Why women eat salads on dates

Is she resentful?

I have a friend who only orders salads when she goes out on a date. Me, I’d order the pasta and make sure to leave room for dessert. Turns out I’m unusual that way.

According to the latest study at McMaster University, women consume far fewer calories in the presence of a man (or men) than when eating alone or with another woman. Of over 450 people observed in a cafeteria setting, only the women revealed different consumption habits around the opposite sex.

What I was oblivious to when dating is the fact that what you eat, and how much, can affect impressions of your habits, world-views, social appeal, and attractiveness. According to the authors, psychologists Meredith Young and her colleagues:

1. In [groups of two], women selected foods with lower caloric value if their companion was male than if with another woman, whereas men’s choices were not affected by partner’s sex.

2. In our study, women’s total calories were not just reduced in the presence of a male, but also decreased further as a function of the number of male companions (and tended to show a reverse effect of female companions).

3. Women, in particular, adjust their eating to accord with consumption stereotypes, specifically that smaller eaters are viewed more favorably. The women we observed adjusted food selection not so as to match men, but perhaps in accordance with beliefs about what men find attractive.

Is a lusty appetite really less attractive?

How it’s possible to be too nice

A few weeks ago, my friend G. went out on a date with a man she met online. She had liked the guys’s profile: mid-thirties, lawyer, yogi, middle child (like herself), vegetarian. He was cute, too, with green eyes and a boyish grin. In his profile photo he included a shot of himself hugging his niece. And when G. met him, he hugged her, too — a great bear hug. He held the door open for her when they went to the restaurant and picked up the check at the end of the meal. All this she liked, but she said certain things about him annoyed her. When pressed, she said sheepishly: “I know this sounds weird, but he was just too nice.”

G.’s date not only opened doors for her, but also for the women behind her. He struck up conversation with the people at the next table and helped them get the waitress’s attention. Strolling together in the park after dinner, she caught him smiling at people who passed.

That’s odd, I thought. Studies show that kindness is one of the top qualities that men and women seek in a partner. But then I found a new study by University of Santa Barbara evolutionary psychologists Aaron Lukaszewskia and James Roney that offers a little more nuance.

Yes, the psychologists found: people prefer partners who are kind, altruistic, and trustworthy. In fact, people desire as kind a mate as possible. But what most studies fail to take into account is to whom the kindness is directed. Most people agree that prospective partners must be kind and generous with their companions, friends, and family. But what about people in the larger social context?

Lukaszewskia and Roney embarked on their investigation by asking nearly 60 women and more than 70 men to rate various personality traits in their ideal partner: kindness, trustworthiness, and dominance. Do you want your ideal partner to be less, equal, or more (kind, trustworthy, dominant) than the average man/woman? Do you want you partner to be less, equal or more (kind, trustworthy, dominant) than the average with other men or other women?

Here are the results:

Both sexes preferred very high levels of kindness and trustworthiness only when considering behaviors directed toward self or close friends and family, and much lower levels of these traits when considering behaviors directed toward other classes of individuals. In fact, people may actively prefer that their partners not be too kind or too trustworthy toward people who are not companions, friends, or family.

My friend G. hated it when her date expressed as much kindness with strangers as with her. A turn-off, she said. Men apparently don’t like it either. Nice guys and gals appear to finish last when they’re too nice to everyone.

Women preferred higher levels of dominance when considering behaviors directed toward other men than when considering behaviors directed toward self. Although not predicted in advance, men’s dominance preferences showed the same pattern as women’s preferences, with higher levels of dominance preferred when considering behaviors directed toward other women than when considering behaviors directed toward self.

Curiously, many studies suggest that women value kindness over dominance in long-term relationships, but this only applies to their partner’s dominance in a broader social context. Men also prefer women who are dominant among other women (but not dominant in the context of the relationship). As an interesting side note, the evolutionary psychologists suggest that men in ancestral environments may have benefited from having partners who were dominant within female status hierarchies (offspring more likely to survive).

Going on what G. told me about her date, I suspect there’s another explanation for why excessive kindness to others can be a turn-off in a partner. We all want to feel special, sought out. As other studies I’ve described in BLONDES have shown, homing in on one person and making that one person feel unique and exemplary is key. G.’s date may have been an extremely nice guy, but he didn’t make her feel special. Who knows how he’d be as a boyfriend — would his eye wander?

He who loves all may not love one. It’s as George Orwell said: “Love means nothing if it does not mean loving one person more than others.”

What machines teach us about how we flirt

I’ve always been a fan of the MIT Media Lab, and in BLONDES I write about Media Lab director Alex Pentland’s development of a machine that tracks “vocal body language” — pitch, speed, the space between words, and so on. Tested in a speed dating study, the machine had an impressive accuracy rate. About 70 percent of the time it could predict whether a man and woman was interested in each other, and whether they’d say yes to a second date.

Now it turns out that researchers at Stanford are following suit, in what may someday be the next big iPhone app.

Computer scientist Rajesh Ranganath and his colleagues developed a “flirtation-detection machine” that — based on prosodic, dialogue, and lexical clues — can detect a speaker’s intent to flirt with up to 71.5 percent accuracy. (In contrast, men were only 56.2 percent accurate when assessing if their date was flirting with them, and women were only 62.2 percent accurate.) Results were derived by testing the machine’s analysis against the self-reported intentions and perceptions of men and women on a speed date.

Without going into the technical details of the study, here are a few of the findings:

1. [When flirting],men ask more questions, and use more “you” and “we.” They laugh more, and use more sexual, anger, and negative emotional words. Prosodically they speak faster, with higher pitch, but quieter [softer voice] (lower intensity min).

2. [When flirting], women use more “I” and less “we”; men use more “we” and “you”. Men labeled as flirting are softer, but women labeled as flirting are not. Women who say they are flirting have a much expanded pitch range (lower pitch min, higher pitch max), laugh more, use more “I” and “well,” use repair questions (Excuse me?) but not other kinds of questions, use more sexual terms, use far less appreciations (Wow, That’s true, Oh, great) and backchannels (Uh-huh., Yeah., Right., Oh, okay.), and use fewer, longer turns, with more words in general [than do men].

3. Both genders convey intended flirtation by laughing more, speaking faster, and using higher pitch. However, we do find gender differences; men ask more questions when they say they are flirting, women ask fewer, although they do use more repair questions, while men do not.

Interestingly, the device was able to predict flirtation in men with greater accuracy than in women (79.5 percent versus 68.0 percent). In BLONDES I write about evolution and men’s overperception bias; essentially, guys are wired to think women are into them when they are not. I wonder if this is also true of the machines men make.

Foot-in-the-door as a pickup technique

French psychologist Nicolas Gueguen is fun. He’s the guy who asks the pressing questions we’d all like answered, whether we admit it or not: Does makeup really make a woman more attractive to men?; Are dog owners more likely to get dates?; How much does cup size really matter?; and How does priming men to think about love change their behavior?

And now Gueguen strikes again, this time with a study on courtship and “foot-in-the-door-technique.” The latter is an actual term in psychology. “Foot in the door” is a compliance tactic in which an initial, small difficult-to-turn-down request is made (as in a solicitor asking passers-by on the street for their signature). Once people acquiesce to an easy request, they are likelier to agree to a larger request (to donate money, time, etc.). Kids seem to implicitly know the foot-in-the-door effect, as when they ask for a small treat, followed immediately by a request for a larger one.

But what about men looking for love (or sex)?

Gueguen wanted to know if the foot-in-the-door technique would work in a pick-up context, so he recruited a nice-looking guy in his twenties to solicit young, hot women in the street. Over a series of days the man approached 360 different ladies, and asked them if they’d like to have a drink with him. Some of the time he approached them, greeted them, and made the drink offer right away. In the foot-in-the-door condition, however, he asked them for directions or requested a light for his cigarette before inviting them to have a drink with him.

Turns out, the technique works. Women were significantly more likely to say yes to a drink with the guy if he made a minor request immediately beforehand. That’s how foot-in-the-door works, by fostering compliance. It’s easier to say no when the no hasn’t been preceded by a yes. (Incidentally, it’s also more difficult to say no after nodding your head.)

Of course, for most men the aim is to get much more than a foot in the door. For that, I suspect the actual nature of the second, larger request counts a lot. Ask too much, guys, and you’ll get a door-in-the-face.

The science of gaydar

Given at least 1/20th of a second to look at a man, you can probably guess whether he’s gay — and be correct at least 70 percent of the time. Remarkably, your first split-second assessment would be as accurate as your impression after a full minute.

That was the case, at least, in a study by Tufts University psychologists Nalini Ambady and Nicholas Rule when they asked male and female judges to guess the sexual orientation of 90 faces of gay and straight men (without facial hair or piercings). Regardless of their own sexual orientation, the judges were astoundingly swift and accurate when it came to identifying most men’s sexual orientation. (Women’s faces weren’t tested.)

But the problem with gaydar — a contraction of “gay” and “radar” — is that identifying gay men and lesbians based on physical qualities alone isn’t always reliable. Despite the high accuracy rate for most faces, several yielded no clue of sexual orientation and were consistently misjudged. And when the judges were right, it was tough to pinpoint what clued them in. Was it the set of an expression? The hairstyle, the lips, the lower jaw? The eyes? Nevertheless, the results were surprising because many gays and lesbians attribute their own gaydar to behavioral cues such as the way someone looks at them — a sliding glance or the hint of a wink — or certain postures, gestures, facial expressions, and ways of speaking. As for straight women having gaydar, it might be evolutionarily advantageous — after all, it’s helpful to know who is a potential mate and who is not.

Stripped of cultural influences, there aren’t clear-cut, consistent physical distinctions that would trigger gaydar. Not that researchers haven’t found some very general biological differences between straights and gays.

As I detail in BLONDES:

* Prenatal testosterone levels, which are linked to sexual orientation, also influence traits such as finger ratios. Gay men’s ring and index fingers (of the right hand especially) are more likely to be the same length, like those of straight women, whereas a greater number of straight men have a ring finger that’s longer than their index finger. Women who identify themselves as “butch” lesbians are much more likely than “femme” lesbians or straight women to have a low digit ratio (ring finger longer than index finger) due to higher levels of prenatal testosterone.

* Depending upon the study (one here), gay men have a 34-82 percent greater chance of being left-handed than straight men (note: not all studies detect a bias), and lesbians are up to twice as likely to be lefties than straight women. Bear in mind that even though a gay man or lesbian has a higher chance of being left-handed, the majority of lefties are straight.

* Sniffing t-shirts of gays and straights, gay men prefer the odor of other gay men more than straights of either gender do. (Lesbians generally like the natural smell of other lesbians, straight women, and even straight men.)

* Gay men’s hair whorl (direction of scalp hair rotation) is more likely to be counterclockwise than that of straights. Nearly 30 percent of a sample of gay men had hair whorls that rotate counterclockwise, compared to fewer than 10 percent in a mixed group of men and women.

* A man’s gait might be another clue — in one study, judges identified gay men by their walks with about 60 percent accuracy. The reason is that some gay men have lower waist -to-hip ratios (larger hips compared to waist) than the average straight guy.

None of these traits proves a person is gay or lesbian, nor can their absence prove a person is straight. They’re just trends. Yes, gaydar works, although it’s as much an art as a science.

But someday, if MIT’s Project Gaydar goes as expected, identifying who’s gay may be mere computation.

No eyebrows = you’re less recognizable

Evolution has done to our profiles what glaciers do to mountains. Gone is the jutting jaw. Washed away is the bulging brow ridge. Our faces are relatively flat compared to what they once were. This means there’s not much to look at to get your bearings. According to a study by Javid Sadr and his colleagues at MIT, eyebrows are a crucial part of facial identification. The behavioral neuroscientists discovered that faces without eyebrows are like land without landmarks.

The study: Volunteers were asked to identify fifty famous faces, including that of former U.S. president Richard Nixon and actor Winona Ryder. The photos were digitally altered and shown either without eyebrows or without eyes. When celebrities lacked eyes, subjects could recognize them nearly 60 percent of the time. However, when celebrities lacked eyebrows, subjects recognized them only 46 percent of time.

The lesson: eyebrows are crucial to your identity — they’re at least as important as your eyes, if not more so. If you put colored contacts in your eyes, pumped collagen into your lips, or put on a pair of funky sunglasses, people would probably still recognize you easily. But try shaving off your eyebrows. Chances are that everyone will say they didn’t recognize you at first glance.

As Sadr points out, eyebrows pop out against the backdrop of your face — and for that reason not only identify who you are but how you’re feeling. Along with the lips, they may in fact be the most expressive part of your body. The single raised eyebrow is a universal sign of skepticism, and the dual raised eyebrow a sign of surprise. Think about it — entire Charlie Chaplin movies are spoken in the language of brows.

The shape of your eyebrows also says, in a glance, a lot about your age and other characteristics. Bushy, gnarly, salt-and-pepper brows: old, powerful men. Thin, graceful arcs: young, stylish women. Sparse, light brows: childlike. When waxed and tweezed, the brow is a sign of good grooming.

Eyebrows sometimes meet each other halfway across the bridge of the nose, especially on men, to form a “monobrow,” which resembles the vanished browridge of our primate ancestors. Distinctive? Yes, and also brow-raising.

Are men in pinstripes more marriage-worthy?

There’s a new twist on that classic McDonald’s experiment, the one in which there are two photos of a guy; in the first he’s dressed in a Mickey D’s uniform and in the second he looks like a banker. Women are asked to judge the man’s physical attractiveness and — surprise! — he gets much higher attractiveness ratings when he’s wearing a suit.

In the current study by evolutionary psychologist Murray Millar at the University of Nevada, women behaved similarly. This time, 123 female judges were shown photos of three men seeking a partner. A description accompanied the photo of each man, containing general biographical information (e.g. place of birth, food preferences), a statement about what type of relationship he was seeking (long-term or short-term), and his profession, which was either high-status (doctor, banker, lawyer) or low-status (salesman, janitor).

No shocks here: As Millar suspected, women, when primed to think about a long-term relationship, found men more attractive when they were described as having a high-status profession than a low-status one. For a fling, the ladies gave men more-or-less equal attractiveness ratings regardless of profession. These results, Millar concluded, are in keeping with the evolutionary argument that women have different mating strategies. For long-term relationships, women implicitly place more value on social status and resources that may benefit her child. For short-term relationships, women place more value on cues of genetic value such as physical attractiveness. In the latter condition, it doesn’t matter so much if he cleans toilets or flips burgers for a living. They’re lovin’ it.

But it’s not always so simple, as I describe in BLONDES. Hormonal cycles may subtly push or pull us in unexpected directions. Don’t forget the UCLA study in which women who were in their peak fertile window (around ovulation) found poor creative men more attractive than rich boring ones, at least in the short term. As evolutionary psychologists suggest, mating isn’t always binary. That is, some women may pursue more than one strategy at once: marry a stable office worker and have curiously-timed flings with hunky down-and-out artists (or burger flippers).

Perceptions may also shift. As women becoming more economically independent, they may find high-dominance males less desirable in a marriage context. Better, perhaps, to have a man who’s around more to change diapers. Even now, given the cause of the current recession, pinstripes might not be so marriage-worthy.

PORN: pastime or peril?

Today I’d like to introduce a guest blogger, Duana Welch, Ph.D., author of Love Science, a fabulous relationship advice column that bases its advice in social science research rather than opinion. Check out Duana’s blog at http://www.lovesciencemedia.com/.

Sorry; no pictures. But you really are here for the articles…right? Right?!?

And in that spirit, Wise Readers, here are two notes your cohorts sent regarding pornography and marital happiness—the first from a man, the second from a woman:

“I think that happiness, including sexual, can be satisfied in many ways both with and without influences outside of the marital relationship. Unfortunately, one answer to what the effects of porn are on marital well-being is, “It depends.” There is such a huge dynamic involved. Full disclosure: I have looked at boobies on the Internet. I love my wife and in no way think that those other boobies have changed the way I feel about her.” –Sam

“I am already pretty insecure about my own sexiness quotient, and I think feeling sexy to your mate is key to being able to open up and fulfill both of your sexual and emotional desires. Knowing that my mate needs to fill his thrill with external stimulants does not make me more inclined to open up more — in fact it has the opposite effect. On the other hand, it is probably all in the approach — light porn shared between secure partners might serve to rev the engine. But porn found stashed on the computer or behind t-shirts in the closet is not the best way to ignite my flame. Unless it’s the flame behind my eyes…” –Gina

So who’s right? Is porn a mere pastime, a marital peril, or some combination of the two? Certainly, the question is not an idle one; porn outsells all other forms of media combined every year, and the National Research Council reports that in the USA, porn is a bigger money-maker than all pro sports together. Recently, Utah’s residents were reported to be America’s top Internet-porn “end users” (pun intended), with much hoopla ensuing about What It All Means.

Happily for us, for almost 30 years, well-regarded researchers such as Dr. Neil Malamuth and Dr. Ed Donnerstein have studied porn’s effects. Experiments abound; conclusive, cause-based answers—no wussy mere correlations here!—exist.

And the first conclusion is: Viewing porn *causes* increased male violence against women and increased male acceptance of violence against women—IF and only if the porn viewed is violent. In the typical rape porn script, women who are initially unwilling appear to become enthusiastic participants in their degradation, ultimately screaming out for more. In these experiments, men are randomly assigned to view violent porn or non-violent porn or non-porn, and are then given opportunities to behave so that the researchers can compare the groups’ resulting attitudes and behaviors. It is now well-documented that men who experience violent porn are more accepting of such violence, believe sexual violence is not such a big deal, rate injuries real women have sustained as not being severe, recommend 50% lighter prison sentences for real rapists, and –most compelling—they actually harm women. For example, in one such experiment by Donnerstein, men who viewed a violent porn film gave higher shocks to a woman who made a learning error than did the men who viewed a non-violent porn or non-porn movie (the violent-porn viewers also gave much lower shocks to a man who made a learning mistake). The men were not actually administering shocks; but they fully believed that they were.

Yet most of the porn consumed today is non-violent; everyone in the images is portrayed as ready, willing, able, and of legal age. So what are the effects there? First, the good news: Non-violent porn viewing among non-addicted observers does not cause mates to stop loving one another, nor to actively harm one another. If a spouse is devoting a lot of time and money to porn consumption, that is taking away from the couple’s bond–but that can be said of any activity with an inappropriate focus of time, dollars and energy.

On the other hand, you can forget this rationale: “Honey, I actually want you more if I watch porn!” Although porn can have a very temporary effect of making men want to have sex with the nearest acceptable person—such as their spouse—the longer-term impact is not positive for the marital bond. Simply put, porn makes men less excited by and attracted to their mates. Experiments by Dr. Douglas T. Kenrick , Dr. Dolf Zillman and others show that men who have recently viewed porn rate their own partners as substantially less desirable and attractive than men who watch non-porn material. (To a much lesser degree, this is true of watching gorgeous creatures generally; even men who have recently seen an episode of “Charlie’s [fully-clothed] Angels” rate photos of a normal, unknown woman as plain…plain.)

We’ve paid a lot of attention to men’s perceptions; they buy and watch the vast majority of the porn, and that’s where most of the research has focused. What of women’s post-porno experience? In a nutshell, women are more physically turned on by porn in the moment than they admit; women worry about their mates finding them less appealing after the women have seen porn; women see themselves as less desirable after watching porn; and women flatly reject the idea that they would want to be raped.

So, Sam and Gina: You’re both partly right. Sam, you’re almost certainly not less in love with your wife for having seen a few extra boobies, although unless hers are truly supreme, you may find yourself less attracted to hers than before. And Gina, if your physique compares unfavorably to the perfect pay-per-view bodies, you’re feeling appropriately threatened vis-à-vis your desirableness to your mate. And both of you: In no case is porn actually helping your marriage.

What’s a guy or girl to do? Obviously, avoid the violent stuff. As for non-violent porn, it’s no marital happiness promoter, but it’s not necessarily the home-wrecker it’s been cast as, either.

Cheers,
Duana

Duana C. Welch, Ph.D., is the author of blog Love Science: Research-based relationship advice for everyone (www.LoveScienceMedia.com). Although many relationship advice columns exist, Love Science is the only one that presents not only what to do and how to do it–but the science and research behind the advice. Published free bi-weekly, Love Science is also Amazon.com’s best-selling relationship and behavioral science blog for Kindle. Feel free to Ask Duana *your* question at Duana@LoveScienceMedia.com.

All material copyrighted by Duana C. Welch, Ph.D., 2009

Are women more interested in men who are taken?

If you believe that all the good men are already taken, doesn’t it follow that you’d be more interested in a married (or otherwise engaged) guy? It’s been found to be true of other female animals — even fish and birds — they all prefer to “poach” males already chosen by other females. And I describe in BLONDES, studies have found that men who are in the company of an attractive woman (especially if they’re smiling at him) are more desirable to female judges.

But are women more likely to chase that guy if he’s already taken?

Psychologists at the University of Oklahoma wanted to know, so they recruited nearly 200 heterosexual men and women, some of whom were single and others who were in relationships. Told only that they were participating in a study on attraction, they were shown a photo of an opposite-sex stranger and answered questions about their attraction to that person: How likely would you show interest? How likely would you be to initiate conversation? How likely would you be to initiate a romantic relationship with this person? The psychologists also attached a relationship status to the person in the photo: either single or in a relationship.

Turns out the relationship status made a tremendous difference — but only when it comes to women choosing men, and not the other way around. As expected, women in relationships were less attracted to the stranger than single women were, regardless of the man’s relationship status. But here’s the interesting result: single women were more attracted to the man, and more likely to initiate a relationship with him, when told he was in a relationship than when told he was single. According to the psychologists, an attached man signals desirable resources and a willingness to commit to family life. He’s been tested, “pre-screened.” Simply put, commitment makes men more attractive.

As for men, a woman’s relationship status, at least in this study, had little effect on her attractiveness Single men were slightly (although not significantly) more attracted to the woman when told she was single. Attached men were slightly (although not significantly) more attracted to a woman when told she was attached.

Of course, bear in mind that this study is based on photos and is hypothetical. I suspect a man’s partner has some influence over whether a single woman dares move in on her territory. Is she beautiful? Is she the jealous type? And what happens after a divorce or break-up? Is a divorced man more attractive than one who never committed?

Are Americans more loving?

I love the large cross-cultural surveys done by evolutionary psychologist David Schmitt and his colleagues at Bradley University. His latest adds evidence to the conviction that love is universal. Repeat: love is universal. To be universal, there must be a evolutionary reason — in other words, it must help our species to perpetuate somehow. As Schmitt explains:

Love can rivet our attention to a single mate, instigate the process of romantic flirtation, lead to systematic patterns of courtship behavior, and on occasion culminate in marriage. Love helps parents bond in healthy ways with newborn offspring, leads to informative adolescent infatuations before more serious romantic pursuits, and serves as a social glue for functional interchanges of support amongst family and friends.

But even if love is universal, there are some very interesting cultural distinctions that emerge in the study. Here are a few outcomes/insights derived from the answers of 15,234 participants from 48 nations:

Nationality affects emotional investment, an indicator of love. As measured by an Emotional Investment Scale, countries in which people scored highest are the United States, Slovenia, and Cyprus. Low-scoring nations were Tanzania, Hong Kong, and Japan.

Focusing on men alone, the countries with the most emotionally invested males are the United States, Brazil, Portugal, Argentina, Philippines, and Greece.

The countries with the most emotionally invested women are Slovenia, the United States, Malta, Cyprus, Australia, and Argentina.

In almost every country, women reported higher levels of emotional investment than did men. But there are a few notable exceptions: In Bolivia, men and women were identical in their average levels of Emotional Investment, and Malaysia, men scored higher than women (though not significantly so). The researchers suggest there is something restricting women’s reporting of their romantic investment in these two cultures.

Oddly, sex differences in emotional Investment were larger in nations with high gender equality (e.g., Switzerland, Australia, and Germany) and were smaller in nations with low gender equality (e.g., Turkey, South Korea, and Bolivia). The researchers claim: “What appears to be happening is that greater gender equality is associated with higher Emotional Investment among both men and women, but the accentuating effects of gender equality on Emotional Investment are greater among women, leading to larger levels of the naturally-occurring sex difference in Emotional Investment.”

Stress reduces emotional investment. In cultures with high stress (e.g., Bolivia, Indonesia, and Malaysia), levels of Emotional Investment were significantly lower, especially among women. High national levels of stress (Infant Mortality rates, Childhood Malnutrition rates, and the Pathogen Stress experienced in local environments) —were also linked to lower levels of Emotional Investment. This is predicted by evolutionary theory: harsh conditions lead people to develop insecure attachment levels that result in lower emotional investment.

Emotional investment doesn’t lead to higher fertility rates.To the contrary: countries with lower emotional investment levels among women were related to higher fertility levels.

Countries scoring high in emotional investment don’t have stronger marriages. To the contrary: national levels of emotional investment were positively correlated with divorce rate, unrestricted sociosexuality, short-term mating interests, and the tendency to engage in short-term mate poaching (i.e., stealing someone else’s partner for a short-term sexual affair)

Emotional investment is linked with commitment, but there are nationwide exceptions. Individuals from North America who reported more unrestricted sociosexuality reported lower levels of emotional investment. Similar results were observed within the world regions of South America, Eastern Europe, and Oceania. However, unrestricted sociosexual individuals from South/Southeast Asia and East Asia reported higher levels of emotional investment. Moreover, individuals from Africa who were interested in short-term mating reported significantly higher levels of emotional investment.

Emotional investment peaks when dating one person. It’s somewhat lower among those who are living with someone, married, or currently single (in that order); and is significantly lower than that among those who have never had sex.

Schmitt admits that people from different cultures may express emotional investment differently (have different response biases) and in ways hard to quantify on a standardized scale. Moreover, the questions were written in English and translated into the native languages of the participants. Could this possibly bias the U.S. results — or are Americans really more loving?

(My book, BLONDES, provides a more detailed description of some of Schmitt’s fascinating work with the International Sexuality Description Project.)

Night owls have more lovers

Early birds may get worms but not chicks. That is, according a recent study by Davide Piffer at the University of Pisa, the mean number of sexual partners for morning-oriented men was 3.6 versus 16.3 for evening-oriented men. This means that guys who are night owls have about four times as many sexual partners as morning birds.

Drawing on evolutionary psychology, Piffer offers a few theories:

1.) Throughout human history social activities have taken place at night. (In fact >60 percent of the people Piffer polled met their latest partner in the evening or night.) The evening is commonly reserved for courtship activity — dancing, drinking, having sex. Over time, the male night owl attends more social events, meets more women, and has more sex.

2.) “Eveningness” is a sexually dimorphic trait. Across cultures, “more males than females stay up late at night (due to biological differences involving the timing of peak melatonin levels). Piffer speculates that men evolved to stay up late because, in the deep past, the most reproductively successful males were night owls and they passed along their genes to subsequent generations. In terms of Darwinian sexual selection, evening orientation benefits males more because it gives them an increased opportunity to acquire multiple lovers — all at one go, or over time. Women, however, don’t achieve greater reproductive success by having sex with more men (it only takes one to get pregnant), which is why fewer women are evening-oriented. Men with an evening orientation have a competitive advantage over men with a morning orientation.

3.) Evening-orientation, Piffer speculates, may also be a direct product of sexual selection. That is, women may actively choose night owls over morning birds. Piffer draws on the “cads-versus-dads” theory; that is, women often go for bad boys, especially at a certain stage of life, and men who stay up into the night are likelier to fall into this category.

4.) Being a night owl may also be a form of “handicap signaling.” Staying up late at night (possibly drinking and smoking) can take a toll on one’s health. Only a man who is fit and healthy would be able to compensate for his lifestyle. Assuming a man seems unaffected by little sleep, his evening orientation indicates a strong constitution — a sexy quality.

Mind you, Piffer’s theories are allextremely speculative (but fun!). Of course there are many unanswered questions: By nature, is there something about a night bird’s personality that makes him more promiscuous than a morning bird — or is it only that he has more opportunities to meet women? Do night owls in all cultures get more sex? The study took place in Italy — it would be interesting to repeat the same experiment in non-Western cultures.

At least this may explain the otherwise inexplicable female obsession with vampires.

Rechanneling sexual arousal?

Scientists know exactly how to mediate sexual attraction between mice. Introduce males to females, and the brain region known as the anterior cingulate cortex (ACC) is activated. A new study has found that he neurons in the ACC are “fed” by a fusion of glutamate when a mouse is sexually aroused. Shut down the ACC with a sly drug and the result is a sudden loss of sexual interest. The drug used in the study was muscimol, the major psychoactive ingredient in some mushrooms such as Altamaria, and in mice it reduced sexual attraction within ten minutes of injection and lasted for about a half hour.

This is interesting because human attraction is also mediated by the ACC (as I describe in a previous post and in BLONDES). Researchers speculate the the ACC is involved in feelings of pain and pleasure and the evaluation of risk and reward. ACC activation affects our emotional state, leading to sexual behavior.

Is it possible to shut down our ACC with a drug such as muscimol (or a different drug without psychoactive side effects), and would it also temporarily make us asexual?

Bear in mind that what works in mice might backfire in humans. We may find that desire can overpower an addled ACC — there’s more than way to turn us on. For instance, sexual arousal of sorts is known to occur in a muscimol-induced dream state — although it often translates into a sort of cosmic awe. Some people apparently can have sex on psychedelics (although most popular ones are psylocybin-based, not muscimol); many can not. (Annie Sprinkle says that when she takes mushrooms (psylocybin) she doesn’t want to make love in a traditional sense, but found they can “deepen a relationship/”). It’s out-of-body sex. It transcends sexual arousal.

To get a real sense of the complexity of human sexual arousal we’d need human subjects — but even if volunteers are willing, certain experiments are unlikely to fly with ethics boards. Which brings us back to muscimolized mice, who, unbeknownst to us, may also be experiencing a sort of transcendental erotic phantasmagoria.

But a mouse couldn’t describe it as Annie Sprinkle does:

[Sex on psychedelics] was not about bodies coming together for physical sex, but about circulating sexual energy, which was everywhere and available just for the asking. I could tap into it just by tuning in and saying “yes.” I realized that everything was sexual/ sensual–that even all my little cells were all having sex. Sex was both microscopic and enormous.

Does “stress sweat” make you more compassionate?

Pheromones fascinate me, and not only the ones that mediate sexual attraction.

Several months ago I wrote a post about a study that suggests that airborne chemical signals also mediate stress and fear. Known as alarm pheromones, these chemicals are found in sweat and saliva. In that experiment, sweat from skydivers (collected from pads in their armpits) activated anxiety circuits in the brains of people who sniffed those pads later on. The fascinating theory: Emotions can be communicated by smell. It happens unconsciously.

That was just one study, and naysayers are quick to point out that a solitary experiment doth not prove human pheromones are real. But now there’s further proof.

Researchers at the Universities of Dusseldorf and Kiel in Germany recently published the results of study based on the sweat smells of 49 stressed-out students after a.) taking a final oral exam (stress sweat) and b.) exercising (sport sweat). Sniffing the pads that had been in students’ armpits, volunteers often couldn’t detect an actual odor. Nor could they tell whether they were smelling stress sweat and sport sweat. But it turns out that an area of their brains detected the difference. Only stress sweat — and not sport sweat — triggered brain activity in areas involved in the processing of social emotional stimuli (fusiform gyrus), and empathetic feelings (insula), attention (thalamus).

The implications are fascinating. Is stress contagious? In an emergency situation, it makes sense that we’re “wired” to perceive and respond to the stress of others. An odor that induces attention and anxiety may help a group to focus together or synchronize a fight-or-flight response.

It’s particularly interesting that neural circuits associated with empathy — not just attention — were activated. Are we naturally empathetic creatures? Then again, there’s no proof that the volunteers actually felt more understanding and compassionate when smelling stress sweat even if their brains go through some of the motions. I suspect empathy is context-dependent. Further experiments should look into whether volunteers really are more empathetic (more willing to help a person in distress, for instance) after smelling stress sweat compared to sport sweat. If so, this would be further proof that stress sweat is an alarm pheromone, which, by definition, changes the way we behave after we inhale it.

A thought: Could stress sweat induce compassion in autistic people?

And another thought: If feelings have smells, is happiness also inhalable, communicable?

Are pheromones why the rhythm method doesn’t work?

For women not trying to get pregnant, life should be easy. Conception can only happen in the 12-24 hours after ovulation. Sure, sperm may last as many as 3-4 days in the genital tract, hanging around for the egg to arrive. But you’d think not having sex during the 4-5-day window would be sufficient to avoid mishaps. That’s what the rhythm method is — a natural form of birth control that relies on abstinence on fertile days.

But slips happen even among the most careful practitioners of the rhythm method. Some of this may have to do with women not keeping perfect track of their menstrual cycles or having naturally irregular cycles. (I discuss in BLONDES the evolutionary reasons why ovulation is hidden to both women and their partners.) The failure rate for rhythm method is 25 percent each year (with a perfect-use rate of 9 percent).

Why so high?

Another reason could be pheromones. The latest issue of my favorite journal, Medical Hypotheses, includes a submission that suggests that pheromones from men may cause an early ovulation in women. By invoking an early release of the egg — in advance of the expected fertile window — chances of fertilization are higher. As I mention in BLONDES, studies have the found that androstadienone, a testosterone-related compound found in men’s sweat, semen, and saliva, increases the amount of luteinizing hormone in women, which thereby triggering ovulation. It’s possible that high-testosterone men may be likelier to have this effect on their lovers. Their sweat smell alone may do the trick.

As I mentioned in an earlier post, there are other properties in semen that may also trigger early ovulation. For instance, seminal fluid contains follicle stimulating hormone (FSH) and luteinizing hormone (LH), which may coax the ovary to release an egg.

Despite the high failure rate, the Roman Catholic Chruch continues to promote the rhythm method, now renamed natural family planning (adding cervical mucus and temperature data to the regimen). Problem is, we don’t live in a clockwork universe, nor do we have clockwork bodies.

“Blondes” in Elle

Nice mention of BLONDES in ELLE magazine. Johanna Cox interviewed me for her fun article and mentioned the Hungarian hair-length study I describe in the book. A previous article also draws on some of the lighter topics in the book.

Do beauties inspire higher sperm counts?

Not all orgasms are created equal. For instance, intercourse orgasms are known to trump masturbatory ones, as evidenced by the amount of dopamine and prolactin produced. For men, sexual excitement produces higher sperm counts. As I recount in BLONDES, men who felt jealous or threatened by the possibility of a cheating partner had higher sperm counts than men who did not. The same is also true of male porn-watchers masturbating to a threesome. When guys watched two men attending to one woman, they had higher sperm counts than when watching one-on-one sex.

Sperm competition is the reason, according to the notorious British biologists Baker & Bellis. Men produce more copious, higher quality semen in situations in which those sperm might compete with rival sperm from other males.

And now there’s more — speculation that beautiful women also inspire men to have better quality sperm.

Female beauty has been found to enhance male sperm quality in other species. The latest evidence comes from a study led by Oxford biologist Charlie Cornwallis on Gallus gallus, a species of bird. Cornwallis and his colleagues discovered that the comelier the chick — e.g., plump with an elaborate comb — the better the quality her partner’s sperm (more motile, higher velocity, with a higher sperm count). Interestingly, this was true of dominant males but not subordinate ones, who appeared to put everything they had into every copulation. From Cornwallis’ perspective, the most fit males invest their best loads in the most reproductively fit females.

No study has yet proven that the same is true in humans — it’s not exactly ethical to recruit a guy to have sex with both a beauty and a plain Jane and then compare the aftermath. A beauty bias that affects sperm count may be true only in a wildly polygamous species, which humans are not.

Even so, this theory applied to humans doesn’t sound so controversial if you think about it — after all, sperm counts in men are associated with sexual excitement. Beauty can spark frisson. Even more exciting to ponder is how in practice an alpha male would make a larger reproductive investment in the most desirable mate. How does a Hugh Hefner decide? And wouldn’t it be ironic if this were true?

PsyBlog Top 40

PsyBlog, a superb psychology blog in its own right, named this blog as one of the “40 Superb Psychology Blogs.” Click here to see the others on the list. Thank you, Psyblog!

Blatant works best when picking up men

In BLONDES I wrote about the pick-up lines men use to strike up conversation with women. Direct compliments were bad, sexual come-ons worse. The most effective lines involved those that suggested social status (“This drink’s on me; I know the owner.”) and kindness (“Let me help you get to the front of the line”) or culture and wealth (“I like your Versace sunglasses. I’ve got a pair too.”)

But given that women also approach men, what pick-up lines should women use?

The answer is direct no-nonsense lines, according to a recent study led by Joel Wade at Bucknell University. Wade and his colleagues asked 40 female undergrads which lines they’d use to pick up a guy, and how likely they’d use those lines in a real-life situation. More than 30 men were than asked to evaluate the lines.

The results:

“Hey, want to meet up later tonight?”
“Do you have a girlfriend?”
“I like your hair”
“Give me a call – here’s my number”

trumped the more subtle
“Hello, how’s it going?”
“Hey, what’s your name?”
“How was your weekend?”

and humorous/sexual comments (e.g. “Your shirt matches my bed spread, basically you belong in my bed”).

The more direct, the better. One interpretation of these findings is that men have a distaste for subtlety. Studies show that men have an overestimation bias — they’re more likely to think a woman is interested in them even when she’s not — so any blatant reinforcement is welcome. A direct pick-up line also suggests a more sexually motivated woman. She wants you, not just a chat.

I find it odd that men weren’t more responsive to direct sexual/humorous come-ons by women; I suspect it depends on the context and delivery. (The sample lines in the study were also real duds.) Or it supports the theory that many men don’t prefer sexually aggressive women. Even if a woman makes the first foray, men like a pursuit.

All this leads me to point to the limitations of studies such as this one. Men were asked to rate pick-up lines, but the effectiveness of the lines was not tested in an actual situation. See, guys are visual creatures; a direct pick-up line won’t work if they don’t find the woman attractive. And assuming the woman is comely enough, I suspect any come-on would work equally well.

Your right ovary rules

If you’re like most women you probably think ovulation is something of a meritocracy — that both ovaries do equal work, and that they alternate every cycle.

If by chance you were not taught that the ovaries soldier on left-right-left-right, then you probably think ovulation is random, like a coin toss.

The second scenario is closer to the truth, but it’s not the whole truth. At least not all the time or for most women.

Fact is, your right ovary is likelier to ovulate more often than the left. This means that in two consecutive months, the right side is probably the one doing more of the hard work of producing the dominant follicle that could become a baby.

At least this is what multiple studies have found, including here (57.7% of women have right-side ovulation), here (54.5 percent have right-side ovulation), and here (62% of total follicles are on the right), and here (larger, more numerous follicles).

Why is the right ovary often dominant?

Anatomical asymmetries between the left and right sides are thought to be the reason. The left ovarian vein drains to the left renal vein and the right ovarian vein to the inferior vena cava. The left renal vein is thought to be under higher pressure than the right and therefore drains slower. Because the left ovary drains slower, the collapsed follicle (called a corpus luteum) takes longer to clear and thereby diminishes the chance that ovulation will occur on that side the following month. No such condition exists on the right side, which is why successive right-side ovulation is more common. Estradiol and testosterone levels are also higher during a right-side cycle; this may also be related to the right ovary’s more efficient plumbing as it flushes lining-plumping hormones into the uterus.

All this leads to some fascinating statistics. For instance, right-sided ovulation favors pregnancy more often than left-sided ovulation (64 percent of pregnancies came from women’s right ovaries), according to a study in Japan that tracked nearly 2,700 natural cycles. Then again, according to another study, odds of pregnancy are best when the dominant follicle develops in the ovary opposite to where ovulation took place in the previous cycle (with pregnancy occurring more often in a right-side cycle that follows a left-side cycle) because the dominant follicles in such cycles are healthier. Even if the right ovary drains faster than the left, the corpus luteum left over from the previous cycle still negatively affects the hormonal health of the dominant follicle. Best to start with a clean slate.

Interestingly, researchers in another study speculate that right-side ovulation is dominant for most of a women’s reproductive years. Toward perimenopause women are more likely to become left-dominant, presumably because the supply of follicles in the right ovary has diminished.

Apart from ultrasound, there’s no reliable way of telling which ovary you’re ovulating from. ( I devote a section of BLONDES to why ovulation is concealed, even to women themselves.) If you think about it, perhaps that’s a good thing.

What body region are you judged by most?

Which do people fixate on most when assessing women’s physical attractiveness — the stomach or the hips?

As I discuss in BLONDES, weight, as estimated by body mass index (BMI), and curves, as measured by waist-to-hip ratio (WHR), are two major factors when assessing women’s bodily attractiveness. Which matters more is a point of contention between various experts.

A new study led by University of York psychologist Piers Cornelissen tries to settle the argument. Implementing a novel way of tracking eye movements, Cornelissen asked male and female volunteers to rate nearly 50 photos of women. The longer their gaze rested on a particular body region, the more that region counted.

There’s a strong argument that curves should matter more than weight when evaluating attractiveness. A low WHR — a relatively thin waist to hip ratio — suggests something about a woman’s hormonal status. Estrogen increases the deposition of body fat on the hips thighs, and bust. Higher estrogen is linked with higher fertility.

But those aren’t the body regions that people fixate on when they look at you, according to Cornellisen’s experiment. The stomach apparently has the most impact. When judging attractiveness, both sexes appear to settle their gaze on the central torso, an area that reveals much about a person’s overall body mass, and not the pelvic and hip areas. This outcome, according to the psychologists, suggests that body mass index is more important in assessing physical attractiveness than curviness.

The study is not conclusive. It’s possible that WHR is assessed more quickly than body mass, which could be why people fixate longer on the torso. Or perhaps the study participants, aware that their eye movements are tracked, are abashed to linger on the pelvic region of the models. The central torso is also quite close to the bust.

Still, it’s another study that falls definitively in the body mass-over-curves camp. And perhaps it helps explain the new rage in stomach-cinchers.