Only for short term relationships women prefer scarred men.
Men with facial scars are more attractive to women seeking short-term relationships, scientists at the University of Liverpool have found.
It was previously assumed that in Western cultures scarring was an unattractive facial feature and in non-Western cultures they were perceived as a sign of maturity and strength. Scientists at Liverpool and Stirling University, however, have found that Western women find scarring on men attractive and may associate it with health and bravery.
What I wonder: Do the scars really increase attraction? Or are more masculine men more likely to get into fights and other dangerous behavior and have facial scars as result?
Researchers investigated how scarring might impact on mate choice for men and women seeking both long-term and short-term relationships. They found that women preferred men with facial scars for short-term relationships and equally preferred scarred and un-scarred faces for long-term relationships. Men, however, regarded women with and without facial scars as equally attractive for both types of relationship.
Dr Rob Burriss, from the University's School of Biological Sciences, explains: "Male and female participants were shown images of faces that displayed scarring from injury or illness, and were asked to rate how attractive they found the person for long-term and short-term relationships.
"Women may have rated scarring as an attractive quality for short-term relationships because they found it be a symbol of masculinity, a feature that is linked to high testosterone levels and an indicator of good genetic qualities that can be passed on to offspring. Men without scars, however, could be seen as more caring and therefore more suitable for long-term relationships.
What I'd like to know: Do more feminine or more masculine women have a greater attraction to men who have facial scars? I'm expecting the most feminine women to feel the most attraction to scarred men.
Roissy's Love In The Time Of Game has me thinking Darwinian thoughts about the attraction between the sexes. Were scarred men in the past seen as proven fighters? How was this female pattern of attraction selected for?
He's going to figure out your cheating heart.
UNFAITHFUL women beware. Chances are your male partner is on your case. In fact, he is likely to suspect infidelities even when you have kept to the straight and narrow. The flip side is that to counter this constant vigilance, women may be better than men at concealing illicit liaisons.
Paul Andrews at Virginia Commonwealth University in Richmond and colleagues gave 203 young heterosexual couples confidential questionnaires asking them whether they had ever strayed, and whether they suspected or knew their partner had strayed. In this, 29 per cent of men said they had cheated, compared with 18.5 per cent of women.
The men were better than women at judging fidelity. "Eighty per cent of women's inferences about fidelity or infidelity were correct, but men were even better, accurate 94 per cent of the time," says Andrews. They were also more likely to catch out a cheating partner, detecting 75 per cent of the reported infidelities compared with 41 per cent discovered by women (Human Nature, vol 19, p 347). However, men were also more likely to suspect infidelity when there was none.
Andrews says this makes evolutionary sense because unlike women, men can never be certain a baby is theirs. "Men have far more at stake," he says. "When a female partner is unfaithful, a man may himself lose the opportunity to reproduce, and find himself investing his resources in raising the offspring of another man."
The next step in this evolutionary arms race? People will genetically test their prospective partners in order to avoid those who have genes that make them more likely to stray. Though men with high status yet with genetic variants that cause a cheating heart will still be able to get women who would rather have a high status cheating mate than a low status faithful mate.
Also, cheaters will look for genetic profiles of prospective mates who either have genetically caused weaknesses in ability to detect cheating or who have genetic profiles that suggest a willingness to look the other way. So maybe the net result will be more happiness and more cheating.
Hi puppets. How are you all doing today? Geppetto says the color red makes men hot for women. When the men see red they charge for the flag.
A groundbreaking study by two University of Rochester psychologists to be published online Oct. 28 by the Journal of Personality and Social Psychology adds color—literally and figuratively—to the age-old question of what attracts men to women.
Through five psychological experiments, Andrew Elliot, professor of psychology, and Daniela Niesta, post-doctoral researcher, demonstrate that the color red makes men feel more amorous toward women. And men are unaware of the role the color plays in their attraction.
The research provides the first empirical support for society's enduring love affair with red. From the red ochre used in ancient rituals to today's red-light districts and red hearts on Valentine's Day, the rosy hue has been tied to carnal passions and romantic love across cultures and millennia. But this study, said Elliot, is the only work to scientifically document the effects of color on behavior in the context of relationships.
Did red hair get selected for because it made women look more hot to men?
Men who think they respond to women in a thoughtful and sophisticated manner are deluding themselves.
Although this aphrodisiacal effect of red may be a product of societal conditioning alone, the authors argue that men's response to red more likely stems from deeper biological roots. Research has shown that nonhuman male primates are particularly attracted to females displaying red. Female baboons and chimpanzees, for example, redden conspicuously when nearing ovulation, sending a clear sexual signal designed to attract males.
"Our research demonstrates a parallel in the way that human and nonhuman male primates respond to red," concluded the authors. "In doing so, our findings confirm what many women have long suspected and claimed – that men act like animals in the sexual realm. As much as men might like to think that they respond to women in a thoughtful, sophisticated manner, it appears that at least to some degree, their preferences and predilections are, in a word, primitive."
We are just smart monkeys.
Women don't get turned on by red in men. Red didn't make women seem any more intelligent or kind.
In the final study, the shirt of the woman in the photograph, instead of the background, was digitally colored red or blue. In this experiment, men were queried not only about their attraction to the woman, but their intentions regarding dating. One question asked: "Imagine that you are going on a date with this person and have $100 in your wallet. How much money would you be willing to spend on your date?"
Under all of the conditions, the women shown framed by or wearing red were rated significantly more attractive and sexually desirable by men than the exact same women shown with other colors. When wearing red, the woman was also more likely to score an invitation to the prom and to be treated to a more expensive outing.
The red effect extends only to males and only to perceptions of attractiveness. Red did not increase attractiveness ratings for females rating other females and red did not change how men rated the women in the photographs in terms of likability, intelligence or kindness.
What color makes men more attractive?
Women have higher pitched voices around ovulation.
A woman's voice tends to rise in pitch the closer she is to ovulation according to research published today in the Royal Society Journal Biology Letters. Researchers believe this is because a higher pitch is more attractive and more feminine, thus signalling fertility to potential partners.
Scientists at the University of California recorded the voices of 69 women to examine whether they raise their voice pitch during ovulation. Using hormone tests the women were recorded at two phases of their ovulatory cycle, once when fertility was low and once near ovulation. Results showed that the closer women were to ovulation, the more they raised their pitch.
Interestingly, this difference was apparent only when women spoke a simple introductory sentence such as 'hi, I'm a student at UCLA' - and not for simple vowel sounds. According to the researchers this shows that women change their voice in relation to fertility and possibly only in social communication contexts.
The findings follow other recent studies which have documented several detectable ovulatory cues in humans, including midcycle increases in body scent attractiveness, flirtation and attention to style of dress.
A 2006 report also finds that women are slaves to their hormones. Just like men.
Thirty-eight normally cycling women provided daily reports of sexual interests and feelings for 35 days. Near ovulation, both pair-bonded and single women reported feeling more physically attractive and having greater interest in attending social gatherings where they might meet men. Pair-bonded women who were near ovulation reported greater extra-pair flirtation and greater mate guarding by their primary partner. As predicted, however, these effects were exhibited primarily by women who perceived their partners to be low on hypothesized good genes indicators (low in sexual attractiveness relative to investment attractiveness). Ovulation-contingent increases in partner mate guarding were also moderated by female physical attractiveness; midcycle increases in mate guarding were experienced primarily by less attractive women, whereas more attractive women experienced relatively high levels of mate guarding throughout their cycle. These findings demonstrate ovulation-contingent shifts in desires and behaviors that are sensitive to varying fitness payoffs, and they provide support for the good genes hypothesis of human female extra-pair mating.
So guys, if you want a girlfriend who gets jealous over you then go for a less attractive woman.
What I want to know: Since the birth control pill prevents ovulation does it reduce the desire of women to dress up? Also, does it lower the average pitch of women's voices?
Once we gain the ability to manipulate the mental switches that cause mating behavior will women choose to put themselves perpetually in the mental state they normally feel just around ovulation? Or will they put themselves in other mental states less oriented toward mating? I'm wondering sexy dressing women will be 50 years from now.
A woman's ability to enjoy sex shows up in her gait.
Paisley, Scotland – September 04, 2008 - A new study found that trained sexologists could infer a woman's history of vaginal orgasm by observing the way she walks. The study is published in the September 2008 issue of The Journal of Sexual Medicine, the official journal of the International Society for Sexual Medicine and the International Society for the Study of Women's Sexual Health.
Led by Stuart Brody of the University of the West of Scotland in collaboration with colleagues in Belgium, the study involved 16 female Belgian university students. Subjects completed a questionnaire on their sexual behavior and were then videotaped from a distance while walking in a public place. The videotapes were rated by two professors of sexology and two research assistants trained in the functional-sexological approach to sexology, who were not aware of the women's orgasmic history.
The results showed that the appropriately trained sexologists were able to correctly infer vaginal orgasm through watching the way the women walked over 80 percent of the time. Further analysis revealed that the sum of stride length and vertebral rotation was greater for the vaginally orgasmic women. "This could reflect the free, unblocked energetic flow from the legs through the pelvis to the spine," the authors note.
There are several plausible explanations for the results shown by this study. One possibility is that a woman's anatomical features may predispose her to greater or lesser tendency to experience vaginal orgasm. According to Brody, "Blocked pelvic muscles, which might be associated with psychosexual impairments, could both impair vaginal orgasmic response and gait." In addition, vaginally orgasmic women may feel more confident about their sexuality, which might be reflected in their gait. "Such confidence might also be related to the relationship(s) that a woman has had, given the finding that specifically penile-vaginal orgasm is associated with indices of better relationship quality," the authors state. Research has linked vaginal orgasm to better mental health.
The study provides some support for assumptions of a link between muscle blocks and sexual function, according to the authors. They conclude that it may lend credibility to the idea of incorporating training in movement, breathing and muscle patterns into the treatment of sexual dysfunction.
Will training a woman in how to walk increase her sexual pleasure? Or does the different walk flow from differences in muscle and bone structure or perhaps differences in their nervous system that sexual responses? I'm going to guess that there's a big genetic component to how men and women walk.
Update: Razib uses this story to show a picture of Israeli model Bar Rafaeli. (but I'm totally turned off because she smokes - what a waste). His commenters bring up the question of the direction of flow of causality. Does having a vaginal orgasm cause a woman to walk differently? Or does the same underlying neuro-muscular system cause both the different walk and the greater ease of having vaginal orgasms? I'm guessing the latter and I'm guessing an underlying genetic cause. Ease of orgasm is probably genetically inherited.
Men who have immune system genes dissimilar to women have odors which are more attractive to women. This is probably an evolutionary consequence of the advantage of giving one's children genetically diverse immune systems. But the hormones in the contraceptive pill alter sense of smell of women so they are more attracted to men who are immunologically more similar.
The contraceptive pill may disrupt women's natural ability to choose a partner genetically dissimilar to themselves, research at the University of Liverpool has found.
The Pill leads a woman's attraction machinery astray.
Disturbing a woman's instinctive attraction to genetically different men could result in difficulties when trying to conceive, an increased risk of miscarriage and long intervals between pregnancies. Passing on a lack of diverse genes to a child could also weaken their immune system.
So the Pill causes a mismatch in mate selection.
Humans choose partners through their body odour and tend to be attracted to those with a dissimilar genetic make-up to themselves, maintaining genetic diversity. Genes in the Major Histocompatibility Complex (MHC), which helps build the proteins involved in the body's immune response, also play a prominent role in odour through interaction with skin bacteria. In this way these genes also help determine which individuals find us attractive.
The research team analysed how the contraceptive pill affects odour preferences. One hundred women were asked to indicate their preferences on six male body odour samples, drawn from 97 volunteer samples, before and after initiating contraceptive pill use.
Craig Roberts, a Lecturer in Evolutionary Psychology who carried out the work in collaboration with the University of Newcastle, said: "The results showed that the preferences of women who began using the contraceptive pill shifted towards men with genetically similar odours.
There's an even bigger problem: If a woman on the Pill meets a guy, finds him pheromonally attractive, gets married, and then stops using the Pill she can suddenly find her husband's smell very much not to her liking.
"Not only could MHC-similarity in couples lead to fertility problems but it could ultimately lead to the breakdown of relationships when women stop using the contraceptive pill, as odour perception plays a significant role in maintaining attraction to partners."
How many marriages and relationships has the Pill brought together which fell apart when the woman stopped taking the Pill?
What could be done about it: One genetic testing becomes cheap and widely available online dating services could match men and women by comparing Major Histocompatibility Complex (MHC) genes. Avoid dating someone who might seem attractive because you are on the Pill.
But doesn't the MHC attraction mechanism work for men as well? They won't be on the Pill. Are men finding that funny-smelling women who are on the Pill are hitting on them? Someone should do a study on this.
The discovery reported in this post is yet another example of how we are genetically programmed to do and feel as we do.
Some social science research provides evidence for expected truths. Other times it comes up with unintuitive results. Here's a piece of research that does both at the same time. If a good-looking guy has just flirted with your girlfriend she is more likely to forgive you for a bad thing you did?
Temptation may be everywhere, but it's how the different sexes react to flirtation that determines the effect it will have on their relationships. In a new study, psychologists determined men tend to look at their partners in a more negative light after meeting a single, attractive woman. On the other hand, women are likelier to work to strengthen their current relationships after meeting an available, attractive man.
I can understand the evolutionary origin of the male reaction. When he thinks he's got other options he's more likely to be less tolerant of perceived short-comings of his mate. But the female reaction is more puzzling. Anyone got a good evolutionary explanation for the origin of this behavior?
Men may not see their flirtations with an attractive woman as threatening to the relationship while women do, according to findings from a study in the July issue of the Journal of Personality and Social Psychology, published by the American Psychological Association. Researchers found that women protect their relationship more when an attractive man enters the picture but men look more negatively at their partner after they've met an available, attractive woman. Men can learn to resist temptation when trained to think that flirting with an attractive woman could destroy their relationship, said lead author John E. Lydon, PhD, of McGill University in Montreal.
Researchers conducted seven laboratory experiments using 724 heterosexual men and women to see how college-aged men and women in serious relationships react when another attractive person enters the mix.
Maybe the woman is more afraid of getting dumped by her guy if she flirts and therefore she tries harder to strengthen the relationship to compensate for the potential damage done?
In one study, 71 unsuspecting male participants were individually introduced to an attractive woman. Roughly half the men met a "single" woman who flirted with them. The other half met an "unavailable" woman, who simply ignored them.
Immediately after this interaction, the men filled out a questionnaire in which they were asked how they would react if their "romantic partner" had done something that irritated them, such as lying about the reason for canceling a date or revealing an embarrassing tidbit about them. Men who met the attractive "available" woman were 12 percent less likely to forgive their significant others. In contrast, 58 women were put in a similar situation. These women, who met an "available" good-looking man, were 17.5 percent more likely to forgive their partners' bad behavior.
Do these results make sense to you?
Why do psychopaths exist? The ladies help the psychopaths reproduce by going to bed with them. Men who are narcissistic, self-obsessed, liars, psychopaths, Machiavellian, and thrill-seekers get laid more.
Bad boys, it seems, really do get all the girls. Women might claim they want caring, thoughtful types but scientists have discovered what they really want – self-obsessed, lying psychopaths.
A study has found that men with the "dark triad" of traits – narcissism, thrill- seeking and deceitfulness – are likely to have a larger number of sexual affairs.
To be fair, not all ladies want these guys. But the genes that cause these personality characteristics wouldn't exist if men and women didn't get together to pass the genes along.
Are all these traits caused by the same genetic variations? Or are there different traits causing different subsets of these traits and each subset of traits has been separately selected for? The study was done on college students.
But being just slightly evil could have an upside: a prolific sex life, says Peter Jonason at New Mexico State University in Las Cruces. "We have some evidence that the three traits are really the same thing and may represent a successful evolutionary strategy."
Jonason and his colleagues subjected 200 college students to personality tests designed to rank them for each of the dark triad traits. They also asked about their attitudes to sexual relationships and about their sex lives, including how many partners they'd had and whether they were seeking brief affairs.
The study found that those who scored higher on the dark triad personality traits tended to have more partners and more desire for short-term relationships, Jonason reported at the Human Behavior and Evolution Society meeting in Kyoto, Japan, earlier this month. But the correlation only held in males.
Once the genetic causes of these behaviors are known will women choose to have offspring with these traits? Will the frequency of these traits rise or fall once it becomes possible to intentionally pass on or avoid passing on these traits?
Some women might reason that they want their kids to be Machiavellian, extremely charming, obsessed with looking out for number 1, and extroverted in order to better succeed.
To men who do not have and not like these traits: Fake them for the sake of the human race. If you can attract women by pretending to have these traits and then make babies you will displace the genes of psychopaths and narcissists from the human race. Roissy thinks a "beta" male can learn to act like an "alpha" and project traits that attract women. Use Roissy's techniques to outcompete those who have the James Bond personality.
For most couples mutual attraction gradually wanes. But for some statistical outliers the initial intense attraction seems to last.
Psychologists studying relationships confirm the steady decline of romantic love. Each year, according to surveys, the average couple loses a little spark. One sociological study of marital satisfaction at the University of Nebraska-Lincoln and Penn State University kept track of more than 2,000 married people over 17 years. Average marital happiness fell sharply in the first 10 years, then entered a slow decline.
Think about all those people becoming steadily less satisfied with each other. The outcomes of natural selection are cruel.
Are those who feel thrilled about their mates for many years different in some neurobiological way? One would expect that to be the case. Some scientists decided to investigate the statistical outliers using brain scans.
About 15 years ago, Arthur Aron, a social psychologist at Stony Brook University, became curious about couples outside the norm. His own work turned up the usual pattern of declining passion. But he was drawn to what statisticians call outliers, points way off the curve. These dots represented people who claimed they'd been madly in love for years. "I didn't know what to make of that," Dr. Aron says. "Was it random error? Were they self-deceiving? Were they deceiving others? Because it's not supposed to happen."
Not supposed to happen? I wouldn't say that. More likely there's a large range of genetic variations that govern how the brain develops in areas related to sex and bonding. Some people probably get genetic variations that make them feel romantically high for decades just like some people are natural optimists who always feel happy even in adverse circumstances.
Brain scans show the perpetually in love as different than the masses. Those people in long term relationships who profess to still feel very excited about their partners have more intense brain activity in the ventral tegmental area of the brain just like the newly fallen in love do.
Days after Mrs. Tucker's brain scan, Dr. Brown, the neuroscientist, sat in her book-lined office looking at the results. "Wow, just wow," she recalls thinking. Mrs. Tucker's brain reacted to her husband's photo with a frenzy of activity in the ventral tegmental area. "I was shocked," Dr. Brown says.
The brain scan confirmed what Mrs. Tucker said all along. But when she learned the result, she too was a bit surprised. "It's not something I expected after 11 years," she says. "But having it, it's like a gift."
The scan also showed a strong reaction in Mrs. Tucker's ventral pallidum, an area suspected from vole studies to have links with long-term bonds. Mrs. Tucker apparently enjoyed old love and new. In the months since, Dr. Brown analyzed data from four more people, including Ms. Jordan, who also showed brain activity associated with new love. The study is ongoing, and more volunteers are being sought.
This research has many ramifications. Do those who stay thrilled have lower rates of divorce? I would expect so. But people who have the neurological tendency to maintain intense romantic love probably are at risk for getting into relationships with people who do not share that tendency. So they can get their hearts broken pretty badly. If they could find each other (neuro-scan dating services that screen to pair people up with neuro-like potential mates) then they could bond to someone who will bond back just as strongly and for just as longly.
Longer term: Neurobiologists will develop a better understanding of why some maintain a long term romantic high off of pair bonding. They will eventually develop the ability to manipulate it. Will people decide to undergo treatments to prevent their romantic feelings from declining with time? Or will they turn down and suppress these feelings so that romance becomes less of a distraction from career ambitions?
What happens once bonding behavior gets traced back to genetic variations and genetic engineering of offspring becomes possible? Will people choose to give their children genetic variations that make them pair up in very stable long-lasting relationships? Or will they give future generations genetic variations that cause serial monogamy or general promiscuity? Also, will parents make male offspring and female offspring more or less different in their mating preferences?
The coming of offspring genetic engineering probably won't unite humanity into a single style of living. I expect society to divide up into groups that make different sorts of decisions about genetic endowments for how their children will form relationships, romantic and otherwise. Some groups will choose genetic variations that make their kids more monogamous. Others will intentionally create children who are more promiscuous. Still others will genetically engineer women to happily join polygamous marriages without jealousy.
Also see my previous post Romantic Love Seen As Motivation Or Drive Rather Than Emotional State.
Update: If you aren't going to get divorced there is some appeal to the idea of making yourself feel thrilled once again about your spouse. Tuning up your brain's love spot would probably increase your enjoyment of life. But if your spouse is abusing you or otherwise creating a disaster in your life then you really need a way to turn down your enthusiasm far enough to get out of the relationship.
The ladies just don't get as much of a thrill out of capturing territory in a video game. File under "no surprise here".
STANFORD, Calif. - Allan Reiss, MD, and his colleagues have a pretty good idea why your husband or boyfriend can't put down the Halo 3. In a first-of-its-kind imaging study, the Stanford University School of Medicine researchers have shown that the part of the brain that generates rewarding feelings is more activated in men than women during video-game play.
"These gender differences may help explain why males are more attracted to, and more likely to become 'hooked' on video games than females," the researchers wrote in their paper, which was recently published online in the Journal of Psychiatric Research.
More than 230 million video and computer games were sold in 2005, and polls show that 40 percent of Americans play games on a computer or a console. According to a 2007 Harris Interactive survey, young males are two to three times more likely than females to feel addicted to video games, such as the Halo series so popular in recent years.
The ladies can capture the territory. Doing that just doesn't turn up the mesocorticolimbic center of their brains as much as it does for guys.
"The females 'got' the game, and they moved the wall in the direction you would expect," said Reiss, who is director of the Center for Interdisciplinary Brain Sciences Research. "They appeared motivated to succeed at the game. The males were just a lot more motivated to succeed."
After analyzing the imaging data for the entire group, the researchers found that the participants showed activation in the brain's mesocorticolimbic center, the region typically associated with reward and addiction. Male brains, however, showed much greater activation, and the amount of activation was correlated with how much territory they gained. (This wasn't the case with women.) Three structures within the reward circuit - the nucleus accumbens, amygdala and orbitofrontal cortex - were also shown to influence each other much more in men than in women. And the better connected this circuit was, the better males performed in the game.
The findings indicate, the researchers said, that successfully acquiring territory in a computer game format is more rewarding for men than for women. And Reiss, for one, isn't surprised. "I think it's fair to say that males tend to be more intrinsically territorial," he said. "It doesn't take a genius to figure out who historically are the conquerors and tyrants of our species-they're the males."
So then when offspring genetic engineering becomes possible will prospective parents choose to give their sons or daughters brains that get more or less thrill out of territory capture than the average boy or girl born today? Will genetically engineered boys be more or less territorial than they are today? What about for the girls? Parents might choose to give girls some of the cognitive characteristics that make them more likely to strive to succeed and rise above in competitions at work. Think that likely?
Does humor flow from the desire of males to demonstrate their virility?
Humour appears to develop from aggression caused by male hormones, according to a study published in this week’s Christmas issue of the BMJ.
Professor Sam Shuster conducted a year long study observing how people reacted to him as he unicycled through the streets of Newcastle upon Tyne. What began as a hobby turned into an observational study after he realized that the huge number of stereotypical and predictable responses he received must be indicative of an underlying biological phenomenon.
The study was an observation of people’s reactions to a sudden unexpected exposure to a new phenomenon - in this case unicycling, which at the time few had seen. He documented the responses of over 400 individuals, and observed the responses of many others.
Over 90% of people responded physically, for example with an exaggerated stare or a wave. Almost half responded verbally – more men than women. Here, says Professor Shuster, the sex difference was striking. 95% of adult women were praising, encouraging or showed concern. There were very few comic or snide remarks. In contrast, only 25% of adult men responded as did the women, for example, by praise or encouragement; instead 75% attempted comedy, often snide or combative as an intended put-down.
Equally striking, he says, was the repetitive and predictable nature of the comments from men; two thirds of their ‘comic’ responses referred to the number of wheels - “Lost your wheel?”, for example.
Professor Shuster also noticed the male response differed markedly with age, moving from curiosity in childhood (years 5-12) – the same reaction as young girls, - to physical and verbal aggression in boys aged 11-13 who often tried to get him to fall off the unicycle.
Responses became more verbal during the later teens, turning into disparaging ‘jokes’ or mocking songs. This then evolved into adult male humour – characterized by repetitive, humorous verbal put-downs concealing a latent aggression. Young men in cars were particularly aggressive. Professor Shuster notes that this is the age when men are at the peak of their virility. The ‘jokes’ were lost with age as older men responded more neutrally and amicably with few attempts at a jovial put-down.
The female response by contrast, was subdued during puberty and late teens – normally either apparent indifference or minimal approval. It then evolved into the laudatory and concerned adult female response.
What I'd like to see: A study of female comics where their blood testosterone levels are compared to the average testosterone levels of women of similar age, socio-economic background, and so on. My guess is that female comics have more testosterone than the average woman.
What is the evolutionary purpose or intent of male humor? To demonstrate reproductive fitness to women by showing wit and cleverness? Or to make other men feel inferior and less likely to compete for women? Or some other purpose?
Hamilton, ON. Sept. 24, 2007 – Men who have lower-pitched voices have more children than do men with high-pitched voices, researchers have found. And their study suggests that for reproductive-minded women, mate selection favours men with low-pitched voices.
The study, published in Biology Letters, offers insight into the evolution of the human voice as well as how we choose our mates.
In previous studies, David Feinberg, assistant professor in the Department of Psychology, Neuroscience and Behaviour at McMaster University, and his colleagues have shown that women find deeper male voices to be more attractive, judging them to be more dominant, older, healthier and more masculine sounding. Men, on the other hand, find higher-pitch voices in women more attractive, subordinate, feminine, healthier and younger sounding.
“While we find in this new study that voice pitch is not related to offspring mortality rates,” says Feinberg,” we find that men with low voice pitch have higher reproductive success and more children born to them.”
What I really want to know: If deep voiced men and high pitched voiced women make babies then are the male babies not as deeped voiced as their dads and are the female babies not as high pitched voiced as their moms? To put it another way: Do more masculine mothers give birth to more masculine sons and do more feminine fathers sire more feminine daughters?
Some day prospective parents will genetically engineer their male offspring to have deeper voices and female offspring to have higher pitched voices. How many parents will give their daughters deeper voices to perhaps help them do better in work careers?
Also, once plastic surgery for voice tone modification becomes safe and effective how many people will change their voice pitch and in which direction?
Of course, if you want to increase your satisfaction with romantic relationships some day there'll be another option besides body alterations that enhance your appeal to others: modify your brain so that you find more kinds of human body shapes appealing. Then you could find easy pickings and satisfaction with those who are less attractive to the majority. Though that approach will become less valuable once most people get their appearances enhanced. You won't be able to find as many lonely people who others find unattractive. Jack Black's distorted view of a fat Gwyneth Paltrow will some day become achievable in real life. But before that happens obesity will become easily curable.
If you think someone smells sweet it might be down to genes.
To many, urine smells like urine and vanilla smells like vanilla. But androstenone, a derivative of testosterone that is a potent ingredient in male body odor, can smell like either - depending on your genes. While many people perceive a foul odor from androstenone, usually that of stale urine or strong sweat, others find the scent sweet and pleasant. Still others cannot smell it at all.
New research from Rockefeller University, performed in collaboration with scientists at Duke University in North Carolina, reveals for the first time that this extreme variability in people's perception of androstenone is due in large part to genetic variations in a single odorant receptor called OR7D4. The research is reported September 16 as an advance online publication of the journal Nature.
Combine bind genetic tests for OR7D4 with genetic tests for genes that regulate Androstenone secretion and you have the beginnings of a genetic compatibility test. Online match-making services will some day include genetic profile matching. Why go to the trouble of meeting someone you get matched with online if one of you is going to think the other one has a really disgusting smell?
So now we need scientists to discover genetic variations that regulate androstenone production and secretion.
Androstenone, found in higher concentrations in the urine and sweat of men than of women, is used by some mammals to convey social and sexual information, and the ability to perceive androstenone's scent may have far-reaching behavioral implications for humans.
In the largest study ever conducted of its kind, researchers at Rockefeller University presented nearly 400 participants with 66 odors at two different concentrations and asked them to rate the pleasantness and intensity of each odor. When scientists at Duke University identified OR7D4 as a receptor that androstenone selectively activates, Leslie Vosshall, Chemers Family Associate Professor and head of the Laboratory of Neurogenetics and Behavior at Rockefeller University and Andreas Keller, a postdoc in her lab, formed a collaboration with them, and began collecting blood samples from participants and isolated their DNA. The Duke team, led by Hiroaki Matsunami, used DNA from each participant to sequence the gene that encodes the OR7D4 receptor.
You can bet that many more genetic variations that influence physical attraction will be found.
More fun with human sexuality and attraction.
Whether we are seeking a mate or sizing up a potential rival, good-looking people capture our attention nearly instantaneously and render us temporarily helpless to turn our eyes away from them, according to a new Florida State University study.
“It’s like magnetism at the level of visual attention,” said Jon Maner, an assistant professor of psychology at FSU, who studied the role mating-related motives can play in a psychological phenomenon called attentional adhesion. His findings are published in the September issue of the Journal of Personality and Social Psychology.
The paper, “Can’t Take My Eyes Off You: Attentional Adhesion to Mates and Rivals,” is one of the first to show how strongly, quickly and automatically we are attuned to attractive people, he said. FSU graduate students Matthew Gailliot, D. Aaron Rouby and Saul Miller co-authored the study.
In a series of three experiments, Maner and his colleagues found that the study participants, all heterosexual men and women, fixated on highly attractive people within the first half of a second of seeing them. Single folks ogled the opposite sex, of course, but those in committed relationships also checked people out, with one major difference: They were more interested in beautiful people of the same sex.
Why the attention paid to same sex attractive people? Jealousy.
In the experiments, study participants -- 120 people in the first study and 160 and 162 in the second and third studies, respectively -- completed questionnaires to determine the extent to which they were motivated to seek out members of the opposite sex. They then took part in a series of “priming” activities before they were shown photos of highly attractive men, highly attractive women, average-looking men and average-looking women.
After a photo of one of the faces flashed in one quadrant of a computer screen, the participants were required to shift their attention away from that face to somewhere else on the screen. Using a precise measure of reaction time, Maner found that it took the participants longer to shift their attention away from the photos of the highly attractive people.
Maner said he was surprised that his studies showed little differences between the sexes when it came to fixating on eye-catching people.
“Women paid just as much attention to men as men did to women,” he said. “I was also surprised that jealous men paid so much attention to attractive men. Men tend to worry more about other men being more dominant, funny or charismatic than they are. But when it comes to concerns about infidelity, men are very attentive to highly attractive guys because presumably their wives or girlfriends may be too.”
So then can one measure loss of attraction to one's own mate by measuring how much people pay attention to same sex attractive people? Do people who are ready to file for divorce pay less attention to same sex attractive people?
Also, when people become involved in a relationship do they become more averse to spending time with their more attractive friends?
I'd also like to see this phenomenon measured as a function of blood sexual hormone levels. Do people with more testosterone pay more attention to same and opposite sex attractive pictures?
Really, I'm not joking. Max Krasnow and a team at Yale and UC Santa Barbara have found that women can navigate as well as men but their skills only show up when shopping.
The team asked the men and women to show the direction of a stall where they had bought a certain food, such as strawberries or tomatoes, using a compass.
A zero degree error meant the subjects were bang on target, while 90 degrees meant they were hopeless.
“Men were making 33 degree pointing error, when women were around 25 degree, which is a 27 per cent improvement,” said Mr Krasnow.Women also did better with a high-calorie food, such as a doughnut, compared with a stick of celery.
Women had much better accuracy for where to reach higher calorie foods as compared to vegetables and other lower calorie foods. Is it any wonder that we don't eat enough vegetables? Women have a hard time finding the produce section. Suddenly they find themselves in the pastry aisle.
Calorie malnutrition has been the biggest killer in human history. Women were the gatherers. They know how to get back to the places with the best food gathering potential. Whereas men had to know how to track prey over a larger range of areas.
How to make use of this knowledge? Depends on your motives. How about putting a women's clothing store next to Dunkin Donuts or International House of Pancakes?
So how to enhance the cognitive performance of both boys and girls? Put them in school together.
Yes, women prefer pinker colors yet we all like blue.
A study in the August 21st issue of Current Biology, a publication of Cell Press, reports some of the first conclusive evidence in support of the long-held notion that men and women differ when it comes to their favorite colors. Indeed, the researchers found that women really do prefer pink—or at least a redder shade of blue—than men do.
"Although we expected to find sex differences, we were surprised at how robust they were, given the simplicity of our test," said Anya Hurlbert of Newcastle University, UK. In the test, young adult men and women were asked to select, as rapidly as possible, their preferred color from each of a series of paired, colored rectangles.
Blue Man Group embody our basic human preference for blue.
The universal favorite color for all people appears to be blue, they found. "On top of that, females have a preference for the red end of the red-green axis, and this shifts their color preference slightly away from blue towards red, which tends to make pinks and lilacs the most preferred colors in comparison with others," she said.
So then when genetically engineered skin color becomes possible will anyone opt for blue skin or blue hair? Look at how popular blue eyes are.
Does it make more sense for women to die their hair blue to attract men and for men to go for a more reddish color to attract women? Or does the color preference not extend to preferences for mates? After all, blond hair is most desired in women. Yet blue eyes are too.
What I want to know: Does color preference vary at all according to sexual orientation? For example, do homosexual men lean more toward lilacs than hetero guys? Or do homosexual females lean more toward blue preference than hetero females? Also, does blood testosterone level influence color preference?
Overall, the differences between men and women were clear enough that the seasoned researchers can now usually predict the sex of a participant based on their favorite-color profile.
The color preference seems to track across at least 2 races.
To begin to address whether sex differences in color preference depend more on biology or culture, the researchers tested a small group of Chinese people amongst the other 171 British Caucasian study participants. The results among the Chinese were similar, Hurlbert said, strengthening the idea that the sex differences might be biological.
The question arises: Where does this color preference come from?
The explanation might go back to humans' hunter-gatherer days, when women—the primary gatherers--would have benefited from an ability to key in on ripe, red fruits.
"Evolution may have driven females to prefer reddish colors--reddish fruits, healthy, reddish faces," Hurlbert said. "Culture may exploit and compound this natural female preference."
Reddish faces as indicators of good nutrition and lots of red blood cells seems plausible. But reddish fruits? Seems like many more plant foods are green. Why would food gathering favor reddish foods? Are reddish plants more likely to be digestible for calories than, for example, green leaves?
Hurlbert suspects the preference for blue might be due to the desirability of blue skies for hunting or perhaps blue water for greater purity and safety. Can you think of another reason for the blue preference?
Frederick and Haselton lead a team that photographed 99 male undergraduates. A panel of independent judges rated the young men on a nine-point scale, with "1" being much less muscular than average and "9" being much more muscular than average. The researchers then asked the men about their sexual histories.
When compared with their less-muscular peers, young men who were more muscular than average were twice as likely to have had more than three sex partners in their lives.
In another study, Frederick and Haselton asked 120 undergraduate males to rate their own physiques on the same scale and then asked them about their sexual histories.
The self-identified muscular men had not only had more sexual partners than their less burly peers, but they were twice as likely to have had brief flings or one-night stands with women. The difference in the number of sexual partners reported by the men who were more muscular than average was also notable: They reported having had an average of four partners, compared with an average of 1.5 partners for men who reported average or below-average muscularity.
In a similar study, Frederick and Haselton asked 60 undergraduate males an additional question: How many affairs had they had with women who already had a boyfriend at the time of the affair? Muscularity mattered here as well. The more muscular individuals were twice as likely as their less well-built peers to have hooked up with someone else's sweetheart.
Women know the muscular men have different personalities and behaviors as compared to the skinnier guys.
Interestingly, women in the study seemed to be on to muscular men. When presented with six standardized silhouettes of men ranging from brawny to slender, 141 undergraduate women consistently identified the most muscular ones as not only less likely to commit but also more volatile and domineering. In the study, the women rated "toned" guys - the physical type two notches down from "brawny" - as the most sexually attractive.
"Moderate muscularity demonstrates that men are in good condition, but they're not so overloaded with testosterone that they are volatile, aggressive and dominant," Frederick said. "Just based on their experiences, women seem to be able to weigh good and bad male traits."
Still, in a study by Frederick and Haselton of 82 college coeds, most women reported that their short-term partners were more muscular than their long-term ones. They characterized their long-term - and presumably less muscular - partners as more trustworthy and romantic than their one-night stands or brief affairs.
I vaguely recall earlier studies that purported to show that upper class women prefer men with less muscles than lower class women.
Will men adjust their body shapes when they change their minds about how long term they want their relationships to be? Time to get married and therefore time to slim down the muscles somewhat in order to appear more caring?
We can expect by using biotechnology future males will have more muscles, less body fat, less gray hair, and less receding hairlines.
When women win they get a bigger mental reward before ovulation than after.
Fluctuations in sex hormone levels during women's menstrual cycles affect the responsiveness of their brains' reward circuitry, an imaging study at the National Institute of Mental Health (NIMH), a component of the National Institutes of Health (NIH), has revealed. While women were winning rewards, their circuitry was more active if they were in a menstrual phase preceding ovulation and dominated by estrogen, compared to a phase when estrogen and progesterone are present.
My guess is that it is more rewarding to be around women who are in their pre-ovulatory phase.
What is the purpose of this effect of neurons on reward centers? Is it to make women get greater enjoyment from sex when they are more likely to get pregnant?
Reward system circuitry includes: the prefrontal cortex, seat of thinking and planning; the amygdala, a fear center; the hippocampus, a learning and memory hub; and the striatum, which relays signals from these areas to the cortex. Reward circuit neurons harbor receptors for estrogen and progesterone. However, how these hormones influence reward circuit activity in humans has remained unclear.
To pinpoint hormone effects on the reward circuit, Berman and colleagues scanned the brain activity of 13 women and 13 men while they performed a task involving simulated slot machines. The women were scanned before and after ovulation.
The fMRI pictures showed that when the women were anticipating a reward, they activated the amygdala and a cortex area behind the eyes that regulates emotion and reward-related planning behavior more during the pre-ovulation phase (four to eight days after their period began) than in the post-ovulatory phase.
When they hit the jackpot and actually won a reward, women in the pre-ovulatory phase activated the striatum and circuit areas linked to pleasure and reward more than when in the post-ovulatory phase.
Both reward anticipation and reward reception were enhanced by estrogen.
The researchers also confirmed that the reward-related brain activity was directly linked to levels of sex hormones. Activity in the amygdala and hippocampus was in lockstep with estrogen levels regardless of cycle phase; activity in these areas was also triggered by progesterone levels while women were anticipating rewards during the post-ovulatory phase. Activity patterns that emerged when rewards were delivered during the post-ovulatory phase suggested that estrogen's effect on the reward circuit might be altered by the presence of progesterone during that period.
So then do women enjoy life less after they've ovulated? Also, do women on birh control pills get more or less pleasure from rewards? Same question for post-menopausal women who have less estrogen in their bodies? Do they get less of a thrill from rewards?
What is going to happen with this information in the long run? Imagine drugs that cause or block the effects of estrogen on reward centers and pleasure-related neurons. Will women choose to have their minds always in the pre-ovulatory state and feel more reward from wins and gains? Or will they choose to block the effects of higher estrogen on their brains?
Natural selection gave blue eyed men a preference for blue eyed women. Natural selection for women whose babies will be more obviously testable for paternity gave many men a preference for blue-eyed women.
Before you request a paternity test, spend a few minutes looking at your child’s eye color. It may just give you the answer you’re looking for. According to Bruno Laeng and colleagues, from the University of Tromso, Norway, the human eye color reflects a simple, predictable and reliable genetic pattern of inheritance. Their studies1, published in the Springer journal Behavioral Ecology and Sociobiology, show that blue-eyed men find blue-eyed women more attractive than brown-eyed women. According to the researchers, it is because there could be an unconscious male adaptation for the detection of paternity, based on eye color.
Since blue eyes are a recessive trait the reason for the preference for blue eyes by men is explainable with classical Mendelian genetics:
The laws of genetics state that eye color is inherited as follows:
1. If both parents have blue eyes, the children will have blue eyes.
2. If both parents have brown eyes, a quarter of the children will have blue eyes, and three quarters will have brown eyes.
3. The brown eye form of the eye color gene (or allele) is dominant, whereas the blue eye allele is recessive.
It then follows that if a child born to two blue-eyed parents does not have blue eyes, then the blue-eyed father is not the biological father. It is therefore reasonable to expect that a man would be more attracted towards a woman displaying a trait that increases his paternal confidence, and the likelihood that he could uncover his partner’s sexual infidelity.Eighty-eight male and female students were asked to rate facial attractiveness of models on a computer. The pictures were close-ups of young adult faces, unfamiliar to the participants. The eye color of each model was manipulated, so that for each model’s face two versions were shown, one with the natural eye color (blue/brown) and another with the other color (brown/blue). The participants’ own eye color was noted.
Both blue-eyed and brown-eyed women showed no difference in their preferences for male models of either eye color. Similarly, brown-eyed men showed no preference for either blue-eyed or brown-eyed female models. However, blue-eyed men rated blue-eyed female models as more attractive than brown-eyed models.
That means there is a place or set of places in the genome where genetic variations give some of us our pronounced preference for blue eyes. I also prefer green eyes. Does the same set of genetic variations cause both preferences?
There's a lesson here for for future parents who will be able to use genetic engineering techniques to choose eye color for their daughters: Choose blue to maximize the appeal of their daughters. The blue color won't cost them any with the brown eyed guys but will boost their appeal to blue eyed guys.
However the very trait that increases attractiveness of women has a different effect in men: It decreases the range of women who they find attractive. If you want your son to find a larger range of women attractive then it actually makes sense to give him brown eyes.
Blue eyed men tend to have blue eyed romantic partners.
In a second study, a group of 443 young adults of both sexes and different eye colors were asked to report the eye color of their romantic partners. Blue-eyed men were the group with the largest proportion of partners of the same eye color.
According to Bruno Laeng and colleagues, “It is remarkable that blue-eyed men showed such a clear preference for women with the same eye color, given that the present experiment did not request participants to choose prospective sexual mates, but only to provide their aesthetic or attractiveness responses…based on face close-up photographs.” Blue-eyed men may have unconsciously learned to value a physical trait that can facilitate recognition of own kin.
Once offspring genetic engineering becomes possible I am expecting we will see a huge surge in births of blue eyed and blond hair daughters. They'll also have larger lips, more bottle-shaped bodies, greater symmetry, higher cheekbones, and every other feature that is considered sexy and beautiful. People will make their sons more physically attractive as well. The future will be beautiful.
Natural selection did not create human male and female sexual desires that are mutually compatible. Men in long term relationships sound sexually frustrated.
The researchers from Hamburg-Eppendorf University interviewed 530 men and women about their relationships.
They found 60% of 30-year-old women wanted sex "often" at the beginning of a relationship, but within four years of the relationship this figure fell to under 50%, and after 20 years it dropped to about 20%.
In contrast, they found the proportion of men wanting regular sex remained at between 60-80%, regardless of how long they had been in a relationship.
Women maintain their interest better in men who have higher status than their mates
The Germans found, however, that living apart slows the decline in female libido, confirming the maxim “absence makes the heart grow fonder”.
Women whose husbands or boyfriends have higher educational qualifications than their own also maintain their sex drive. This, speculates Klusmann, is because such men are regarded as a “valuable mate of choice” by other women.
Some people think nature is great. Nature is all about conflict and competition. Natural selection has produced males and females who have instincts which give desires and drives that make them come up well less than perfectly compatible. If men and women ever become more compatible it will be due to genetic engineering and other biotechnologies that adjust us to make us have more mutually satisfying desires.
When sexual desires and drive become far more manipulable with neurobiotechnology will men and women in long term relationships more often increase the woman's sex drive or decrease the man's? I suspect the decision will be made at least on time availability. People will turn down their sex drives when working long hours and raising kids but turn up their sexual desire when they have more time. Taking a vacation? Turn up your libido.
To the extent that genetic variations will turn out to predict sex drives in long term relationships I'm expecting some people to genetically evaluate potential spouses based on the expected difference in their sex drives. I also expect them to genetically evaluate for how likely their mate is to cheat on them. I fully expect human geneticists to find genetic variations that increase promiscuity.
This result opens up all sorts of possibilities. Dr Viren Swami of University College London and Dr Martin Tovée of Newcastle University found that before they eat dinner men find heavier set and less curvy women more attractive.
How full a man's stomach is can dictate the type of woman he will fancy, UK research suggests.
A study of 61 male university students found those who were hungry were attracted to heavier women than those who were satiated.
The hungry men also paid much less attention to a woman's body shape and regarded less curvy figures as more attractive.
The molecular mechanism by which this works might be manipulable some day. Could a drug target brain locations which govern attraction without affecting whether a person feels hungry? If so, a guy could (knowingly or not) take a drug that makes his skinny or fatty mate look more attractive all the time.
I've long thought that a drug which increased the range of men or women which a person finds attractive would allow a person to be a lot more satisfied when pursuing the opposite sex. Also, a drug or other treatment that allowed a mind to find a single person the most attractive (say stare at that person while getting the treatment to imprint that shape as ideal) would allow everyone to think their mate is most attractive.
Biotechnological manipulation of feelings of attraction might not cause natural selection problems. In the future people will genetically engineer their offspring anyway. So hooking up with a person who is less attractive due to genetic problems doesn't have to lead to genetically less fit offspring. That will be able to get fixed with genetic engineering at the time of conception.
Male students entering and exiting a school dining hall were shown pictures and women and asked to rate them.
They recruited male university students as they entered or exited a campus dining hall during dinner time.
They asked the men to rate how hungry they were on a scale of one to seven. Using these responses, the researchers selected 30 hungry and 31 satiated men to take part in the study.
The men were then asked to rate the attractiveness of 50 women of varying weights, all within a healthy range, who had been photographed wearing tight grey leotards and leggings.
Skinny women should want to go out to dinner with men since the men will find them more attractive as dinner progresses. Heavier set women might want to go bicycling with a guy to build up his appetite in more ways than one.
Using electroencephalogram (EEG) measurements of reactions to a large assortment of types of images shown for several seconds researchers found the minds of women react most strongly to erotic images.
Researchers at Washington University School of Medicine in St. Louis measured brainwave activity of 264 women as they viewed a series of 55 color slides that contained various scenes from water skiers to snarling dogs to partially-clad couples in sensual poses.
What they found may seem like a "no brainer." When study volunteers viewed erotic pictures, their brains produced electrical responses that were stronger than those elicited by other material that was viewed, no matter how pleasant or disturbing the other material may have been. This difference in brainwave response emerged very quickly, suggesting that different neural circuits may be involved in the processing of erotic images.
"That surprised us," says first author Andrey P. Anokhin, Ph.D., research assistant professor of psychiatry. "We believed both pleasant and disturbing images would evoke a rapid response, but erotic scenes always elicited the strongest response."
As subjects looked at the slides, electrodes on their scalps measured changes in the brain's electrical activity called event-related potentials (ERPs). The researchers learned that regardless of a picture's content, the brain acts very quickly to classify the visual image. The ERPs begin firing in the brain's cortex long before a person is conscious of whether they are seeing a picture that is pleasant, unpleasant or neutral.
But when the picture is erotic, ERPs begin firing within 160 milliseconds, about 20 percent faster than occurred with any of the other pictures. Soon after, the ERPs begin to diverge, with processing taking place in different brain structures for erotic pictures than those that process the other images.
I wonder if there is any trend as a function of age where the minds of older women might react less strongly to erotic images. I also wonder whether there is a difference with women on hormone suppressing therapies or who have had hysterectomies without replacement hormones.
Women rate erotic material as less appealing than men do. But their brains react as much to it as do the brains of men.
A great deal of past research has suggested that men are more visual creatures than women and get more aroused by erotic images than women. Anokhin says the fact that the women's brains in this study exhibited such a quick response to erotic pictures suggests that, perhaps for evolutionary reasons, our brains are programmed to preferentially respond to erotic material.
"Usually men subjectively rate erotic material much higher than women," he says. "So based on those data we would expect lower responses in women, but that was not the case. Women have responses as strong as those seen in men."
I would expect people with stronger sex drives to react more strongly to erotic materials. I wonder if one could use the EEG results like a biofeedback machine and train oneself to react more or less strongly to erotic materials. If one could train oneself to react more strongly would it provide any benefit for people who feel frigid or who get little pleasure from sex?
I'd also be curious to know whether a fast IQ test delivered after being shown images that elicit a greater brain response would show higher or lower mental ability. Do images that evoke stronger responses make the mind work quicker in general? Or do they divert mental resources away from problem solving?
Genetic variations in a dopamine receptor influence sexuality (same article here)
New evidence that individual differences in human sexual desire can be attributed to genetic variations has been revealed by a research group headed by a professor of psychology at the Hebrew University of Jerusalem. The findings are believed to have an impact on people’s understanding of their own sexuality as well as to how sexual disorders may come to be treated in the future.
An article on the topic appears currently in Molecular Psychiatry online. The study represents the combined efforts of researchers directed by Prof. Richard P. Ebstein, of Herzog Hospital and the head of the Scheinfeld Center for Human Genetics in the Social Sciences of the Psychology Department at the Hebrew University, and a research group headed by Prof. Robert H. Belmaker of the Psychiatry Division of Ben Gurion University of the Negev.
The article provides, for the first time, data that common variations in the sequence of DNA impact on sexual desire, arousal and function and lead to differences and diversity of the human sexual phenotype.
Did anyone previously not expect this to be the case? The press release gushes on about how this is a revolutionary discovery that will affect how we look at sexuality. Maybe that is true for some people who do not want to accept that genetic variations play a large role in determining our desires, dislikes, and behavioral tendencies and abilities. But I expect genetic roles in all sorts of aspects of cognitive function and in the peripheral nervous system. I just am eager and impatient to get to the details so we can work out the implications.
Self-reports on sexuality correlate with DRD4 dopamine receptor genetic variations.
In this latest study, the Israeli investigators examined the DNA of 148 healthy male and female Israeli university students and compared the results with questionnaires asking for the students’ self-descriptions of their sexual desire, arousal and sexual function. The results showed a correlation between variants in the D4 receptor gene – which is responsible for producing the dopamine receptor protein (DRD4) – and the students’ self-reports on sexuality.
Sounds like only 10% had moderate sexual desire and most were in the "depressant" category. I bet divorces are more likely between members of a couple who have radically different levels of sexual desire. Therefore genetic tests may eventually help to predict likelihood of marital success.
Interestingly, some forms of variants in this gene were shown to have a depressing effect on sexual desire, arousal and function, while other common variant had the opposite effect – an increase in the sexual desire score. The latter is believed to be a relatively new mutation, and it is estimated that it appears in Homo sapiens “only” 50,000 years ago at the time of humankind's great exodus from Africa. Approximately 30% of many populations carry the heightened arousal mutations, while around 60% carry the depressant mutation.
Did the migration from Africa take humans into areas where so much food was available that it was selectively advantageous to mate and reproduce more often?
Which are the populations that have a higher average level of sexual arousal? Does the level of sexual arousal correlate with other characteristics?
The discovery of a role for DRD4 in sexual arousal makes it a candidate target for drug development. Further research into the mechanism for how it causes this effect will likely lead to identification of other targets for sexual arousal drugs.
The investigators predict that as a result of their work, and other advances in neurosciences focusing on sexual behavior, a conceptual change will result, in which new therapeutic pathways will be developed for treatment of sexual dysfunctions based on a rational pharmacogenetic strategy. Additionally, the investigators note that many variations such as “low sexual desire” may be quite normal and not necessarily a product of dysfunction.
Viagra, Levitra, and Cialis are not enough. People want more ways to make themselves sex-crazed. Don't worry. The cheaper genetic sequencing gets the more genetic variations we'll discover that contribute to sexual arousal and the more targets for drug development that will be identified.
When it becomes possible to select the genetic variants offspring will get will more people select higher, lower, or medium sex drive genetic variations? I'm guessing women will want to give their daughters genetic variations that make multiple orgasms very easy. Will people want their kids to walk around constantly craving sexual experiences?
LA JOLLA, CA - It doesn't take John Wayne's deliberate, pigeon-toed swagger or Marilyn Monroe's famously wiggly sway to judge a person's gender based on the way they move. People are astonishingly accurate when asked to judge the gender of walking human figures, even when they are represented by 15 small dots of light attached to major joints of the body.
And not only that, when human observers watched the walking motion of a male so-called "point light walker," they were more sensitive to the female attributes when watching the next figure in the sequence. This suggests that the human brain relies on specialized neurons that tell gender based on gait, report researchers at the Salk Institute for Biological Studies in the May 21 advance online edition of Nature Neuroscience.
"Our judgment of gender can adapt within seconds," says senior author Gene Stoner, a neuroscientist in the Vision Center Laboratory at the Salk Institute. "The gaits of males and females may vary geographically or culturally and this mechanism allows us to adapt very quickly to local ways of walking," he adds.
How humans move reflects, in part, gender-specific differences in shape such hip-to-waist ratio and the like. Such inherent differences in gait might then be exaggerated by an individual to emphasize their gender. "Our new data suggests that there are neurons selective for gender based on these motion cues and that they adjust their selectivity on the fly," Stoner explains.
Although much work has been done on how the brain represents so-called low-level features, such as "redness" or "left-moving," scientists have been unable to put their finger on more abstract concepts such as gender. "We wanted to know whether gender is represented in a similar way to low-level visual features such as color, or if it is a more semantic concept such as good and evil," says experimental psychologist and first author Heather Jordan, a former post-doc in the Vision Center Laboratory and now an assistant professor at York University in Toronto.
Individual neurons in the visual cortex are finely tuned to certain attributes of visible objects such as the color red, a certain shape or objects moving in a specific direction. These specialized neurons reveal their existence through a telltale effect called adaptation. For example, if you stare at a red patch and then look at a neutral color you tend to see green. This "adaptation" reflects a mechanism in the brain that exaggerates differences between objects to increase the sensitivity and optimize the output of individual neurons.
I think the ability to recognize differences is something that one could enhance with thoughtful control of one's environment. What differences do you want to get better at recognizing?
These scientists expect to eventually identify a single neuron that activates for male gaits and another neuron that activates for female gaits.
"In the past, when adaptation in behavior was observed for specific features, neurophysiologists have subsequently been able to find individual neurons which fire only when they encounter this feature," says Jordan. "We think that the same is true for maleness and femaleness - that there are neurons in the brain that fire if, and only if, they 'see' a male gait and others that fire if, and only if, they 'see' a female gait, explains Jordan.
"We know lots about individual neurons that are sensitive to the direction of moving objects. But in this case, motion provides information about the structure of what is moving," says Stoner.
The mind compares gaits to recently seen gaits of other walkers. So you are more likely to be seen as masculine after the mind has just seen an especially feminine walk and you are more likely to be seen as feminine after the mind has just seen an especially masculine walk.
For their experiments, the Salk researchers morphed the gait of averaged male and female walkers -- resulting in varying degrees of "maleness" and "femaleness" .When the figure consisted of less than 49 percent male contribution, the observers reported seeing a figure that appeared female. Once there was more than 49 percent maleness in the figure, they reported seeing a figure that was mostly male. But these numbers were not stable: Viewing the gait of one gender biased judgments of subsequent gaits toward the opposite gender. "If you want to appear particularly feminine you should walk behind a very masculine-looking male and vice-versa," jokes Jordan.
If it all comes down to individual neurons then I'd expect an age-related degeneration in the ability to recognize male versus female gaits. Should just the right neuron die then one might lose the ability to tell apart males and females. Though the odds of losing that neurons are low the odds rise with age. Though perhaps there's a mechanism where another neuron can take over the job if the one neuron doing the job dies or starts to misfire.
Given that there are individual neurons that consolidate information for a large assortment of pattern recognition tasks one might have a better chance of identifying loss of function due to deaths of individual neurons if one measured a large number of capabilities (e.g. ability to tell colors apart, direction of movement, various types of shapes, and ability to identify male and female gaits) through time. Error rates might rise before total failure sets in.
Question: If you've just heard a speech from an obviously dishonest person then are you likely to think the next person is honest if they sound relatively less dishonest? If so, this might explain why politicians and political activists can get away with telling so many lies. They get compared to each other rather than to an absolute standard of honesty.
More generally, are there specific types of images or other stimuli one could present to one's brain before examining some evidence or issue as a way to increase one's ability to see a contrast and recognize key differences?
Women are wired up to detect which men like children.
(Santa Barbara, CA) – Women are able to subconsciously pick up cues in men's faces and use those cues to determine if they are attracted to the males for long-term or short-term relationships, according to a new study conducted by researchers at the University of California, Santa Barbara and the University of Chicago.
The study was published online today by the Proceedings of the Royal Society of London, the UK's national academy of science.
Men whose faces reflected an interest in children were intuitively perceived by woman as candidates for long-term commitments, whereas men whose faces indicated high testosterone levels were determined to be short-term prospects for relationships.
"Women are surprisingly accurate in being able to determine interest in children and testosterone levels," said James Roney, assistant professor of psychology at the University of California, Santa Barbara, who is the lead author of the paper. "Our data suggest that men's interest in children predicts their long-term mate attractiveness even after we account for how physically attractive the women rated the men," he said.
For the study, the researchers recruited male undergraduate students from a variety of ethnic backgrounds who were tested for testosterone and for their interest in children.
Researchers took saliva samples to measure testosterone levels. To determine interest in children, researchers showed the men a pair of pictures, one each of an adult and a baby. They were then asked which picture they preferred. Slightly more than twelve percent of the men expressed no interest in the baby pictures, while the rest expressed a range of interest, up to nine out of ten preferences for the infants.
The researchers then took pictures of each man, asking them to display a neutral expression. An oval frame was placed around each photo to focus attention on the faces and the photos were shown to undergraduate women from diverse backgrounds at UCSB.
The women were asked to rate the men according to whether they thought the men liked children, whether they appeared masculine, physically attractive, or kind. They were then asked to determine men's attractiveness as short-term romantic partners or as long-term partners for relationships such as marriage.
The men chosen as being most interested in children were also the same men who had expressed the most interest in children in the photo test. The women were also able to determine from their photos which men had high testosterone levels because they perceived the men as looking masculine.
Although women said they were attracted to the men who tested high for testosterone, an important factor in their attraction to men for a long-term relationship was their perception of a man's affinity for children, even after accounting for their perceptions of men's general kindness.
"The research suggests that men's interest in children may be a relatively under-appreciated influence on men's long-term mate attractiveness," Roney said.
What I'd like to see: Test women for estrogen levels and body shapes and see if the more feminine women are better or worse at detecting which men are more child-friendly. I bet the higher estrogen or perhaps high estradiol women are better at identifying good mates.
Also, are higher testosterone men more likely to get divorced?
Using positron emission tomography (PET) and Magnetic Resonance Imaging (MRI) Swedish researchers have found that the brains of homosexual women responded to pheromones in ways more like heterosexual men than like heterosexual women.
Lesbian and heterosexual women respond differently to specific human odours, a brain-scanning study has found. The homosexual women showed similar brain activity to heterosexual men when they inhaled certain chemicals, which may be pheromones, the researchers say.
"But our study can't answer questions of cause and effect," cautions lead researcher Ivanka Savic at the Karolinska Institute in Stockholm, Sweden. "We can't say whether the differences are because of pre-existing differences in their brains, or if past sexual experiences have conditioned their brains to respond differently."
Anyone surprised?
Lesbian and heterosexual women showed different patterns of brain activity while sniffing AND and EST, the study shows.
While smelling AND and EST, the brain activity pattern for lesbian women was closer to that of heterosexual men than heterosexual women, Savic and colleagues note.
Previously homosexual men and heterosexual women were found to have even greater similarity in their brain patterns when exposed to these compounds.
Lesbians didn't react in their anterior hypothalamus while heterosexual women did.
The results showed that while a part of the brain called the anterior hypothalamus -- which is linked to sexual behavior, among other things -- tended to light up in the straight women, the lesbians showed no reaction.
On the other hand, lesbians tended to react to male as well as female hormones in the part of the brain that handles routine odors.
We have preferences and desires that come up from deep in our subconsciouses which we have little control over. We have some control over how we react to the desires. But little control over the nature of the actual desires.
Men become more jealous of dominant males when their female partner is near ovulation, researchers at the University of Liverpool have found.
Previous studies have found that women's preferences for male physical appearance vary according to their fertility status. During ovulation women tend to find masculine looking men more attractive and prefer their voices and odour. During this fertile phase women are more likely to have an affair with a masculine-looking man, as their features are linked to high testosterone levels, demonstrating good genetic qualities that can be passed on to offspring.
New research at the University has found that men sense this preference shift in their female partners and find masculine men more threatening during their partner's most fertile phase. Rob Burriss and Dr Anthony Little, from the University's School of Biological Sciences, also found that men only behave in this way if their female partner does not use oral contraception – and is therefore more fertile.
Images of male faces that were either high or low in dominant features, such as a strong jaw lines and thinner lips, were shown to male participants who provided ratings of dominance for each image. A dominant person was defined as someone who looked like they could 'get what they wanted'.
Participants were asked to provide information on whether or not their female partner used oral contraception and the date of her current or previous menses. Male participants whose partners did not use oral contraception and were near ovulation rated masculine faces more dominant than those participants with partners who did use oral contraception and were not near ovulation.
I think of Ray Davies and the Kinks singing "I'm an ape man, I'm an ape ape man, I'm an ape man. I'm a King Kong man. I'm a voodoo man. I'm an ape man". Do not be fooled by all the technological civilization you see around us. We are still primitive products of natural selection.