation. In this study, they had three men masturbate and ejaculate while undergoing EEG (ElectroEncephaloGraphy). (…)

The authors didn’t really do any strong quantitative analyses of their EEG. More just qualitative observations. The methods in this paper are a great read, though. They recorded 14 channel scalp EEG. In addition, they also recorded:

“Anal Contractions” with a “pressure-sensitive anal probe”.

“Penile Tumescence” with a “mercury strain gauge”. Unfortunately, “[t]he masturbatory movements interfered with the recording”.

“Wrist Accelerometer” that was “taped to the dorsum of the hand (right) used in masturbation”.

And the procedures really give you a sense of the beauty of the entire setup: “Subjects were instructed to avoid unnecessary movements, and their compliance was verified by video monitoring of head and torso throughout the session. (…) The average length of masturbation to the first anal contraction was 402 seconds.”

{ Oscillatory Thoughts | Continue reading }

photo { David Stewart }

First we must ask Why does a woman (or a man, for the matter) vocalize during sex at all? Sure, there might be a host of valid social reasons - one might be to boost the ego of the man [92% of the women in study agreed to this statement, and 87% reported vocalizing for this very purpose] (Brewer and Hendrie, 2010), or to deceive the man that they are a competent lover (68% of women reported wanting to stay with a man even though he never helped her climax) (Brewer and Hendrie, 2010).

But from an evolutionary perspective we must be mindful of a few things: First, men do not vocalize in the same manner as women. Second, comparative evidence in chimps suggests that vocalizations are for attracting more males to a sexual encounter (in order to have more sex), which is further supported by the fact that when chimps are engaging in down-strata copulation (that is, if the women is having sex with someone she ’shouldn’t’ be having sex with) she still makes chimpanzee sex-faces, but fails to make the vocalizations.

{ Psycasm | Continue reading }

painting { Erik Mark Sandberg }

…50-year-old Nobuhiro Komiya who for the last two years has worked tirelessly doing one of the most unlikely and mind boggling of jobs - censoring the unending torrent of hentai manga or pornographic comics which flood Tokyo’s book shops and convenience stores.

“It’s a tough job. (…) It’s totally different to reading manga as a hobby,” he says.

A visit to the Department of Youth Affairs and Public Safety on the 35th floor of Tokyo’s towering Metropolitan Government building, where Komiya and his small team of censors get down to the grisly task of comic book censorship, reveals we are talking about a lot more than the width of Wonder Woman’s bust.

Spread out over the white Formica table-top are the worst of the worst - a hand-picked selection of the weirdest and most shocking examples of hentai from the country which invented it.

“Normal sex doesn’t sell well,” Komiya remarks. School sex, tied-up sex, abnormal sex, sells. So this is what they draw.”

{ NZ Herald | Continue reading }

photo { Asha Schechter }

“My lover thrust his hand through the hole,” she says, “and my insides groaned because of him.”

This ode to sexual consummation can be found in—of all places—the Bible. (…)

What does the Bible really say about sex?

{ Newsweek | Continue reading }

Accord­ing to a recent study com­mis­sioned by the Japan­ese gov­ern­ment, the country’s desire for sex is drop­ping quickly.

The bien­nial sur­vey, orig­i­nally designed to gauge the suc­cess of the country’s birth-control edu­ca­tion, revealed that 36.1 per­cent of Japan­ese males between 16 and 19 had no inter­est in or even loathed sex. In 2008, that num­ber was 17.5 percent.

Of girls in that 16–19 age group, 59 per­cent had no inter­est in sex, up 12 points from 2008.

Forty per­cent of mar­ried peo­ple admit­ted to not hav­ing sex within the last month.

Over­all, the fer­til­ity rate in Japan has dropped to 1.37 births per woman. It’s 2.06 in the U.S. Such a low rate, if it con­tin­ues, could have major con­se­quences for the Japan­ese economy.

{ Good Feed | Continue reading }

image { Amazon.com }

A good reason not to try sex in space. Yet.

One of the dominant ideas for getting to another solar system within the next few centuries involves the generation ship, vast spacecraft designed to function as their own, self-contained colonies and housing thousands of humans for very long stretches of time, ideally with all the comforts of home. And one of those comforts better be gravity because it turns out that if humans were to start reproducing without that familiar acceleration of 9.8 m/s/s or pretty close to it, their children are likely to be born with cranial defects, collapsed jaws, and buckled spines, among some of the other pleasantries of embryos’ inability to cope with a lack of gravity during the development process.

{ Weird Things | Continue reading }

photo { James O’Mahoney}

When we cry, we may be doing more than expressing emotion. Our tears, according to striking new research, may be sending chemical signals that influence the behavior of other people.

The research, published on Thursday in the journal Science, could begin to explain something that has baffled scientists for generations: Why do humans, unlike seemingly any other species, cry emotional tears?

In several experiments, researchers found that men who sniffed drops of women’s emotional tears became less sexually aroused than when they sniffed a neutral saline solution that had been dribbled down women’s cheeks.

{ NY Times | Continue reading }

artwork { Jules Joseph Lefebvre, Mary Magdalene In The Cave, 1876 }

I’ve been dating this guy and the other night we finally took our clothes off. To make a long humiliating story short, he ended up admitting to me that I was too hairy. I’m okay with it, why can’t he be?

Now, as much as I would love to tell you that you are right, listen to me when I say, “You wanna be right or you wanna get laid? (…)

Also, remember, there is the “fun” part where you can pick your own design. The two most popular are the “landing strip” and the “Bermuda Triangle.”

Comments

Posted by Melsy
This is the WORST excuse for “advice” I have ever read! Go find a real man who doesn’t want a little girl’s vajayjay.

Posted by Giz
Horrible column. (…) Moreover, removing all hair is painful, doesn’t last long and leaves the area more open to infection. Nothing about it is attractive.

Posted by J
Please get rid of it, the area in question is the most beautiful landscape on the planet, and I would like to see it.

{ Shine/Yahoo | Continue reading }

image { imp kerr, study after courbet’s l’origine du monde, 2008 }

The first brain scans of men and women having sex and reaching orgasm have revealed striking differences in the way each experiences sexual pleasure. While male brains focus heavily on the physical stimulation involved in sexual contact, this is just one part of a much more complex picture for women, scientists in the Netherlands have found.
The key to female arousal seems rather to be deep relaxation and a lack of anxiety, with direct sensory input from the genitals playing a less critical role.

The scans show that during sexual activity, the parts of the female brain responsible for processing fear, anxiety and emotion start to relax and reduce in activity. This reaches a peak at orgasm, when the female brain’s emotion centres are effectively closed down to produce an almost trance-like state.

The male brain was harder to study during orgasm, because of its shorter duration in men, but the scans nonetheless revealed important differences. Emotion centres were deactivated, though apparently less intensely than in women, and men also appear to concentrate more on the sensations transmitted from the genitals to the brain.

“Men find it more important to be stimulated on the penis than women find it to be stimulated on the clitoris,” Gert Holstege of the University of Groningen said.

This suggests that for men, the physical aspects of sex play a much more significant part in arousal than they do for women, for whom ambience, mood and relaxation are at least as important. (…)

The experiments also revealed a rather surprising effect: both men and women found it easier to have an orgasm when they kept their socks on. (…)

The scans also show that while women may be able to fool their partners with a fake orgasm, the difference is obvious in the brain. Parts of the brain that handle conscious movement light up during fake orgasms but not during real ones, while emotion centres close down during the real thing but never when a woman is pretending.

{ Times | Continue reading }

photo { Germaine Krull }

The slasher horror film has been the subject of frequent criticism based on the assumption that female characters in these films are more likely to be the victims of serious, graphic violence that is juxtaposed with explicit sexual imagery. The purpose of this study was to address limitations inherent in previous analyses of slasher films and examine whether gender differences exist in the nature of violent presentations. A content analysis of several indicators of violent and sexual content was conducted using a random sample of 50 slasher films that were released in North America between 1960 and 2007. Findings suggested that there are several significant gender differences in the nature of violent presentations found in slasher films. In general, female characters were more likely to be victims of less serious and graphic forms of violence, but were also significantly more likely to be victimized in scenes involving a concomitant presentation of sex and violence.

{ Sex and Violence in the Slasher Horror Film: A Content Analysis of Gender Differences in the Depiction of Violence by Andrew Welsh, Ph.D., Department of Criminology and Contemporary Studies | PDF }

Sex costs amazing amounts of time and energy. Just take birds of paradise touting their tails, stags jousting with their antlers or singles spending their weekends in loud and sweaty bars. Is sex really worth all the effort that we, sexual species, collectively put into it?

Most biologists think that sex is totally worth it. With sex, every new generation receives a fresh combination of genes from its parents. This makes it easier to adapt to changing environments, as genes can spread quickly through a population.

In asexual species every child will be genetically identical to its parents, making it hard to compensate for disadvantageous mutations. Biologists expect that deleterious mutations will pile up in asexual species in a process known as Muller’s ratchet. With every mutation in an asexual lineage, Muller’s ratchet clicks one step closer to extinction.

{ Scientific American | Continue reading }

photo { Glenn Glasser }

Nobel prize nominee Umberto Veronesi raised some controversy a couple of years ago when he stated that he believed humanity was moving towards a bisexual future. The famous oncologist was not just looking to raise havoc. He actually had some good points to make. For example, he cited the scientific fact that the vitality of male reproductive cells has gone down by 50% since the end of World War II.

Based on evidence about the dissociation between sexuality and reproduction, the endless possibilities of artificial fertilization, and the fact that men and women are producing less and less hormones every day, Veronesi predicted that, as sexual interaction will lose its mainly reproductive function, bisexuality will become the norm rather than the exception.

{ Brain Blogger | Continue reading }

Women are getting as good as they’re giving. By ages 25-29, 88 percent say they’ve received oral sex from a man, and 72 percent say they’ve received it in the last year. (…)

In 1992, 16 percent of women aged 18-24 said they’d tried anal sex. Now 20 percent of women aged 18-19 say they’ve done it, and by ages 20-24, the number is 40 percent. In 1992, the highest percentage of women in any age group who admitted to anal sex was 33. In 2002, it was 35. Now it’s 46. (…)

Among women who had vaginal sex in their last encounter, the percentage who said they reached orgasm was 65. Among those who received oral sex, it was 81. But among those who had anal sex, it was 94. Anal sex outscored cunnilingus.

No way, you say. Way. Read the data.

{ Slate | Continue reading }

Assuming you’re in a heterosexual relationship, which is worse: for your partner to be unfaithful with a person of the opposite or the same sex?

According to a pair of US psychologists, the answer depends on whether you’re a man or woman. Men, they’ve found, are less likely to continue a relationship with an unfaithful partner who’s had a heterosexual affair, as opposed to a homosexual affair. For women, it’s the other way around - they’re more troubled by their male partner going off with another man.

{ BPS | Continue reading }

My last post said teen males want more sex than teen females. Older men also often complain of women withholding sex, while women complain of men demanding too much sex. From a typical top ten complaints list:

[Women About Men:] 3. They are not affectionate enough. 4. They tend to bypass sexual foreplay.

[Men About Women:] 1. Women complain, criticize and nag too much. …  4. They tend to withhold sex as a punishment or blackmail.

This is often explained in part via women just caring less about sex than men.

{ Overcoming Bias | Continue reading }