A group of macaques groom each other. Could this be where women got their warm greeting rituals? (Richard Kirby/Nat Geo Wild)

I first started paying attention to the ways my female friends and I greet each other over the summer.

I met up with an old friend whom I hadn’t seen in weeks, and our exchange went something like this:

“Look at you! You look adorable. It must be the hair,” I exclaimed.

“Are you kidding me, I’m hideous,” she said. “I ran out of products, and I couldn’t get my curls to spiral. You look terrific! I love that dress.”

“No, don’t look!” I insisted. “It’s so shapeless, but I figured we’d be okay for just sitting around the pool.”

Maybe because it was just the two of us in the elevator, maybe because we were so over the top, but we both noticed our greeting ritual was all about compliments — the need to give them and the reflexive need to reject them.

This was our preamble. Before we could talk about her career, her plans to move across the country, my kids or any of the presidential candidates, we spent long minutes on “Your eyebrows are always so spectacular!” — things that simply had to be said.

After that, I started noticing that I did the same thing with all my close friends, my not-so-close friends, my colleagues and the woman who changes the toilet paper in the bathroom at the office. “I love the way your eyeglasses frame your face. And that color? Cute. On. You.”

The other day, after a full-out paroxysm of greeting-gush at work, I asked other women about the strange ritual of female hellos. One called it a “verbal version of grooming” each other the way primates do in the wild. She worried about the unintended damage all the compliments might be doing to her daughter, and it reminded me of a recent Washington Post column on best practices for complimenting girls. Others talked about having to fight their tendency to be self-deprecating.

I talked to Elaine Showalter, a Princeton professor emeritus of English and humanities, who called it a sincere, modern feminine behavior.

“Thinking about literary examples, until the 20th century, it wasn’t good form to comment on other people’s appearance,” Showalter said. “It’s not the way heroines greet each other in novels.” She called it a bonding between women: “affectionate and sisterly.”

The other day, she had passed a stranger in a nice outfit in the veggie aisle at her grocery. “I just have to tell you, you look so sharp today, you win the fashion prize at Wegmans,” Showalter blurted.

“I will say that to another woman with no intention other than for her to have a nice day. To make a connection,” she told me. “When I hear it, it makes me feel good.”

And, she says, it’s one behavior that transcends class and race and generations. “It feels very comfortable to say to somebody you absolutely don’t know, and in ordinary social worlds you have absolutely nothing in common with, who is 30 years younger, in a completely different line of work . . . ‘My God! That hair is amazing!’ ”

Doesn’t quite work the same for men.

When my then-fiance was looking for wedding suits over the summer, I reminded him that my brother-in-law is a spiffy dresser. Lay everything out, take pictures, then send them to Darryl and see what he says, I suggested.

Good idea, yes?

No response.

“You’re not going to do it, are you?”

“Not at all,” he said.

Male communications are about status, and female communications are about connection, says Deborah Tannen, a linguistics professor at Georgetown and a best-selling author who specializes in communication rituals. “If you don’t recognize a ritual as a ritual, you take it literally and you don’t give it the right response,” she said in a video lecture on YouTube.

As children, “boys are trying to top each other” and negotiate for higher status, while “girls try to show they’re the same” and use language to create friendship.

Her words made me appreciate the ways women say to one another that we’re all in the same place, trying to fit in, struggling together. I want to thank Tannen for her explanation. Of course, I’ll have to start by telling her how very stylish she looked in the video.

For more by O’Neal, visit wapo.st/lonnae.