Ah, the mystery of attraction. Ever wonder what she sees in him? Or what he sees in him?

We’ve all spent three months or so with someone only to turn around after the initial chemical buzz wears off and go, “What the hell was I thinking?” And many have found themselves falling for those they initially considered unattractive or at least unlikely partners. That last is because research shows the charms of your personality can change others’ perception of your physical attributes.

Science has been trying to figure out for ages why we want to date, marry or just do the horizontal mambo with certain people and not others. And future research from the frontiers will tell us how laws of attraction work for those who are gender-fluid.

Let’s just say being familiar with the unconscious triggers of our own behaviour is a good mental health indicator.

What the experts say

“We showed male participants pictures of females either bordered in red or in other colours, or with a red shirt or other coloured shirts. Guys who saw females in red wanted to date them more. One explanation is that it’s a learned phenomenon, that red is the colour of Valentine’s Day hearts and lipstick and takes on in our culture a connotation of sex and romance. The other is that it’s deeply ingrained and might be biologically based, as when male primates in the wild see females’ hindquarters turn red, a sexual cue that they’re in heat. My guess is that it’s a combination of both.”

ANDREW ELLIOT, professor of psychology, U of Rochester, New York

“We used computer animations to manipulate two body cues. One was body shape – how curvaceous the body is – and the other how the body walked. There were no facial characteristics. There was no clothing. We showed these to research participants and asked three questions: sex categorization, how masculine or feminine is the target, and how attractive is this target? Bodies perceived to be men were more attractive when perceived to be masculine, and bodies perceived to be women were more attractive when perceived to be feminine. We got the same pattern regardless of the perceiver’s sex. In a separate study using non-visual cues, the same basic pattern emerged when gay men and lesbian women made judgments about prospective dating partners.”

KERRI L. JOHNSON, professor of communications studies and psychology, UCLA, Los Angeles

“Each individual has a unique odour print determined by the set of genes that regulate the immune system. Those roughly 55 genes are so variable that no two individuals will have the same genotype in those genes, so no two individuals will have the same odour print. In studies, people can smell differences in this odour print and will report that they’d like to socialize with individuals whose underlying genotype is different from their own. There are now pheromone parties. People wear T-shirts for extended periods; then they get together and smell the T-shirts and [choose who they will date].”

CHARLES WYSOCKI, behavioural neuroscientist, Monell Chemical Senses Center, Philadelphia

“If you have people of average attractiveness and you find out good things about them – they’re smart, funny, kind, caring – you will come to see their physical qualities differently and see them as more attractive. To a matter of degree, of course. People can be perceived as attractive, but if you learn negative things about them, they become uglier. It shows it pays to be a good person and people will find you more physically attractive based on the quality of your personality.”

GARY W. LEWANDOWSKI JR., professor of psychology, Monmouth University, West Long Branch, New Jersey

“In the speed dating data set we looked at, we found that the best predictor of who people were interested in dating was their physical appearance – perhaps not surprisingly. Since it’s true that physical attraction can change over time, I think this suggests that it’s at least possible that people are eliminating from consideration people whom, if they got to know them in a different way, they might find to be compatible mates. It’s difficult to sustain a successful romantic relationship with someone to whom one is not physically attracted, but again, it’s probably true that perception changes over time, so maybe it’s not quite as big a barrier as one might have thought.”

ROB KURZBAN, professor of psychology, U of Pennsylvania, Philadelphia