The initial study was conducted in 1948 by Angus J. Bateman, who showed that female fruit flies had fewer mating partners and their overall offspring had less genetic diversity than male fruit flies' overall offspring.

Bateman concluded that, because a single egg is more costly to produce than a single sperm, the number of offspring produced by a female fruit fly was mainly limited by her ability to produce eggs, while a male's reproductive success was limited by the number of females he inseminated. These studies supported the conventional assumption that male animals are competitive and promiscuous while female animals are non-competitive and choosy.

No one disputes the accuracy of Bateman's work, just its indiscriminate application to human behavior without any regard to social of cultural factors. A new study by Dr. Gillian R. Brown at the University of St. Andrews seeks to provide more depth to our understanding of human sexuality.

"The conventional view of promiscuous, undiscriminating males and coy, choosy females has also been applied to our own species," says lead study author Dr. Gillian R. Brown from the School of Psychology at the University of St. Andrews. "We sought to make a comprehensive review of sexual selection theory and examine data on mating behavior and reproductive success in current human populations in order to further our understanding of human sex roles."

That's a rather generous explanation for the acceptance of a model that conforms to cultural norms and expectations of men and women's roles in society and reinforces the idea that women who aren't seeking to settle down with one sex partner are somehow dysfunctional, but ok.

Brown's study, as The Telegraph reports, actually looks at, you know, human behavior.

The study of more than 10,000 people in 18 countries seems to throw on its head the generally accepted expectations that men tend naturally towards promiscuity and women are more particular when it comes to choosing a mate.

Hooray!

What else does it say? Plenty, according to Live Science writer Sally Law.

However, Gillian R. Brown, a professor at the School of Psychology at the University of St Andrews and the study's lead researcher, says that the research also found big differences among populations on the patterns of reproductive success for men and women.

For example, the study cites societies in Botswana, Paraguay and Tanzania in which women – not just men – conceive children with multiple partners.

As is sometimes the case even in America, what with divorces and single parenthood not exactly out of the question.

But there's more!

"Evidence for sex differences in variation in reproductive success alone does not allow us to make generalizations about sex roles, as numerous variables will influence [Bateman's findings] for men and women," Brown writes.

Population size is one such variable: both men and women will be selective about mates when there are lots of options - in a large city, for example. Conversely, neither gender will be choosy in low-population areas. In such a scenario, both men and women will take what they can get.

That probably explains why every woman in every major city I know complains about how their city is the worst to date in.

But Brown's research does show that overall, across the 10,000 subjects in 18 countries, men tended to have more children by different women than women did by men. That, though, requires a fairly basic statistical explanation.

Brown's research also addresses the issue of reproduction within a monogamous partnership; while only 16 percent of societies have monogamous marriage systems, they make up a large percentage of relationships in the developed world. In such societies, variances in male and female reproductive success were similar. Furthermore, in half of the world's polygamous marriages - which account for 83 percent of the world's societies - less than 5 percent of men take more than one wife.

You might be wondering why Brown only looks at reproductive success (the number of mates by whom people have children) versus the number of sex partners. Well, it turns out that's because we all lie about it.

Here is why: the studies reporting these statistics are scientifically unsound, she said, which helps explain the mathematical difficulties in research that finds that men have more sex partners than women. (One such study, conducted by the National Center for Health Statistics, claims that men have an average of seven sex partners during their lifetime, while women have four.)

"[The reported numbers are] logically impossible if we're assuming these are heterosexual interactions and that all individuals have been questioned," Brown says. "We were particularly interested in asking whether the variance (not average) in mating success differs between men and women, but questionnaire studies don't seem to be a sufficiently reliable source of evidence."

In other words, men may be exaggerating upwards, but women are probably also exaggerating downwards, contributing to the expectation that men will have more sex partners and women fewer.

And it's not just women who are being judged. The social expectation for men to sleep around — particularly in the developing world, where Brown's research shows the greatest variance in reproductive success between men and women — is toxic for society at large and the people in it.

Newswire IRIN is running an interview with Purmina Mane, an executive director of the UN Population Fund, who says the idea that men should have multiple sexual partners, take risks, are resilient to disease, reject contraception and be too strong to ask for help continue to affect access to healthcare and reproductive health services and is increasing exposure to the HIV virus for both men and women.

"Late diagnosis and treatment means that many continue to practice unprotected sex, running the risk of reinfection and of unknowingly infecting their partners," said Mane.

I guess the Pope's abstinence-in-Africa-you-don't-need-condoms is working?

Others agree with Mane.

The story also quotes Graca Sambo, an executive director of Forum Mulher, a women's rights NGO in Mozambique, which said the idea that men should have many different sexual partners was a major contributing factor to the country having one of the highest HIV prevalence rates in the world – 16%.

"A lot of men have many sexual partners because this is what is expected of them," she said. "Masculinity is very much instilled by culture and by tradition, which say that men have to be studs."

Which, of course, backs up Brown's findings that promiscuity in men is by no means biological — but it does fit into preconceived notions about expected and appropriate behavior for men and women, which, it turns out, is good for none of us.

Evolution Of Human Sex Roles More Complex Than Described By Universal Theory [EurekAlert]
Men Are No More Promiscuous Than Women, Survey Finds [Telegraph]
Basis for Male Promiscuity Questioned [Live Science]
How Can We Change 'Macho' Attitudes To Sex? [The Guardian]

Cutler's fiancé, Charles Rubio, is a 28-year-old New York lawyer that Cutler told Gawker she met in a bar last March. I think we can all assume that Rubio has basic reading and Google skills and — having known Cutler for the last 9 months or so — a pretty good idea of what she's done, who she is and why he wants to spend his life with her. Why is is so improbable that a woman who enjoys sex, has had multiple partners, has written about it and who has had heaped upon her humiliation, public opprobrium and a lawsuit by an ex-lover, could fall in love? Is it so improbable that a woman such as Cutler could have found love, could be ready to build a life with someone that loves her, or could manage to beat the (statistical) odds of divorce that confound every couple willing to take the plunge?

But, let us be honest here. It's not because people think Cutler has "issues" — plenty of people with issues get married every day, and some of them stay that way. It's not because people know enough about Cutler to assess her ability to have and maintain long-term relationships — although, to point out, the blog that catapulted her into the public spotlight was meant for several long-term friends of hers, so she can apparently maintain relationships with people over the course of a few years. It's not because anyone commenting snidely on her chances of being happy knows anything about how she comports herself in a relationship, feels about Rubio, how Rubio feels about her or what they both want out of a marriage (and whether they've discussed that). It's because they think that, having allowed a number of different men into her bed, she's not the "kind" of girl who can settle down.

Let's try thinking about what Cutler and Rubio have going for them. Rubio can hardly have any illusions about the woman he's marrying — but he loves her and wants to spend his life with her. And, honestly, that's kind of sweet, and cool, and what you want in a life partner — someone willing to shoulder your burdens with you and take on the world with you. And Cutler, sure, she's slept with a bunch of guys and maybe drank too much, but there was something about this guy that made her want something more. He bought her a bracelet she liked because he thought it would be harder to lose than a ring, and she didn't whine about not having a ring just because it's what society demands. She likes that he asked her father first, and, when e-mailed for comment, he deferred to her for comment. It actually sounds like they know each other pretty well and have their shit together. So why is it that people seemingly think they are so much more likely to end up screaming at one another in divorce court?

Which is not to say they won't. Marriage is tough. Maybe it will all blow up and the people who like to point and tsk-tsk about women who aren't ashamed to have lots of sex will have another reason to say that women like Cutler don't get to be happy. But there is at least one person hoping that, despite the obstacles that will get thrown before them and the shitstorms that will rain down on them no matter what they do, that it does work out for them both... if only because seeing other people happy doesn't inspire disgust or envy as much as it helps keep alive the small flicker of hope that anyone can be.

Washingtonienne Jessica Cutler Engaged [Gawker]
Jessica Culter Is Engaged [DCist]

• If you think someone is promiscuous, you might well be right.
  In a recent study conducted in the UK and published in Evolution and Human Behavior, Lynda Boothroyd showed that both men and women were able to judge the openness of men and women to a sexual fling based on photographs of their faces. The study showed that both genders judged men who looked "masculine" and women that looked "attractive" as, correctly, more open to casual sex.
• Who a woman wants to sleep with — and her openness to doing so — varies with her cycle and her age.
  A variety of studies have shown that women get hornier right before they ovulate, and a study by David Schmitt of Bradley University shows that women's preferences in men vary around the same time. In addition, another study conducted in 48 countries shows that women's openness and propensity to engage in intercourse with multiple sexual partners (including infidelity) peaks in her 30s, while, for men, it peaks in their 20s. Schmitt hypothesizes that this is because women's fertility begins to decline at that point in her life.
• It does have to do with your mommy (or daddy) issues.
  Jay Belsky, in study published in Child Development, found that women who grew up in stressful family situations tended to have more kids early without waiting for stable relationships because, he hypothesized, they were sure one was coming. He wrote, "harsh parenting in the first four years of life predicts early puberty and growth and thereby predicts more unrestricted sexual behaviour by the time the child reaches 15 years of age."
• It's still about trust and security.
  A variety of studies of both men's and women's propensity to sleep around is based in their ability to trust or feel secure in relationships. Schmitt says, "If a person was high in being able to trust other people, they were monogamous. If they were very low in trust they were much more likely to be unrestricted in sociosexuality." He relates this, like Belsky, to childhood stresses and poor relationship models.
• Sleeping around might be related to testosterone in both sexes.
  A study Sarah Mikach and Michael Bailey of Northwestern University looked at the correlation between a woman's sexual partners and how they look, felt or acted more stereotypically masculine and found, somewhat unsurprisingly, that woman who were identified as more "masculine" tended to have more sexual partners. Of course, it all depends on the definition of "masculine behaviors," but even when just taking biology into account, the theory seems to hold. Researchers believe that having a longer ring finger than index finger is related to prenatal testosterone exposures — and a study by Andrew Clark in Evolution and Human Behavior found that women with longer ring fingers tended to have more sexual partners as well.
• Oh, and, yes, there is a social aspect to all of this.
  Biology is all well and good, but thousands of years of judging male and female sexuality differently does have more than a little something to do with women's ability to act on their legitimate sexual desires. Schmitt points out that, with the expansion of birth control, education, and access to social services for women, their ability and willingness to act on sexual urges definitely increases. Fhionna Moore at the University of St Andrews found in her work that financially independent women didn't tend to seek out so-called "good providers," as much as they did supposedly good jeans genes. Basically, once a society begins to near equality for men and women, providing women with more autonomy and less of an incentive or requirement to buy into patriarchal sexual mores, they don't — and then many of them go have a bunch of sex.

While humans are biologically driven to mate like any other species, the many, varied aspects of how, why and when we mate and (sometimes) bear children never seemed fully explained by "Women are biologically determined to be taken care of by a man." So, it's nice to see a group of scientists try to tease out which aspects of human sexuality and coupledom are actually biological and which are socially-driven after so many decades of viewing thousands of years and biological and social evolution through a (social) nuclear family lens.

The Dizzying Diversity Of Human Sexual Strategies [New Scientist]

Some people might sleep with multiple partners not because they are selfish but because they view sexual activity as an extremely warm activity and want to share it with others.

Eh, I still say I do it because it's just fun. And that would place me in the cold/distant category, which means, if you're like me, we "avoid serious relationships and the attendant risk of rejection," or we "just want to have as much fun as possible with no regard for the feelings of others." Yeah, that second one, I think. But really, it doesn't matter to me if I'm warm or cold, just as long as my partners are hot. (Ba dum bum.)

Promiscuity: Spread The Love [Psychology Today]

• The STD of yore, syphilis, is back, baby, and on the rise in New York City! This obviously has nothing to do with Zach Braff being in town all summer. [NY Times]
  
• Kate Hudson may think that men are whores by nature (and that it's okay!), but nerds beg to differ. UC Berkeley math professor Dr. David Gale says it's mathematically impossible for men to have more sexual partners than women — we would tell you more about the handy-dandy equation he uses to back up this claim, but we didn't quite get it. [NY Times]
  
• An alarming percentage of women are unaware that HPV can cause cervical cancer and even fewer know that there is a vaccine available. Now you know ladies, so get thee to Dr. Pap Smear and thank us later. [BBC News]
  
• A 13-year old Egyptian girl died during a circumcision procedure, only a few weeks after a similar death prompted health officials in the country to ban the heinous practice. [Fox News]

• Maryland police accidentally let a sexual assault suspect go after they arrested him for molesting a 9-year old girl. The perv is still on the loose. Way to fucking go, Maryland PD. [Fox News]
• Yay, Ohio! The state's Civil Rights Commission is pushing for companies with four or more employees to grant their workers 12 weeks of unpaid maternity leave, regardless of how long they've worked for the company. Wait, unpaid? That sorta sucks, actually. [NY Times]
• Irene Morgan Kirkaldy, a Civil Rights pioneer whose refusal to make room for a white bus passenger preceded Rosa Parks by a decade, has died at the age of 90. [NY Times]
• Dr. Howard Judd, whose expertise in menopause led to significant advances in estrogen and hormone treatments, died at the age of 71. How he knew so much about hot flashes, we'll never know. [NY Times]
• A new study shows that taking a birth control pill for an extended period of time can affect fertility down the road. [Telegraph]
• The latest trend in bodice rippers comes out of Australia, as romance writers are penning hunky heroes that are more like your average Joe. Eh, we prefer the perviness of VC Andrews incest-laden paperbacks anyday. [Reuters]
• In the stupid legal battles department, some schmo is suing 1-800-Flowers for $1 million for revealing his affair to his wife. Something tells us he's going to have a hard time getting a date after this. [ABC News]
• We're not sure where we stand on the Mexico City street vendor debate — aside from the fact that we think the tacos are super tasty — but we do think the woman fighting the Mayor's plans to clean up the city is one bad-ass great grandma. [LA Times]

• Have you heard? This 26-year-old woman — 9 months pregnant — has been missing for almost a week. Are you as sick and tired of hearing about abducted and assaulted young women and girls as we are? [CNN]
  
• The fewer female relatives a woman has, the more likely she is to contract a certain type of breast cancer. [ABC]
  
• Women more likely to die from diabetes than men. Could this have anything to do with some of them leaving the disease untreated in order to lose a few fucking pounds? [Chicago Tribune]
  
• More adolescent girls — particularly 19-year-olds —are having abortions than ever before in the U.K; this news comes one week after UK officials announced that teens in England and Wales are "in the grip of a sexual health crisis, fuelled by a 'celebrity culture' that condoned alcohol abuse, drug addiction and promiscuity." [Telegraph]