Happy National Orgasm Day

Today, I have just learned from Katherine Feeney’s column in the Sydney Morning Herald, is National Orgasm Day. What that is and how you celebrate it remains a little opaque to me*. Will there be organised pageantry and fireworks later on? Should one share this knowledge with a loved one? Or simply mark the occasion alone?


But my recent post on the function of orally-induced orgasm stimulated so much discussion, I thought I’d dip into the pages of Archives of Sexual Behaviour for an appropriate reading to mark NOD. And the journal did not disappoint.

The paper I chose, so steaming hot out of peer review that it has only just been published online, concerned female orgasm as a signal. Readers of my previous column might recall my irritation that the social feedback of unselfish stimulation and orgasmic response seemed to be a missing dimension in the Evolutionary Psychology paper that precipitated that post.

Today’s paper tested two predictions concerning womens’ orgasms as signals. First, that orgasms signal a woman’s sexual satisfaction and thus her likely fidelity as a partner (the Female Fidelity hypothesis). And second that women orgasm to signal an increased chance of conception (the Sire Choice hypothesis). Yes, I know it seems a little man-centric to frame these questions with reference to the man, rather than the subject of the orgasm herself. But at least we’re talking about orgasms as part of the give-and-take commerce of sex and satisfaction.

The authors, Ryan M. Ellsworth from the University of Missouri and Carnegie Mellon’s Drew H. Bailey, administered a questionnaire to 138 women and 121 men, each currently in a heterosexual romantic relationship. Through a rather exhaustive bank of questions, they estimated each participant’s relationship satisfaction, partner investment, sexual fidelity, sexual behaviour and orgasm history.

Women reported orgasming during sexual intercourse 61 percent of the time. More than half of the women (58%) reported faking orgasms sometimes, with 18% of copulations with current partners resulting in faked orgasms. Men, you might not be surprised to learn, underestimated the rate of faked orgasms. Only 21 percent reported that their partners faked, and only estimated that women faked about 5 percent of the time. Women who faked a lot also reported having fewer real orgasms.

The other main findings by which Ellsworth and Bailey tested their hypotheses included:

  • Women satisfied in their relationships also reported orgasming more intensely and more frequently.
  • Women whose partners invested plenty of effort in them and their relationships also had more intense and more frequent orgasms.
  • Women who reported past infidelity reported having more orgasms.
  • Women who report being open to future opportunities for infidelity reported having more orgasms, and more intense orgasms.
  • Women who reported having past infidelity or openness to future infidelity also reported more frequently faking orgasms.
  • Men in satisfying relationships reported higher rates of partner orgasm and lower rates of partner faked orgasm.
  • Men who have been unfaithful to their partners report that those partners have fewer orgasms.

Taken together, these results suggest that female orgasm and faked orgasm are involved in the quality and dynamics of the relationship, but in more nuanced and complex ways than predicted by the two hypotheses being tested. Female orgasm does not seem to signal female fidelity, and frequent, intense orgasms don’t seem to convince men of their partner’s fidelity. Instead, it seems that faked orgasms are associated with past and likely future infidelity.

It seems more likely that genuine orgasm is either a happy cause or a thrilling consequence of relationship satisfaction. So far so good, but it also seems that a high rate of both true and faked orgasm makes for an especially high chance of infidelity. Given the prevalence of the faked orgasm, and men’s ineptitude at detecting it, perhaps this is one of those cases in which the fake is at least as interesting as the original?

Well, scientifically at least.

* I have elsewhere seen it claimed that National Orgasm Day is to be celebrated on every day that ends in a “Y”

Rob Brooks does not work for, consult to, own shares in or receive funding from any company or organisation that would benefit from this article, and has no relevant affiliations.

The Conversation

This article was originally published at The Conversation.
Read the original article.

Our foraging ancestors weren’t particularly war-like

Few subjects more predictably animate furious disagreement and cross-purposes discussion than the origins of human warfare. Are people “naturally” belligerent? And what does that even mean?

The question taps a deep old well of ideological intuition. Were the lives of our ancestors, as Thomas Hobbes’ infamously put it in the 17th century, “nasty, brutish and short”? Or, were our ancestors more like the “noble savages” of romantic primitivism? Our beliefs about these issues colour whether we feel our lives are generally better or worse than those of our ancestors.

This dichotomy, in more nuanced forms, has haunted and at times paralysed anthropology since at least the 19th Century. And it reared its head again recently with the divisive reception granted to books such as Steven Pinker’s The Better Angels of our Nature, and Jared Diamond’s The World Until Yesterday, as well as a flurry of renewed interest in controversial anthropologist Napoleon Chagnon.

Steven Pinker outlines his case that violence has steadily declined throughout history

From my reading, the evidence stacks pretty solidly in favour of Pinker’s thesis that violence has decreased dramatically throughout human history. As John Armstrong put it in his review of Pinker’s book, The World Has Never Been as Safe and Peaceful as it is Now. But Pinker continues to attract considerable static, particularly from those quarters where pessimism about modern life and paranoia about Western imperialism run hottest.

But the overall battle over the decline of violence is but one theme in the history of violence, a history replete with intriguing sub-plots. The prevalence of warfare among mobile forager band societies occupies a place of particular controversy among anthropologists who actually work in the field.

Until 10,000 years ago, the ancestors of everybody alive today lived in small nomadic bands and foraged what food they could catch or gather. Most of our species’ recent past – hundreds of thousands of years – was spent hunting, gathering and moving about in this way. As a result, accounts of human adaptation often consider in some depth this period, given its importance in determining which genes and traits our ancestors bequeathed to us.

A small number of “mobile forager band” (MFB) societies still exist – or persisted long enough for anthropologists to study them systematically. It is from these peoples that we draw almost everything we know about the way our ancestors lived until the seismic changes wrought by agriculture.

From modern accounts of MFB societies we can infer that our ancestors were certainly violent. Ethnographies document homicidal personal disputes, spousal killings, fights among men over women, executions of outsiders and inter-group killings.

But were our MFB ancestors war-faring? War, here, is a subset of lethal violence that involves members of a group working together to overcome members of other groups. It’s one of those appalling human traits that romantics would like to pretend doesn’t happen elsewhere in the animal world. But ants, by this definition, certainly wage war among colonies. And Jane Goodall’s discovery in the early 1970s that chimpanzees from one group occasionally work together to kill members of other groups suggests our closest living relatives look pretty war-like too.

Harvard Anthropologists Richard Wrangham and Luke Glowacki argued in a recent paper that our ancestors waged chimp-like warfare, launching coordinated surprise attacks on other groups. Raids of this sort, in order to weaken other groups, or capture livestock, property or women, are a feature of every society that has domesticated livestock, horses or agricultural crops. But these societies tend to involve bigger, more complex groups, and forms of wealth more worth fighting over than MFB societies.

Mobile forager bands have more characteristically egalitarian political structures, less coalition-forming behaviour, and few resources or possessions worth defending. These properties don’t make good ingredients for war-mongering. So it’s really worth knowing just how much of MFB violence can be considered warfare. As my post-doc advisor was occasionally heard to say:

Just get the data!

Last week’s edition of Science contained an exhaustive analysis by Douglas P. Fry and Patrik Söderberg, who scrutinised the existing accounts of all lethal violence in 21 MFB societies. They tabulated the causes of 148 cases of lethal aggression, and found that two thirds originated from within-group conflicts. The majority of these deaths were caused by a lone perpetrator.

Only one third of events could possibly be construed as acts of warfare. And most of these events occurred in one society – the Tiwi of northern Australia in which ethnographers documented several intergroup disputes and revenge-seeking cycles. In the other 20 MFB societies only around 15% of deaths by lethal aggression could possibly fit the definition of war.

The authors concluded that:

most incidents of lethal aggression among MFBS may be classified as homicides, a few others as feuds, and a minority as war.

Refreshing as it is to see a calm, data-driven approach to answering a tightly-proscribed research question, the prevailing discussion over the last week has fallen into old ruts.

“War arose recently” proclaimed ScienceNews. Fair enough. I don’t think Fry and Söderberg would contest the argument that agriculture and the rise of complex societies made war a worthwhile – in the economic sense rational – option. And that stoked the body count.

But the Socialist Worker led, as it does, the charge against scientific accounts of human nature. War Not Due to Human Nature it proclaimed, reeling off a link-fest of SW diatribes against scientific accounts of human behaviour, and then linking to a somewhat more considered piece from Slate.

I’m happy to grant that these data show that MFB societies don’t make as much war as agriculturalists and pastoralists, not to mention contemporary weapon-rich societies. But I’m intrigued about the Tiwi, who don’t fit the mould. I’m not familiar with the data, but according to ScienceNews, Samuel Bowles reckons the Tiwi were among the more peaceful hunter-gatherer societies he studied in an earlier Science paper that reached more bleak conclusions about the history of war.

And I’m equally intrigued by how societies can tip so quickly into belligerence as soon as they settle down and accumulate some wealth. The capacity to form coalitions and deploy them for ill may have been there all along.

Where did that come from?

Rob Brooks does not work for, consult to, own shares in or receive funding from any company or organisation that would benefit from this article, and has no relevant affiliations.

The Conversation

This article was originally published at The Conversation.
Read the original article.

Don’t sleep with mean people

By Rob Brooks

That’s the message uber-cerebral Canadian rapper Baba Brinkman wants to spread. He’s Crowdfunding a music video and short documentary in support of what he calls the new Golden Rule of Sex.

Video for Baba Brinkman’s “Don’t Sleep with Mean People” Crowdfunding campaign

How cool can an artist be who debuted rapping the Canterbury Tales, moved on to Evolution and Human Nature and is now rapping about the biology of cancer (see Revenge of the Somatic)?

Plenty, if you ask me. And his ability to condense complex theories and evidence into pithy, whip-smart performances win him admiration from scientists and science-lovers wherever he takes his shows. Those shows have thrived off-Broadway and at Edinburgh fringe. And he incorporates peer review by scientists*.

The placard says it all. johndrogers on Flickr
The placard says it all. johndrogers on Flickr

The hippies taught us that “Bombing for Peace is Like Fucking for Virginity”, but the generation of free love never really answered to my satisfaction whether it is possible to fuck for peace. Can we transform a society by some form of erotic collective action? And isn’t it worth a try anyway?

Brinkman’s art provides a never-ending supply of teachable moments. His broader point is that every time a still-fertile heterosexual chooses a mate, every time one decides whether to get naked with somebody, they contribute to the process of sexual selection. Prefer people who can express themselves coherently and in full sentences? You’re selecting for smarts. And your kids may have a chance of passing the dreaded Selective High Schools test. Geoffrey Miller made a compelling case in The Mating Mind that our prodigious human intelligence arose as a result of sexual selection operating this way over many millenia.

There’s a question of timescale here. Obviously no deliberate campaign, Crowdfunded or not, is going to effect mass changes in gene frequencies anytime soon. Concerted campaigns of directed sexual activity are more likely to work by shifting incentives for good behaviour. “Behave badly and you aren’t getting any”.

Brinkman himself draws inspiration from the efforts of Lysistrata and her band of war-weary Athenian women in Aristophanes’ 411 BC play. By witholding sex from all Athenian men, they effected the end of the Peloponnesian War. Yet for most of us, collectively or individually training our mates, like Sea World dolphins, just isn’t practical.

Come over to the Dark Triad

In general, people don’t set out to mate with mean people. But, unfortunately, some of the meaner traits in the human repertoire seem to elevate mating success. Work by Peter K. Jonason (now at the University of Western Sydney), Norman P. Li and collaborators reveals that people expressing the ‘Dark Triad’ traits – narcissism, Machiavellianism and psychopathy – are more successful at initiating new sexual relationships, especially when poaching or being poached by somebody in an existing relationship. When it comes to long-term relationships, those in whom the Dark Triad is strong don’t fare so well.

It might seem a little obvious; psychopaths, narcissists and Machiavellian types, uninhibited by the pain and inconvenience they might cause others, get more matings but can’t sustain exclusive monogamy as well as other people. But the key here is that any genes underpinning Dark Triad traits get passed on whenever one of those short-term matings succeeds. And without the encumbrance of empathy or a commitment to monogamy, that can mean a lot of successful matings – especially for men.

So don’t sleep with narcissists, manipulators or psychopaths. Great advice we wish our mother had given us when we were young. Actually, she probably did when she warned us against that bad girl or boy. And yet there is no denying the lust-inducing appeal of the right level of badness.

Bombing for virginity

2013’s most bewildering bad boy is accused of genuine, world-shaking badness. He is Dzhokhar Tsarnaev, accused of carrying out April’s devastating bombing of the Boston marathon with the help of his now-dead brother. And he controversially graces the cover of August 3’s issue of Rolling Stone.

The controversial cover of Rolling Stone’s August edition, featuring Dzhokhar Tsarnaev under the headline “The Bomber”. EPA/Rolling Stone


You won’t count me among those boycotting the issue. In fact I’ve already been to the news agent, only to find it hasn’t reached our shores yet. And in the 60 seconds I was in the shop, another person asked for it. I’m predicting this issue will sell more copies than any other since the start of the GFC.

Andy Ruddock has already done a marvellous job dissecting the cover and discerning why Rolling Stone did what they did. I look forward to reading the story because home-grown fundamentalist terrorism is too important an issue to be filed under “evil” and hysterically dismissed in the way that Fox News and its charge-of-the-apoplectic clones would like.

Both fundamentalism and the actions that a small number of fundamentalists take need a more complete understanding. Which is why I’m with the Sydney Morning Herald’s Mark Joseph Stern who reckons “Rolling Stone’s cover of suspected Boston bomber Dzhokhar Tsarnaev is brilliant – deal with it”. Rolling Stone has a long history of serious and edgy journalism, including formative work by Hunter S. Thompson, P.J. O’Rourke and Tom Wolfe. What contemporary subject could be more ripe for genuine journalistic exposition than the making of good-boy-turned-bomber Tsarnaev?

In putting The Bomber on its cover, Rolling Stone draws a disturbing yet obvious parallel between Tsarnaev and the rock ‘n’ roll’s bad boys. The connection is obvious because of the legion of followers devoted to Dzhokhar and convinced of his innocence. Like Jim Morrison in 1969, they reckon he’s persecuted and misunderstood. They can be found with the #FreeJahar hashtag on Twitter and in manifold dark corners of the internet. Word from that parrallel universe has it that the girls a cranky because the picture wasn’t ‘dreamy enough’.

Linda Peach wrote an intriguing introduction to the mostly young, mostly female FreeJahar crowd a few weeks ago. I was not convinced by her favoured explanation which relied on social role theory and ambivalent sexism theory via a weak Prince Charming trope. But that is an argument for another day. As she well explains, the denialist netherworld of FreeJahar throbs with teenage female lust.

My point is that the bad boy mystique of Jim Morrison, Jimi Hendrix and Keith Richards imbued them with sexual magnetism of the most potent kind. This was a dark force, domesticated and sometimes manufactured by later rockers and their publicists. But it made the stars, Rolling Stone and even rock itself what it is.

The crimes that Dzhokhar Tsarnaev has been accused of are so much less commonplace and more dramatic than the darkness at the heart of rock-god sexual magnetism. And I put it that way neither to diminish the far-reaching heinousness of what he and his brother are alleged to have done nor to trivialise the misogyny and abuse that accompanied so much of sex, drugs and rock. But I’m willing to bet that Tsarnaev’s sexual magnetism is not an entirely different species from 1963’s hysteria for the ‘Stones.

If reproductive success could be allocated by virtue by following Baba’s Golden Rule of sex, I’m pretty sure humans would domesticate quite nicely in a few hundred years. And it’s certainly worth a try. But the FreeJahar groundswell convinces me that the odds stack mightily against any chance of long-term success.

  • Disclosure: Baba provided a cover blurb for my book, Sex, Genes & Rock ‘n’ Roll, and, in turn, based some of his show Ingenious Nature on elements of the book. I was delighted to peer-review the full script for the show. I only wish I had been able to see it in New York.

Rob Brooks does not work for, consult to, own shares in or receive funding from any company or organisation that would benefit from this article, and has no relevant affiliations.

The Conversation

This article was originally published at The Conversation.
Read the original article.

Exposure to a novel male during late pregnancy influences subsequent growth of offspring during lactation.

T. Gale, A. B. Gibson, R. C. Brooks, M. Garratt
Journal of Evolutionary Biology. DOI: 10.1111/jeb.12192
In mammals, allocation to reproduction can either be primed or suppressed in relation to cues from other individuals. Some conspecifics (e.g. potential mates) may enhance an individual’s ability to reproduce but others may have a detrimental effect on reproductive success. One widely studied response to conspecific cues, the ‘Bruce effect’, occurs when pregnant females abort their pregnancies after exposure to a novel male. It has been suggested that this response has evolved as a counter-tactic to the threat of infanticide posed by novel males. In some species, like mice, pregnancy termination will only occur if females are exposed to the unfamiliar male during a brief critical period early in pregnancy, which is surprising considering that an unfamiliar male threatens infanticide whenever present, and in particular near to birth. We demonstrate that female mice experiencing novel males during late pregnancy also alter their investment in progeny, but in a more subtle manner than previously observed. Females exposed to an unfamiliar male during late pregnancy give birth to offspring of a comparable weight to those produced by females exposed to the paternal male, but these offspring grow more slowly over lactation. As a consequence, offspring from these females weigh less at weaning. Modification of their growth trajectory, however, allows these offspring to catch up to normal weights by adulthood. Thus, cues of unfamiliar males, and possibly their associated threat of infanticide, can produce more wide-ranging effects on maternal investment than previously recognized.

Cunnilingus-assisted orgasm maybe not such a big mystery

This week I’ve been wrestling with a particularly large writing project which has kept me away from posting in this column. But, staring into my Twitter feed in procrastination, I spotted much outrage about a paper on the adaptive basis of cunnilingus-assisted orgasm. I had to head over to the journal Evolutionary Psychology to take a look.

The authors, Michael N. Pham, Todd K. Shackelford, Yael Sela and Lisa L. M. Welling, all of Oakland University in Michigan report the results of a simple survey they administered to 243 men in committed, heterosexual relationships. They predicted that, in their own words:

among men who perform cunnilingus on their partner, those at greater risk of sperm competition are more likely to perform cunnilingus until their partner achieves orgasm (Prediction 1), and that, among men who ejaculate during penile-vaginal intercourse and whose partner experiences a cunnilingus-assisted orgasm, ejaculation will occur during the brief period in which female orgasm might function to retain sperm (Prediction 2).

It would be too easy to sneer at the rather joyless prose, here and throughout the paper, as some popular commentators have done. And it would also be wrong. We expect scientists working on other less sensitive questions to make clear predictions that avoid imputing value or emotion. And so should it be with predictions about oral sex.

This paper is part of a rich vein of research in Evolutionary Psychology on the function of the female orgasm. In particular, it tests an idea – one enthusiastically championed by Todd Shackleford’s group – that orgasm functions to enhance the chance of conception.

One mechanism by which this could occur is by inducing uterine contractions which draw sperm toward the egg, shortening the distance sperm have to travel. This is one formulation of an old idea, colourfully called the “upsuck hypothesis”. As Mary Roach points out in point six of the video below, evidence supporting “upsuck” is equivocal.

Enjoy Mary Roach’s hilarious talk, reviewing some interesting things she discovered when writing her book on orgasm

Legion studies provide circumstantial evidence consistent with the idea of orgasm as a form of after-the-fact mate choice (“use the sperm of the guy who made you come”). Women with wealthy partners report having more orgasms. More masculine and more attractive men tend to give their female partners more orgasms.

But when would women need to discriminate among men’s ejaculates? When they mate with more than one man over a fertility cycle.

Studies on other animals, particularly insects, suggest that competition among males doesn’t stop at copulation, but continues between the ejaculates when the female mates in reasonably close succession with two or more males. And that females can differentially use the sperm of some males over others.

Studying these questions in humans is, understandably, ethically fraught, and so the evidence for sperm competition is less direct. The size of men’s testes and the volume of their ejaculate suggests that human sperm competition is important but by no means rampant.

That is consistent with the evidence that while humans show an intriguing capacity for monogamy, we are also often enthusiastically promiscuous.

So, returning to the paper in question, what do Pham and colleagues mean when they talk about “men at greater risk of sperm competition”? Did they secretly ask those men’s partners if they had been furtively mating with somebody else? Nope. Turns out their measure, which they rather clinically name “recurrent risk of sperm competition” constitutes “the mean of four variables: how sexually and physically attractive the participant views his partner, and how sexually and physically attractive the participant believes other men view his partner.”

So they asked men, four different ways, how attractive they thought their partners were. Attractive partners, by their logic, are at greater risk of having recently mated with other men.

And they found that men who rated their partners as highly attractive tended more often to have orally brought them to orgasm. Add this to another paper, recently published by Pham and Shackleford showing that men who rate their partners as attractive express greater interest in, and spend more time performing, oral sex on their partner.

Being a defender of evolutionary psychology isn’t always easy. Most research in this field is conceptually interesting, well-replicated and generally robust science. But the stuff that breaks into the news cycle and infests the Twittersphere so often tends to come from the weakest science the field has to offer. And I have to confess I find these studies among the most underwhelming I have recently read.

We biologists tend to forget that talk about sperm competition and cunnilingus-assisted orgasm induces many folks to squirm. It isn’t the squirm factor here that gets my goat.

It’s the way in which the investigator’s favoured hypotheses don’t attract the sceptical self-scrutiny they deserve. And in which alternative ideas aren’t duly considered.

And this includes considering the question from the woman’s point of view. Perhaps gathering data from women. These weaknesses play helplessly into the worst stereotypes that critics of evolutionary psychology deploy to dismiss the biological study of human behaviour.

Have you asked the womenfolk?

Evolutionary explanations for the function of orgasm tend either to see orgasm as a form of mate choice or as a by-product of the male capacity to orgasm at ejaculation. A recent review of the evolutionary literature came down in greater favour of “mate choice” hypothesis than the by-product hypothesis.

The idea that men who view their partners positively might also be more interested in pleasuring them orally doesn’t get the nuanced exploration is probably deserves. Giving and receiving of sexual pleasure is part of the complex social-biological interplay that defines relationships.

Kind men who care enough about their partners to please them sexually may also tend to view them as attractive. Men with attractive partners might work extra-hard to keep them sexually interested. Because those partners have better options should they leave.

My point is not that Pham et al are wrong. Their favoured explanation, cloaked here in the psuedo-objective language of a dry hypothesis, may well prove robust to more critical scrutiny. But there are a wealth of possible alternative explanations, some more likely than the favoured one. I trust the Conversation’s busy commentators will, in typical fashion, identify them all.

One of the things that irritates me about this paper is the way in which the paper considers one explanation among hundreds, finds evidence in support of it, and then ignores the more complex context of the behaviour. Female orgasm and oral sex are indeed rich subjects for study. I would love to know more about why not all women orgasm, why those that do do so in different ways. And why oral sex practices vary so wildly among times, places and individuals.

It is this concession of the complex, social dimensions that concedes the most interesting aspects of behaviour to those who blur it in social constructionist and post-structural mumbo-jumbo.

I wish my evolutionary colleagues would get stuck in to the much more complex social aspects of orgasm and sexual pleasure.

Double standard, much?

Bizarrely, while the function of the female orgasm gets treated as a mystery, the male orgasm seldom gets an equal workout (cue whingeing from both sides of gender political spectrum). Because male orgasm so often accompanies ejaculation, should we think of it as a mere reward for depositing sperm, motivating men to become rampant sowers-of-oats?

Likewise, I don’t see a lot of head-scratching about the functions of fellatio. And other practices that cause seed to be spilled in places other than a vagina connected to an ovulating uterus. We leave the ultraconservative nutbags to worry about these questions. So many of us stop uncritically at the assertion that sex, for men, is fun.

Why is sex fun? The answer, to so many of us, is obvious. But when Jared Diamond asked this question he exposed many far more intriguing questions that lurk beneath.

Anyone can conjure superficial answers to questions like “why do women have orgasms?”, “why don’t all women have orgasms?”, “why do men orgasm when they ejaculate” and “what is the function of oral sex?”. Good answers based on solid science are much, much harder to come by.

But that shouldn’t stop us from trying.

Rob Brooks does not work for, consult to, own shares in or receive funding from any company or organisation that would benefit from this article, and has no relevant affiliations.

The Conversation

This article was originally published at The Conversation.
Read the original article.