A kiss on a first date is for many the barometer for its general success.

However, new research suggests that the purveyor of the first date lip-lock may be expressing more than the feeling that they've enjoyed dating you.

According to psychologists at Albright College in Pennsylvania, there are hidden, perhaps even unconscious motives for a post-dinner pout when it comes to dating.

A feeling in the genes

Yes, that is genes, not jeans. Researchers studying more than 1,000 college students, chemicals and sensory information delivered in a kiss are used by dating couples to assess the potential for future relationship success.

Susan Hughes, assistant professor of psychology at Albright College, points out that there is a lot more science to a kiss than participants realise.

She told Canada.com: "We use smell, taste and pheromones to select a mate who'll be most likely to stick around afterwards and help raise the child.

"Of course, this is all happening on a subconscious level. We know great chemistry when we feel it, but we're not identifying what makes it such a good kiss."

But the study also found that the dating kiss signals gleaned by women differ from those that men are searching for. According to the Ms Hughes, males are in fact less concerned about where their dating antics may lead in the future, and are interested in finding out their chances of getting their date into bed.

"Females place more importance on kissing to screen for potential mates, while men, especially with short-term partners, use kissing to increase their chances of having sex," she notes.

The treachery of the tongue tussle

However, the dating kiss does not always run as smoothly as many hope, with a bad kiss the downfall of many successful dates.

Wouldn't life be so much simpler for those that are continually unlucky in love if they found out that all that is needed is a little change in their kissing technique, rather than abandoning the dating cause altogether?

Fortunately for them, CNN has compiled a list of the worst meetings-of-mouths ever to have found their way into the world of dating.

Among the most ill-advised oral misadventures is the Venus Flytrap, through which the protagonist opens their mouth so wide during a kiss that it restricts the recipients ability to breathe.

Dating couples may stand themselves in better stead if they concentrate as much on what their own kissing technique tells their partner as anything else.