London: Ladies, you do have to kiss a lot of frogs before you find your prince!
Kissing helps us size up potential partners and, once in a relationship, may be a way of getting a partner to stick around, a new Oxford study suggests.
"Kissing in human sexual relationships is incredibly prevalent in various forms across just about every society and culture," said Rafael Wlodarski, from the Department of Experimental Psychology at Oxford University.
Wlodarski and colleagues set up an on-line questionnaire in which over 900 adults answered questions about the importance of kissing in both short-term and long-term relationships.
"There are three main theories about the role that kissing plays in sexual relationships: that it somehow helps assess the genetic quality of potential mates; that it is used to increase arousal; and that it is useful in keeping relationships together. We wanted to see which of these theories held up under closer scrutiny," Wlodarski said.
The survey responses showed that women rated kissing as generally more important in relationships than men.
Furthermore, men and women who rated themselves as being attractive, or who tended to have more short-term relationships and casual encounters, also rated kissing as being more important.
Previous studies have shown women tend to be more selective when initially choosing a partner.
Men and women who are more attractive, or have more casual partners, have also been found to be more selective in choosing potential mates.
As it is these groups which tended to value kissing more in their survey responses, it suggests that kissing helps in assessing potential mates, researchers said.
It has been suggested previously that kissing may allow people to subconsciously assess a potential partner through taste or smell, picking up on biological cues for compatibility, genetic fitness or general health.
"Mate choice and courtship in humans is complex," said Professor Robin Dunbar.
"Initial attraction may include facial, body and social cues. Then assessments become more and more intimate as we go deeper into the courtship stages, and this is where kissing comes in," he said.
In the current study, the team found that kissing's importance changed for people according to whether it was being done in long-term or short-term relationships.
Particularly, it was rated by women as more important in long-term relationships, suggesting that kissing also plays an important role in mediating affection and attachment among established couples.
The researchers report their findings in the journals Archives of Sexual Behaviour and Human Nature.