Science of Love, Sex, and Babies

Who’s Turned On By Pregnant Women?

Posted in parenting, pregnancy, psychology, science, sex by jenapincott on September 26, 2011

 

Early one evening late in my second trimester of pregnancy, I was standing in the dairy aisle of the grocery store, with one hand on my back and the other over the kicking baby in my distended belly. A young man approached me, initiated a conversation about the World Cup, and, casually, asked me if I’d like watch the game with him that weekend. “You’re pretty!” he whispered. I was shocked.

I wasn’t putting out a sexy vibe. (Not at all.) I had assumed that any male attention I receive in late pregnancy, including that from my husband, would be friendly, not sexual. Why would a man who is not the expectant father think pregnancy is sexy? But then other women told me similar stories about how they got hit on in third trimester. So I decided to look into it, and it turns out that a study on sexual attraction to pregnancy has recently come out.

A team of Swedish and Italian doctors, led by Emmanuele Jannini and Magnus Enquist, recruited nearly 2,200 men who had joined online fetish groups such as alt.sex.fetish and alt.sex.fetish.breastmilk. They presented a questionnaire that asked the respondents questions about their preferences for pregnant and lactating women. The survey also asked for the sex and age of each sibling, and whether the sibling is a full sibling or not (half-sibling or adopted child). Most respondents reported both a pregnancy and a lactation preference. The average age at which respondents became aware of their preference was about 18 years.

What Jannini and Enquist and their colleagues were searching for was evidence that there was something special about the upbringing of men that are secually aroused by pregnancy. They knew that a specific stimulus early in life can elicit sexual behavior when theat animal reaches sexual maturity. For instance, goats that are raised by sheep are sexually aaroused by sheep only. This is called sexual imprinting.

Is it possible that boys that are raised by women who are pregnant for much of their childhoods are unusually attracted to pregnant women?

It turns out, what’s good for the goat is good for the guy. The more exposed a man was to his mother being pregnant and breastfeeding when he was between 1.5 and 5 years old, the more likely he is, as an adult, to be sexually attracted to pregnant and breastfeeding women.

A younger sibling is the key to early exposure. The respondents who eroticized pregnancy and breastfeeding had significantly more younger siblings than expected by chance. Respondents with one sibling were older than their sister or brother in 66 percent of cases. Interstingly, siblings born of a different mother does not appear to be related to respondents’ sexual preferences. Only a boy’s own pregnant mother seemed to leave a sexual imprint.

Freud’s “oedipal phase,” from about 3 to about 5-6 years of age, only overlaps partially with the sensitive period suggested by this study’s data, the researchers are careful to point out. Sexual imprinting is different in that it’s motivated not by sexual drive but because the individual learns what’s normal during a sensitive phase of development and later seeks sexual partners that resemble his (or her) own parents.

What does this mean for women who are pregnant or plan to be pregnant? It means you may be able to predict how attracted your partner will be to you in late pregnancy. Does he have sibling born within five years after him? If so, he’s likelier to be turned on by your pregnant self.

As for the guy I met in the dairy aisle, I’d wager he had a younger brother or sister. I’d bet more on getting this right than the winner of the next World Cup.

 *If you like this blog, click here for previous posts and here to read a description of my most recent book, Do Gentlemen Really Prefer Blondes?, on the science behind love, sex, and attraction. If you wish, check out my forthcoming book, available October 11,  Do Chocolate Lovers Have Sweeter Babies?: The Surprising Science of Pregnancy. 

 

 

 

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Do Beautiful Babies Become the Most Beautiful Adults?

Posted in pregnancy, psychology, science by jenapincott on August 18, 2011

The Gerber baby, then and now

Forgive me, I believe my one-year-old is the cutest baby ever. Yes, yes, mothers are biased about their own children.  As I detail in my new book, certain reward circuits “light up” in parental brains only when looking at their own offspring.  But objectively — objectively! — my daughter is adorable.

The little one has “Gerber baby” features:  a bulbous forehead, big eyes, luscious cheeks and thighs (and curls). Babies with these qualities are rated as cuter than those with sunken foreheads, small eyes, and large or long chins.  Adults smile and gaze longer at them. Attractive infants are perceived to be more sociable, easier to care for, and more competent than their homely peers. They inhibit aggression in adult men. They receive more nurture.

Our baby thrills to the attention, and my husband and I have started to worry that being cute might not lead to anything good.  I have a theory that ugly ducklings and tomboys grow up to have richer inner lives.  I don’t want a princess.

We want to know:  Do the cutest babies turn out to be the most attractive adults?

Conveniently, a recent study by psychologists Gordon Gallup Jr, Marissa Hamilton, and their colleagues addresses this very question. (I love these whimsical studies; they’re motivated by genuine curiosity.) The presumption is that physical attractiveness remains stable over time.  This has been proven in childhood onward:  attractive ten-year-olds are likelier to be attractive adults.  (Another study found that adult attractiveness can be predicted as early as age five).  But until now no study had tracked attractiveness from infancy.

It’s interesting, how the psychologists went about it.   They sifted through high school yearbooks and found forty graduating seniors who featured photos of themselves as infants. Then they asked several hundred college students to rate the the individuals — in infancy and in adulthood — for attractiveness.

The upshot?

There was no correlation between attractiveness in infancy and (young) adulthood. Some ugly ducklings turned into swans, some baby swans become ugly ducks.  Some gawky, awkward babies remained that way into their senior year of high school.  And some beautiful babies kept their glow through the years. This was true of males and females alike.  Cuteness — or homeliness — in infancy does not predict future attractiveness.

The study included an interesting side finding:  While the raters were likely to agree about which infants were attractive, they often disagreed about which eighteen-year-olds made the cut. Why? The gold standard of baby beauty — the forehead, the eyes, the thighs — is universal. These preferences are hard-wired in us to elicit care and protection, while the perception of adult beauty is tempered by culture.

Cute babies are universal positives.  In this light, it’s OK that mine gets attention now.  The future will be much less predictable.

 

 *If you like this blog, click here for previous posts and here to read a description of my most recent book, Do Gentlemen Really Prefer Blondes?, on the science behind love, sex, and attraction. If you wish, check out my forthcoming book, Do Chocolate Lovers Have Sweeter Babies?: The Surprising Science of Pregnancy. 

 

Do You Live Less if Your Mom Was Stressed?

Posted in parenting, pregnancy, psychology, science, sex by jenapincott on August 12, 2011

Not long ago, a handful of scientists at the University of California at Irvine were curious about why some people live longer than others — even within groups that have similar ethnic and educational backgrounds, demographic and disease risk profiles, and are exposed to similar stressors in life.  At heart, they know the question is impossible to answer.  People are complex. The effects of life events on our genes—what we eat, what we breathe, who we love and how well we’re loved, and so on —are impossible to isolate.

But the scientists had a hunch that some of us had a bad start —beginning in the womb — because our mothers were highly stressed during pregnancy.   There’s an avalanche of evidence that women who are under extreme duress in pregnancy have kids who have shorter attention spans, lower IQ, memory deficiencies, and health problems.  

Could prenatal stress also set a baby’s life expectancy clock to tick faster?

One way to find out is to look at the genes of people whose mothers were extremely stressed during pregnancy. In each of our cells are DNA-protein complexes called telomeres, which cap the end of chromosomes.  Telomeres are like the plastic bit at the end of a shoelace to keep it from unraveling. Each time a cell divides, they become a little shorter. This makes telomeres something of a longevity marker. People with long tips at the end of their DNA strands tend to live longer than people who have short tips.  It doesn’t matter how long your shoelace is; what counts is the integrity of the cap.

In the UCI study, researchers recruited volunteers in their twenties. Some were selected because their mothers experienced a horrid event during pregnancy.  The scientists weren’t looking for the normal pregnancy stressors — work-life balance, weight gain, fretting about the baby’s health, and so on. They meant extreme stressors: a sudden divorce, a death in the family, a natural disaster, and physical or emotional abuse.

What they found is disturbing.

Compared to the control group (whose moms had a relatively stress-free pregnancy), people exposed to their moms’ extreme prenatal stress had significantly shorter telomeres.  By our mid-twenties, most of us lose about 60 base pairs of telomere length annually.  Not so of people who were exposed to extreme prenatal stress — they lose drastically more telomere length each year. The men had 178 fewer base pairs on average (equivalent to 3.5 additional years of aging).  Women had a shocking 295 base-pair deficit  (5 years of accelerated aging). It seems that a mother’s prenatal stress hits her daughter harder than her son.

How does this happen?  During pregnancy, stress may alter blood flow, oxygen, and glucose metabolism between mother and baby. High levels of the stress hormone cortisol from the mother flood the placental barrier. Excess cortisol may also slow down in the production of telomerase, an enzyme that acts as a repair kit for telomeres. Telomerase adds telomeric DNA to shortened telomeres. It regenerates our cells and tissues.  Like a fountain of youth, telomerase gives back what time takes away.

So what if you’re on a telomerase-less trajectory?

Here’s the big relief:  Your clock doesn’t have to keep ticking so quickly, even if it has been set that way before birth. There’s strong evidence that lifestyle changes can amp up telomerase production. One study found that stress management, counseling, and a healthy diet are associated with higher telomerase activity.  Another found that meditation turns up the telomerase dial.  

In the research community there’s much interest in the idea that, by maintaining our telomeres, gene therapy might someday reverse or prevent aging if started early enough.  Is it possible? As a measure to conceal the abuses of youth, teens could freebase on telomerase. 

Oh, the ways to stress out Mom.

 

 *If you like this blog, click here for previous posts and here to read a description of my most recent book, Do Gentlemen Really Prefer Blondes?, on the science behind love, sex, and attraction. If you wish, check out my forthcoming book, Do Chocolate Lovers Have Sweeter Babies?: The Surprising Science of Pregnancy. 

 

Assorted Trifles (from the science of love, sex, and babies)

Posted in news, parenting, pregnancy, psychology, science, sex by jenapincott on August 4, 2011

Research is like a box of chocolates; you never know what you’re going to find. An assortment of studies on love, sex, and babies — fresh from the lab.

Scientists found that men whose ring fingers are longer than their index fingers are likelier to have longer-than-average penises, at least among Korean men whose flaccid genitals were stretched under anesthesia. Studying the files of women who were raped in 1999-2006, French researchers discovered that there were fewer incidences of living sperm than in rape victims in previous generations, which supports the theory that sperm quality is declining. Women are likelier to get pregnant if they ovulate from their right-side ovary, visible by ultrasound, especially after two consecutive left-side cycles, inspiring women undergoing fertility treatment to desire a L-L-R pattern. Among women whose fetuses inexplicably died in third trimester, 64 percent (392/614) had a premonition before their doctors told them. They described a feeling of discomfort, of a strange unease; that they understood subconsciously that the baby would die. Many described how they dreamed of dead relatives and of death on the night the baby probably died. A recent fMRI study reported that women who had given birth vaginally exhibited greater activation in brain regions involved in the regulation of empathy, arousal, motivation and reward circuits in response to their baby’s cries compared to those who had not. Women who snore loudly and frequently were at high risk for low birth weight (relative risk = 2.6 [95% confidence interval = 1.2-5.4]), and fetal-growth-restricted neonates. The success of an IVF transfer may in part be predicted by how much glucose medium an embryo “eats” on days 4 and 5. On Day 4, female embryos consume significantly more sugar than males.

Are Extroverts That Way Because of Their Fathers?

Posted in parenting, psychology, science by jenapincott on June 24, 2011

All babies demand their parents’ attention. But how many 11-month-olds demand the attention of strangers, too? Ours does. We bring her to restaurants and she scans the room until she catches someone’s eye. My husband will pick her up and carry her over to her admirer, whom he’ll chat up. Dad’s a socialite, Baby’s a socialite. Mom reaches into her bag and pulls out a book.

You might think your baby’s social confidence depends on the usual mix of genes and environment. This is true, but it might not be the whole truth. There’s also evidence that children rely more on their father’s social signals than their mother’s. That is, socially confident dads may have more socially confident kids. Socially anxious fathers may have more socially anxious kids. It matters less whether Mom is a social butterfly or a bookworm.

The bulk of the research on paternal influence on sociability comes from Susan Bogels, a professor in Developmental Psychopathology at the University of Amsterdam, and her colleague Enrico Perotti. In a recent review, Bogels and Perotti draw on research that suggests a dominant paternal role in their children’s sociability, including:

In one study, 9-11-year-olds were asked to imagine themselves in a series of stories involving strangers, while their mother and father responded in a socially anxious or socially confident way. Children who had socially anxiety were more influenced by their father’s reaction more than their mother’s.

A study of boys with behavioral problems, including social anxiety, found that fathering, but not mothering, predicted the children’s level of inhibition. In another study, secure infant-father attachment, but not infant-mother attachment, predicted stranger sociability among toddlers.

• Among kids enrolled in treatment for social anxiety, those whose fathers had high levels of social anxiety had a worse outcome (were more socially anxious) than those whose mothers had it. Socially anxious mothers are not as likely as socially anxious fathers to make their kids less sociable.

So here’s the mystery: Why would fathers, who have less to do with childrearing than mothers, have more influence on their children’s sociabilty?

It’s an interesting question, and Bogels and Perotti have an interesting answer. “In the course of human history,” they write, “fathers specialized in external protection (e.g. confronting the external world outside the clan or extended family), while mothers provided internal protection (e.g. providing comfort and food). Therefore, children may be hardwired to respond more to their father’s signals about the social world than the mother’s, and adjust their behavior accordingly.

Through the ages, it benefited children to rely more on their father’s than mother’s cues about whether unfamiliar people are generally hostile or cooperative. Of course, gender roles have long since changed – moms go out into the world every day and meet strangers – but our instincts haven’t.

So the lesson here is that fathers orient their children outward, mothers inward. When researchers observed a group of toddlers taking swimming lessons, they took note of where the parents stood. Mothers protectively stood in front of their babies, encouraging face-to-face interaction with them. Fathers stood in back, so that their children would face their social environment.

∞∞∞∞∞∞∞∞∞∞∞∞

Bogel and Perotti’s review includes a fascinating aside about paternal roughhousing and its effect on children’s social confidence. Rough-and-tumble play – I think of my husband tossing our infant in the air, spinning her around, throwing her over his shoulder, as she giggles and squeals- gets a scientific seal of approval.

Here’s why. Kids learn to associate physiological arousal – a racing heart, tight chest, spinning head – with fun instead of fear, which crosses over into other social interaction. Roughhousing also involves behavior – being aggressive, sneaky, teasing, playful – that requires different roles and different responses, and forms a basis for social skills. By pinning kids to the ground, swinging them like sacks of potatoes, attacking them and getting attacked – fathers make their progeny more confident.

∞∞∞∞∞∞∞∞∞∞

So many questions. If we have evolved so that fathers strongly influence their children’s sociability, what does this mean?

It means that fathers who are socially anxious themselves are likelier to have kids who are not socially confident. If a kid suffers from severe social anxiety, perhaps his or her father should be involved in the kid’s therapy or get therapy himself. But what about kids who don’t have fathers who are involved or live at home? How do mothers compensate? And what about gender? So far there is no evidence that boys are more susceptible to the father’s signals than are girls, but is this really so? And what about other male figures – male teachers, older brothers, uncles, grandfathers – are they equally influential? At what age is paternal influence on sociability strongest? And are paternal genes more influential here too?

Further research is warranted. Until then, we can wonder about the great socialites in history – the Jackie Os, Andy Warhols, Paris Hiltons, Truman Capotes, Gloria Vanderbilts, Nan Kempners, and Ivana Trumps. Did they get it from their dads?

 

 

 

Are Men Likelier to Cheat When Their Partners are Pregnant?

Posted in parenting, pregnancy, psychology, science, sex by jenapincott on June 13, 2011

It’s bad enough that  Congressman Anthony Weiner had been taking photos of his naked self and sending them to women who weren’t his wife.  It’s worse when we learn that his wife is three months pregnant.

Aha, that it!, some cynics claim.  Now that Weiner’s oats are sowed, he’s exploring new (and, if the twittering teen rumor is real, very green) pastures.  It’s only natural.

But is it?  Are men really more likely to cheat when their wives are pregnant?

Turns out, the answer is that it depends on the man.

Reviewing the studies of pregnancy and sex, it seems there are three categories of expectant fathers. 

  • Type Z cheats or wants to cheat (the Weiners). 
  • Type Y desires his pregnant wife more than ever.
  • And then there’s Type X  — a man who has a decreased sex drive and a lower risk of cheating on his wife.

The bad news is that at least one study found that, yes, the risk of a given man to cheat on his wife increases during pregnancy, even if he is otherwise satisfied in his marriage.  His reasons? He may feel ambivalent about the pregnancy or the changes that go with it. His partner, especially in her first and third trimesters, may not feel like having sex.  Her sex drive may diminish. She may think her body is unattractive.

(Incidentally, bodily dissatisfaction happens to be the number one reason why most women have less sex during pregnancy.  Most of us think pregnancy is a turn-off for men.  That’s a misconception.)

But here’s the good news for pregnant women.  Fact is, many men — the majority as found in this study — desire their pregnant partner even more over the course of the pregnancy, even if they aren’t having as much sex as before. They find her as physically attractive as she was prepregnancy, if not more so. These are usually the Type Y guys. Another study found that, while couples had sex less frequently in third trimester, the only circumstances under which men change their sexual behavior is if they are older or worried about the safety of the fetus. (Note:  Sex does not raise the risk of miscarriage in pregnancies that are not high risk.) Otherwise, men desire sex with their wives just as much.

From an evolutionary perspective,this makes some sense.  Women benefited from having their mates around to help support them through pregnancy and childrearing. Sex helps men stick around.

The Type X expectant father – the one with a low sex drive and a lower risk of infidelity – may overlap with Type Ys. These are men who, at some point over the nine months, are afflicted with pregnancy symptoms:  nausea, weight gain, mood swings, fatigue, even vomiting. Hormones are the culprit.  These men have higher levels of prolactin, a hormone associated with sluggishness, weight gain, and bonding and parental behaviors.  Their testosterone levels plummet, making them less combative and sexually aggressive.

There’s an upside to Type Xs. It turns out that these faithful, fattening men display the most fatherly behavior when the baby arrives.  As new dads, they’re more likely to hear and respond to their infant’s cries.  They’re more compassionate and tolerant.  They make better fathers.

One might speculate that Weiner’s Type-Z behavior while his wife is pregnant doesn’t bode well for Weiner’s fathering instincts. It’s clear that if any hormone is raging in the man, it’s testosterone — not prolactin. He is probably not sharing his wife’s morning sickness and taking turns with her over the toilet.

There’s no crime in what Weiner has done; he’s just another politician more interested in power more than paternity.  But he is making us a little nauseous.

 *If you like this blog, click here for previous posts and here to read a description of my most recent book, Do Gentlemen Really Prefer Blondes?, on the science behind love, sex, and attraction. If you wish, check out my forthcoming book, Do Chocolate Lovers Have Sweeter Babies: Exploring the Surprising Science of Pregnancy. 

 

Eternal Sunshine of the Springtime Mind

Posted in magazine articles, media, science by jenapincott on May 28, 2011

Warm weather isn’t just good for the flowers. Sunny days have been linked to higher stock returns, and touching a warm object can make people more generous. My article in this weekend’s Wall Street Journal.

How big is your limbal ring?

Posted in news, psychology, science, sex by jenapincott on April 30, 2011

Of all the qualities that give an attractive person an edge, here’s one you’ve likely overseen:  the limbal ring,  the dark circle around iris.  The limbal ring is the line that separates the colored part of the eye from the white (the sclera).   

It’s completely unconscious, the way we all judge others’ limbal rings. In the 20 milliseconds or so it takes to assess a person’s attractiveness, you’re factoring in the size and shade of the limbal rings. The bigger and blacker they are, the more attractive the eyes. People with the prettiest eyes have the most prominent limbal rings.  

This, anyhow, is the upshot of a recent study by Darren Peshek and his colleagues at the Department of Cognitive Science at the University of California at Irvine. The researchers showed volunteers eighty pairs of male and female faces.  Each pair of faces was identical except the eyes: one had dark limbal rings and the other had no limbal rings.  The volunteers were asked to pick which face was more attractive and to indicate their degree of preference.

Men thought women with the dark limbal rings were more attractive than those without, and women thought the same of men with dark limbal rings.  Men and women also judged faces of the same sex as more attractive when the limbal rings were large.

Looking into my baby daughter’s eyes, I see the blue of her iris is framed by a thick black limbal ring.  The contrast makes the white of her eyes so white they look blue. The very young have the thickest, darkest limbal rings.

Which is exactly the point.  The limbal ring serves as an honest signal of youth and health-desirable qualities, reproductively speaking. The ring fades with age and with medical problems.  It’s thickest from infancy through the early twenties.  A thick, dark limbal ring may make us appear younger.  It makes the whites of the eyes whiter.  This might be why so many people think light eyes are so sexy:  the limbal ring, when present, shows up more.  

There are so many ways to fake the appearance of youth. You can wear makeup and wigs and get tummy tucks, plastic surgery, Botox, and boob jobs.

But a fake limbal ring?

Yes, this too. Long ago, Japanese schoolgirls discovered the edge a limbal ring can give you by wearing “limbal ring” contact lenses. They make the eye look bigger and more defined. And while you’re eyeing these contacts, you might as well buy a set that expands your pupils too. Big, dark, dilated pupils signal emotional arousal. They, too, act on the unconscious favorably.

The limbal ring is well-named. Limbis means border or edge, and it’s related to limbic, meaning emotion or drives. The limbal ring, seen from inches away, is an intimacy zone. Don’t flirt until you see the whites of their eyes.

Do Brothers Stall Their Sisters’ Sex Lives?

Posted in parenting, psychology, science by jenapincott on March 20, 2011

Nearly eight months ago I gave birth to a baby girl. The child is now a seam-popping twenty-plus pounds. Infants, they grow so quickly it’s creepy — my thoughts fast-forward through her teething years to the teens, and I’m terrified. Problem is, my family lives in New York City where children want to be adults. The weenies of tweens should stay in their jeans, but all too often they don’t.

The onset of girls’ sexual maturity depends a lot on the social environment — peers, culture, and so on. A recent study by Australian behavioral ecologists Fritha Milne and Debra Judge found that it especially depends on the family environment, and not in the expected ways of curfews and chastity pledges. Sure, if you’re a teenage girl your parents might hold you back from trying to lose your virginity. So may your grandparents and any other authority figure in your family.

But so might your little brother.

Milne and Judge recruited nearly two hundred women and seventy-six men, all living in or around the city of Perth, Australia, and asked them questions about their family lives and sexual development. The results were that girls with only younger brothers lost their virginity an average of more than a year later (at age 18.3) than girls with younger sisters only. Girls with both younger brothers and sisters lost it nearly two years later on average (age 19.3) than girls with no younger siblings. Younger sisters alone had no impact.

The chastity effect only applied to girls with younger brothers. Having a big brother (or sister) didn’t make a girl any less likely to hold onto her virginity, yet another strange pattern emerged. This one involved the girls’ physical maturity.

The more older brothers a girl had, the later she got her first period. Girls with only elder brothers got their first visit from “Aunt Flo” up to a year later (at age 13.6) than girls with older sisters or no older siblings (age 12.7). (This is meaningful given that breast cancer and other conditions are related to earlier menstruation.)

Elder brothers delay physiological maturation, while younger brothers delay behavioral maturation.

What’s going on?

Trained as behavioral ecologists, Milne and Judge took a look at the big picture. Daughters are often caregivers. Historically, as has been found in traditional societies, a woman with daughters as first- or second-born children has a larger family than a mom whose first children were sons. Elder daughters take care of younger siblings, which frees up Mom to keep popping them out. Boys historically required more resources than do girls, which made big sister’s contributions even more important. As a result, these helpful elder daughters experience a delay in starting their own families. In the modern world where women don’t usually start their families until their mid-twenties on average, this is no problem, but in the past females with brothers may have had fewer children over their lifetimes.

The bigger mystery is what’s actually behind Big- and Little Brother’s stalling effect on their sisters’ sexuality. This is unknown territory, so Milne and Judge tread lightly here. The safest theory is that the delays are behavioral. Girls with little brothers lose their virginity later because they’re too busy taking care of their siblings to have love lives of their own. Perhaps little brothers, who are slower than female siblings to develop and reach puberty, keep their elder sisters in a more childish mindset. Or perhaps the stress of care-giving slows down puberty.

The researchers should also consider a much more surprising yet equally plausible theory: brothers send out chemical cues (pheromones) in their sweat that inhibit their sisters’ sexual development. Odd as it sounds, this would explain the perplexing finding that girls with older brothers get their first periods later than their peers. And, it appears, so do girls who grow up with their biological fathers in the household, compared to their peers with absent dads. Several studies, including here and here and a large one at Penn State that involved over nineteen hundred college students, came to this conclusion. (Interestingly, the same study found that girls growing up in homes with males unrelated to them got their periods earlier than average.)

The sweat-stifles-sexuality theory isn’t as far-fetched as it sounds. Other animals — rodents, for instance — use pheromones to modulate sexual maturity and fertility in a population. Over the years, a girl would inhale chemical cues in fraternal sweat — think of all those sock and armpit odors. Those chemicals would hit the hypothalamus of her brain where sex hormones are produced, and slow down the works. Puberty strikes a little later. Evolutionarily speaking, the result is that a girl could stay in the family nest longer without conflict. The risk of incest is reduced.

So should I try for son now? Truth is, the data applies to populations, not individuals. There are no guarantees; these are just interesting findings that deserve more research. Moreover, I’m in over my head right now with my baby girl’s teething and feeding challenges. Sure, I’ll want preserve her girlhood for longer than a New York minute. But I also need to preserve my sanity

 

Are sexually motivated men responsible for the recession?

Posted in news by jenapincott on December 9, 2008

babeinpileofmoneyenhancedOne theme I discuss in BLONDES is that male economic resources are related to reproductive success. Consumption — of cars, clothes, vacation houses, horses, holidays, bling — is how guys show off their economic power, and in past years consumption in the U.S. has skyrocketed. So, incidentally, has the infidelity rate among both men and women.
According to a new study by Daniel Kruger a the University of Michigan, men with strong “mating intentions” do indeed spend more and save less than their less sexually motivated peers. Kruger and his colleagues conducted a random telephone survey, asking men to report their expenditures and sexual histories. Indeed, regardless of age, marital status, and education, guys who spent more than they saved — and who spent more than they earned (thanks to cheap and easy credit) — reported having more sexual partners and a desire for higher numbers of sexual partners than their more monogamous peers. The 25 percent of men who were fiscally conservative had an average of three sexual partners in the past five years, and only desired one partner in the next five years. The guys with the highest levels of conspicuous consumption doubled those figures.
The dirty little secret is that our economy runs on the male impulse, honed by thousands of years of evolution, to spend as a way to show status, which is in turn related to reproductive success. Imagine — what would happen to global markets if women were deliberately disinterested in the goods men have to offer?

Here’s a theory: did cheap and easy credit make it easier for men to attract more women than they would otherwise? Did low interest rates, easy mortgages, and generous credit lines inadvertently increase the divorce rate — or aid and abet infidelity? If so, could a recession actually mean more monogamy?

Comments welcome.

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