Last Manchild Standing

I'm dating a new guy. When we're alone, he's sweet and a complete gentleman. However, whenever we're around his guy friends, he comments about how attractive he finds other women, rants about sports, and farts in front of me. I've hinted that this makes me unhappy, but nothing changes.

--Upset

Love can be transformative -- turning men into emotional marshmallows -- which can lead a 20-something lovestruck dudebro to want to make it known to his posse: "I will not be waking up on Tuesday all Harry Styles in a dress on the cover of Vogue." Your boyfriend's loutish behavior -- talking about other girls and farting in front of you -- sounds like a "costly signal," a form of advertising used by both animals and humans. A costly signal is a trait or behavior that's so wasteful, extravagant, and threatening to one's evolutionary interests (mating and survival) that it's likely to be a truthful indicator of an organism's financial, social, or physical mojo. The peacock's tail is an example. As evolutionary psychologist Steve Stewart-Williams points out in "The Ape that Understood the Universe," it's like "a giant billboard": a huge electric blue and green yoohoo! to peacock-eating predators. This big bunch of buttfeathers also seriously slows the peacock's escape. However, the larger and more lush a Mr. Peacock's tail, the more the peahens (the lady peacocks) go for him. (The fact that he avoids becoming lunch while lugging around this massive feathery impediment suggests he must be a particularly buff and genetically superior example of peacockhood.) Chances are your boyfriend is rude-vertising to the guys: Sure, he has love in his life, but he hasn't gone all bought, sold, and girlfriend-controlled. The costly signal in this? He's so secure in his sexual magnetism (like, the hot chicks are lined up and begging) that he can afford to act like a turd to his girlfriend. Um, no. Or at least, that's what you need to put out there. In words, not hints. Tell him it's humiliating when he comments on other women when you're right there, plus the farting thing is a sexual turnoff. In short, he's transforming you into an unhappy girlfriend who won't want to have sex. Assuming he cares about you, you should see an abrupt end to the show he's been putting on for his dudebros: "No, I Haven't Become A Love Muppet Colonized By The Enemy." ... 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.