The story was tailored perfectly for the day: On the eve of the calendar's most romance-oriented holiday, a panel of philematologists at the AAAS Annual Meeting in Chicago gathered to explore cortisol, oxytocin, the hot flashes of an fMRI, and, of course, estrogen and testosterone.

After an hour-long pre-Valentine's Day press briefing on the science of kissing, many reporters came away with a vision of kissing as a snapshot of evolution in action.

"Researchers believe that the touching of lips is a 'biological' quality-control strategy for 'mate assessment' which has evolved over millions of years, wrote Richard Alleyne, science correspondent for the U.K.-based Telegraph. "It also triggers certain hormones that reduce stress, increase attachment between a couple and increases the sex drive."

Randolph E. Schmid, writing for the Associated Press, approached it through the lens of pop culture. His story, picked up in the Minneapolis Star-Tribune and many other publications, begins:

"'Chemistry look what you've done to me,' Donna Summer crooned in Science of Love, and so, it seems, she was right. Just in time for Valentine's Day, a panel of scientists examined the mystery of what happens when hearts throb and lips lock. Kissing, it turns out, unleashes chemicals that ease stress hormones in both sexes and encourage bonding in men, though not so much in women."
 
Katherine Hobson, after talking with several of the speakers slated for a AAAS symposium on Valentine's Day, came away with a similar view.
          
"A kiss, as we're now learning from scientific research, is hardly just a kiss," she wrote in a story posted on the U.S. News & World Report website. "Rather, it's a complex act of courtship that may help us pick our mate, perhaps even through unconscious chemical signals, and assess and maintain a relationship."

Fiona Macrae, writing the Daily Mail, took more of a get-down-to-brass tacks approach.

"A first kiss is not only hotly anticipated," she wrote. "It could help a girl tell a frog from a prince."

There are two sides to that story, of course. Citing researcher Helen Fisher of Rutgers University, Macrae wrote that "studies suggested men use kissing to gauge levels of the sex hormone estrogen in a woman's saliva."

Which may explain, Fisher said, why "men like sloppier kisses."

Where will this research lead in the future?

"I think that is just the beginning of what we are going to find out," Fisher says in the Daily Mail. "We are going to find many other mechanisms we unconsciously use to size up a person's biological traits.

"There are all sorts of things that we advertise that we don't even know about."

Another thing we might not know about: philematologists. They are scientists who study  kissing.

The science of kissing will be the subject of a symposium at the AAAS Annual Meeting from 8:30 to 11:30 a.m. on Valentine's Day. The symposium was organized by Albert H. Teich, head of Science and Policy Programs at AAAS, and his spouse, Jill Pace, of the American College of Real Estate Lawyers.