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.