I got a boob job two years ago. My best friend, seeing the results, wanted one, too. When she realized she couldn't afford it, she started making snide comments about women who get them. Recently, a guy was hitting on me at a party, and she started flirting with him and asked, "Do you think I need a boob job?" and told him I'd gotten one. I was shocked. I'd like to say something to her, but she's the louder part of my friend group, and I'm unsure how.

--Disturbed

Self-defense for men is karate or maybe Krav Maga. For women, it's ducking mean remarks.

Many people have a romanticized view of women as the sweet, ever-nurturing "better angels of our nature." That's a major myth, but it continues to have traction due to the nature of female rivalry, which is much like slow-acting poison gas. (It's often hard for a woman to recognize she's been dosed...till she's writhing on the floor like a goldfish sucking in its last desperate breaths.)

While from boyhood on, guys tend to relish competition and are openly aggressive (like when one socks another in the jaw), psychologist Anne Campbell describes female aggression as "indirect" and "covert" (sneaky and hidden). She believes women evolved to compete this way to avoid physical harm that might have damaged their ability to have or care for children.

Common sneaky ladywar tactics include weaponizing a group of women against a targeted woman by spreading nasty gossip about her and rallying the coven to ostracize her. In the presence of a man or men, one woman will try to undermine another woman's mate value by revealing her supposed hussyhood or trashing her looks -- as you experienced.

Men tend to prefer natural breasts (though their eyes go boi-oi-oing! at the big, pert fakeuns). Your "best friend," spotting that a guy seemed into you, performed the vital public service of informing him your bodacious boobs are, in fact, siliconey islands.

Why would she do this? Well, unbeknownst to you, you violated an unspoken rule of female society by amping up your appeal to men via Boob Fairy, M.D.: openly competing with other women. It's the "openly" part that's the problem. Psychologist Joyce Benenson explains that, in contrast with "the constant male struggle to figure out who is better, faster, smarter, or otherwise more skilled," girls and women enforce "equality" among themselves and resent and punish women who stand out.

"Should a girl appear superior, even accidentally," she is guilty of a crime against the rest and "faces social exclusion." This carries through to adulthood, with the thinking (summed up by Benenson): "Nice women don't try to outdo their female peers."

Of course, women do compete. But, Benenson notes -- per interviews with hundreds of women by various researchers -- women deny they compete with one another, even to themselves. This subconscious self-deception -- "a woman's honest belief that she never competes with other females" -- allows her to do just that without any pangs of conscience getting in her way.

That's one reason why confronting this woman about what she did might be problematic. Additionally, research by evolutionary psychologists Tania Reynolds and Jaime Palmer-Hague suggests your standing up for yourself -- telling this woman her behavior was out of line -- could be portrayed by her (to other women in your circle) as your victimizing her! Thus putting a big stain on your reputation!

Compared with "traditional forms of gossip" (the sort readily perceived as catty and mean), women's disclosures of a friend's hurting their feelings (kindness "violations") get a pass, Reynolds and Palmer-Hague observe. They are "relatively trusted and approved," suggesting women have "a social blind spot" to a tool used to trash the reputation of other women. Reynolds explained to me via email: Basically, if a female friend says about another woman, "'You wouldn't guess how mean Mary was to me the other day,' you're less likely to recognize this friend's disclosure as gossip."

In their research, disclosures like this "effectively tarnished ... social opportunities" of the women they were made about. "Participants evaluated women who treated their friends poorly as immoral," avoided having them as friends, and wanted to "warn others about their bad character."

You might decide to say something anyway: gently tell this woman you prefer to keep news of your boob job unbroadcast. Note that even this approach could be turned into ammunition against you through a "victimhood" story she might tell.

Consider whether you have the social and emotional capital to bear the potential costs -- while factoring in the psychological cost of just sucking it up and saying nothing. Ultimately, though many women are nothing but supportive of other women, it's wise to remain mindful that, well, behind every beautiful woman is a crowd of other women looking to push her into a shed and padlock the door.

For pages and pages of "science-help" from me, buy my latest book, "Unf*ckology: A Field Guide to Living with Guts and Confidence." It lays out the PROCESS of transforming to live w/confidence.

I'm good friends with an ex. She's a great person, but we just don't work romantically. For two years, I've been seeing a woman I love and want a future with. She initially said she was fine with my friendship with my ex. Two months ago, she said she was uncomfortable with it and it might even be a deal breaker. How is it fair for her to decide this now?

--Don't Wanna Dump A Friend

There are a number of things absent from straight men's friendships with other men -- namely how two dudes boozing it up together on the couch never leads to anyone's bra being yanked off and flung onto the ceiling fan.

Two years ago, your girlfriend did say she was okay with your friendship with your ex. So, your feeling like you've been played is understandable -- but probably driven the (very common!) tendency to overestimate our ability to engage in reliable "affective forecasting." "Affect" is researcher-ese for emotion, and affective forecasting involves predicting how some future event will make us feel. Research by psychologists Daniel Gilbert and Timothy Wilson suggests we're pretty bad at foreseeing what we'll ultimately want and how happy or unhappy it will make us down the road.

Our guesses about how we'll eventually feel are colored by our circumstances and preferences at the time we're making a prediction. For example, before your girlfriend was very attached to you, she might've believed your friendship with your ex was (and would keep being) no biggie. As her love for you grew, the stakes of losing you loomed large in a way they didn't back in the cool light of "Mmmkay, let's see where things go with Mr. (Possibly) Right."

Tell her you want to understand her feelings -- and do something few people do when they have a goal of their own in mind: Listen fully and open-mindedly (as opposed to giving the appearance of listening while mentally cataloging all the fantastic points you'll make). Hearing her fears could help you empathize with her -- which should make her feel understood. Explain why she has nothing to worry about (uh, assuming that's the case). You might also actively reassure her: regularly do stuff to show how much you love her. Ultimately, however, you might have a big ugly choice to make if you can't get your girlfriend to stop seeing your friendship with your ex as something along the lines of Wile E. Coyote getting the night watchman gig at KFC.

For pages and pages of "science-help" from me, buy my latest book, "Unf*ckology: A Field Guide to Living with Guts and Confidence." It lays out the PROCESS of transforming to live w/confidence.

I'm a female college freshman. I was always told that college was the ideal place to find a partner. Disappointingly, there are many more women than men in my year. I want to date a guy and get to know him before having sex, but most of the women seem to hook up right away. I worry that I can't compete with them, as I'm not comfortable with that trend of behavior.

--Old-Fashioned

Your body is your temple! Unfortunately, much of your female competition on campus sees theirs that way, too -- only their temple's Angkor Wat, where there's a dude outside admitting the crowds with a clicker.

Colleges have become degree-granting hookup-aterias. There are a number of reasons for this, but you point to a biggie in your email: Over the past 40 years, there's been a growing imbalance of women to men on campus. At the end of the 2020-21 academic year, women made up 59.5% of college students -- "an all-time high" -- to men's 40.5% (per The Wall Street Journal). That's almost three women for every two men...on average. Some campuses have an even worse guy-girl gap.

Though we're all walking around with pocket supercomputers (which women can use to click their way to home delivery of reliable birth control), our psychology is still tuned for an ancestral world. For ancestral men, hooking up was evolutionarily optimal in a way it was not for our prehistoric lady ancestors. (Guys only get pregnant from sex in creepy sci-fi movies.) The ancestral Adonis with all the notches in his spear handle would likely have left more surviving descendants to pass on his genes.

Sexual "economics" work like the monetary kind. An oversupply of women to men gives men the upper hand: transforming the mating "market" into one where men's evolved preferences rule. In short, women respond to the campus man famine (or more technically, the biased "sex ratio") "by offering sex without requiring high levels of commitment," explain evolutionary social psychologists Justin Moss and Jon Maner.

Assuming you continue to give hooking up the thumbs down, you might shop for potential partners off-campus (at events or via dating sites), where male-female ratios are less imbalanced. This should keep you from needing to make certain sacrifices to compete for men -- like offering really great sex and throwing in a kidney.

For pages and pages of "science-help" from me, buy my latest book, "Unf*ckology: A Field Guide to Living with Guts and Confidence." It lays out the PROCESS of transforming to live w/confidence.

I love my boyfriend. We've been together two years. Recently, however, we've been experiencing conflict over the issue of children. He wants kids; I don't. I've always felt strongly about this, and he said he was fine with this when we started dating. But he's been bringing up the subject of kids a lot lately (I suspect because he's thinking about popping the question). The discussions have grown fraught -- to the point where he was in tears at the end of an argument. I eventually said I could be open to kids because I love him and don't want to lose him. But can this be healthy for us long-term?

--Conflicted

Though many things in life come with the opportunity to push the "back" button, once you have a kid, you have a kid. You can't just drop 'em off at the fire station if they turn out to be precociously criminal -- already hot-wiring cars at age 7.

Deciding whether to have kids is a very recent state of affairs, coinciding with the development and availability of reliable birth control (starting in the late 1950s with the Lippes Loop IUD). For most of human history, unless a woman spent her fertile years all alone on one of those New Yorker cartoon desert islands, there was a good chance she'd have not just a child but the beginnings of a litter.

There's a widespread (and mistaken!) assumption that a woman who gives birth will immediately and unconditionally bond with her baby, explains anthropologist and primatologist Sarah Hrdy. Probably because of this, many people seem to believe the only thing stopping any woman from wanting a child is having yet to bring one into existence.

In fact, neither humans nor other mammals "automatically nurture each baby born," Hrdy observes. Clinical psychologist Idun Roseth and her colleagues, reviewing research on mother-infant bonding issues, report: "Most mothers find that feelings of affection come within a week from birth. However, some mothers are still struggling with this after many months. ... A small percentage may even have hostile feelings towards their infant."

In other words, the public has an overly rosy, sentimental -- and scientifically incorrect -- view of what's often referred to as the "maternal instinct." There is no such thing -- and the term "instinct" is the problem. The actual scientific definition of an instinct is an innate behavior ("factory-installed" -- present at birth rather than learned afterward) that members of a species perform automatically. An example is a baby's crying -- alerting everybody in earshot, "YO! I HAVE UNMET NEEDS!" (Nobody has to send their baby to crying school. It automatically wails its little head off when it's wet, scared, cold, or wants a sip o' nippy.)

In contrast with automatic instinctual behavior, there's behavior that's learned as well as behavior that is only sometimes triggered in some members of a species. Accordingly, the misnamed "maternal instinct" would be better termed a maternal impulse or motivation.

The impulse to nurture one's infant is just one motivation that may arise in a woman. Hrdy has long emphasized that ambivalence and even rejection of an infant are other impulses a new mother may feel. (Unfortunately, the myth of instantly falling in love with one's infant is so pervasive and strong that women who don't experience this tend to feel there's something wrong with them.) In reality, "maternal commitment" tends to emerge "piecemeal," Hrdy explains, and is "chronically sensitive to external cues."

By "external cues," she means a woman's current context -- such as whether she's unable to adequately feed and protect her infant. War, famine, postpartum depression, or even a new partner who doesn't want another man's child are contexts that may even trigger infanticide: a horrifying maternal impulse but a maternal impulse just the same. Thankfully, this impulse is relatively rare in our society, and many women (and men!) report "falling in love" with a child they never planned to have.

Maybe...possibly...you'd become one of those "in-love" women and be wildly happy you'd had children. However, in your email, you repeatedly made it clear that you don't want kids. You are only considering it because you love this man and don't want to lose him -- which is quite different from wanting children.

You might ask friends who are parents to an infant and other young kids to let you spend a long weekend with them. Admittedly, this isn't the same as parenting your own kids, but it might give you a sense of whether you're actually up for the job -- or whether you're like me. Personally, though I have great respect for devoted, loving parents, if I were in charge of a thing that screams like it's being eaten alive by a zombie, it would take about 20 minutes before there was grain alcohol in my coffee -- and in someone's sippy cup.

For pages and pages of "science-help" from me, buy my latest book, "Unf*ckology: A Field Guide to Living with Guts and Confidence." It lays out the PROCESS of transforming to live w/confidence.

I'm a woman in my 20s seeking a boyfriend. On the first date, I like to have a few drinks and, if the guy and I hit it off, have sex to see whether we have physical chemistry. Lately, I've had a string of great first dates -- flowing conversation, emotional rapport, and what seemed to be long-term potential -- yet they all ghosted me after sex. Are men still living in the Victorian Age?

--Confused

The wait to have sex with you mirrors the mandatory waiting period to buy a plastic squirt gun.

That said, you aren't wrong to want to figure out up front whether there's sexual chemistry. As for just how "up front" to do that, there's reason to slow your roll -- even if it means you get involved with a few guys who turn out to be sexual duds.

Because a woman can get pregnant from a single ill-advised naked romp, women evolved to be the "choosier" sex -- to take a "hmm, we'll see..." approach: stand back and assess a man's potential to "provide" and willingness to commit before dropping their panties (and everything else) on his bedroom floor.

Men co-evolved to expect female choosiness and to need to prove themselves over time to women of high mate value: women who can hold out for just the right guy. In short, men tend to value (and stick around for) what's hard to, uh, grope.

Women are also more likely to succumb to a sort of alcohol-induced blindness, which psychiatrist Andy Thomson, in an email to evolutionary psychologist David Buss, called the "Prosecco perception bias," after the Italian sparkling wine. Buss, who included this in his book, "When Men Behave Badly," explains that women have less of the alcohol-detoxifying enzyme, alcohol dehydrogenase. (That's why women get more rapidly drunk than men, even when they throw back less alcohol per pound of body weight.) "Because alcohol stimulates bonding endorphins, women are more likely to misread interactions with men" when tipsy, Buss explains, and "overestimate the likelihood of an emotional bond and a long-term relationship."

Sure, there are blissful long-term relationships that started out with no-strings-attached sex. However, because you're a woman hoping to find a boyfriend, having sex on the first date is a risky strategy. There's a way to get a guy to stick around after sex, and it's to wait to have it till he's got feelings for you -- though, admittedly, zip-tying him to your headboard works, too.

For pages and pages of "science-help" from me, buy my latest book, "Unf*ckology: A Field Guide to Living with Guts and Confidence." It lays out the PROCESS of transforming to live w/confidence.

I'm a straight guy using dating apps. What's with the constant flaking guy friends and I experience from women we're meeting for first dates? One woman on Hinge texted me to confirm 30 minutes before we were meeting at a bar but never showed and stopped responding to my texts. The next day, she complained that her phone had died. Another girl on Bumble agreed to have drinks, but when I texted her the day of, she unmatched. This extreme rudeness only happens with women I meet on dating apps, not those I meet in person, like at a friend's party. Any idea why?

--Disturbed

There are valid reasons to be a no-show for a date with no explanation, for example, the experience so many of us have of being abducted by aliens who don't have a charger that fits our phone.

This rudeness you're experiencing -- all these women treating you like a disposable object instead of a person with feelings -- isn't caused by app use, per se. The problem, as I explain in "Good Manners for Nice People Who Sometimes Say F*ck," is that we are now "living in societies too big for our brains": vast, transient "strangerhoods."

We didn't evolve to be around strangers and aren't psychologically equipped to live in a world filled with them because the psychology still powering our thinking (and behavior) today is adapted for small ancestral hunter-gatherer societies. Ancestral humans might've been stuck with pretty much the same 25 people for much of their lives (per estimates by anthropologists Robert L. Kelly and Irven DeVore) and might've have had a larger surrounding society of perhaps 100 to 150 people.

In the tiny ancestral world, the need to preserve one's reputation was a psychological police force that kept even rotten people from acting their rotten worst. (This is still a factor today in small towns where everybody knows everybody.) In contrast, strangers "meeting" in the virtual world -- on apps that are basically eBay for dates -- have no shared social context, so...bye-bye fear of reputational ruin!

In other words, when connecting via an app, it's probably a good idea to expect unreliability. You might even bring a book to read in case a woman ends up running a little late -- uh, intends to leave you sitting there at the bar until you decompose.

For pages and pages of "science-help" from me, buy my latest book, "Unf*ckology: A Field Guide to Living with Guts and Confidence." It lays out the PROCESS of transforming to live w/confidence.

I'm a divorced guy in my 40s. I was at a bar with friends and went over to talk with a woman I found really attractive. Though she wasn't the friendliest, I asked to take her to dinner. She said she'd think about it and then asked for my Instagram. Several days later, I texted her, and she agreed to go out. We've since had a few dates, but I'm bothered that she wouldn't go out with me until she'd scoured my social media. What does that suggest about her?

--Offended

You don't expect much from a woman who's "known" you all of 20 minutes: just blind trust that you'll do the gentleman thing of opening the passenger-side door for her -- as opposed to the psychopathic gentleman thing of stuffing her in your trunk.

Of course, the latter could happen if two gay men were dating, but there's good reason women -- more than men -- would opt for a "buyer beware" versus a "buyer be guessin'" approach. "Most men fear getting laughed at or humiliated by a romantic prospect while most women fear rape and death," observes personal security expert Gavin de Becker in "The Gift of Fear."

Even the stringbeaniest man can probably whup the average woman. Men have 15 to 20 times more testosterone than women, explain endocrinology researcher David J. Handelsman, M.D., and his colleagues. Higher "T" is associated with increased "muscle mass and strength" and "bone size and strength."

This means that even the power broads of the female athletic world are ill-prepared for any battle of the sexes. Take women's tennis rock stars Venus and Serena Williams. In 1998, when they were ranked fifth and 20th respectively, each got trounced by 203rd-ranked male tennis player Karsten Braasch -- whose "prep" for these matches was playing a round of golf and throwing back a couple of beers.

Beyond physical safety concerns, there's one half of the species that pees on little plastic sticks after sex to see whether they're about to make another human being -- one which, on average, will cost $233,610 to raise until age 17. (College, grad school, and multiple stints in rehab priced separately.)

This difference in male and female reproductive physiology led to the evolution of differences in male and female sexual psychology -- namely in their general level of sexual selectivity. It's in men's evolutionary interest to have sex with a slew of women -- and the hotter the better, because the features we find beautiful (youth, clear skin, and an hourglass figure) reflect health and fertility. (In a pinch, a woman with a pulse will do.)

An ancestral man could cut and run after sex -- leaving it to the Miss Neanderbrow he hooked up with to feed and care for any resulting fruit of the womb -- and still have a pretty good chance of passing on his genes. In contrast, ancestral women who didn't just stumble off to do it in the bushes with every Clooneyesque club toter likely left more surviving children to pass on their genes (carrying their psychology of choosiness).

Women's emotions push them to act in their evolutionary best interest. Women fear getting involved with men who will be unwilling and/or unable to pick up the tab if sex leads to, um, the creation of small mammals who will run up big bills at the orthodontist. In other words, it benefits a woman to scope a new man out and decide whether the ideal time to go to dinner with him might be the first Tuesday in never.

We're psychologically unprepared for the "evolutionarily novel" experience of vetting a stranger we meet in a bar, because our psychological operating system is adapted for an ancestral hunter-gatherer world: small, consistent communities of perhaps 25 to 100 people in which "intel" on a person was readily available through the grapevine. What's a modern, stranger-encountering woman to do? Well, this one apparently hoped to get some clues about you from your social media: probably from the sort of stuff you post, your follows and followers, and how you engage in the comments.

What does this woman's precautionary approach say about her? Well, probably that she isn't so desperate for a man or a free dinner that she'll take risks with her safety and go out with any Joe Bar Tab who offers to treat her to a meal. This isn't to say she's found a foolproof vetting method. Though social media is a new thing, it's rife with a well-worn evolved tool: deception -- used to defeat the precautionary strategies of the opposite sex. This typically leads not to rape or death but the sinking feeling of being had -- when, say, visits from the guy who posted pics of himself "flying private" always coincide with rolls of toilet paper going missing.

For pages and pages of "science-help" from me, buy my latest book, "Unf*ckology: A Field Guide to Living with Guts and Confidence." It lays out the PROCESS of transforming to live w/confidence.