The study aimed to understand why humans, and not animals, frequently kiss each other. It was a survey of 900 people, who were asked to rate the importance of kissing in the early stages of a relationship, before, during and after sex.
Results indicated that women, and not men, rated kissing as more important, suggesting that kissing could perhaps be viewed as a sort of compatibility test.
"People are extremely good at assessing where they are in the "mating market" and pitch their demands accordingly. It depends what kind of poker hand you've been dealt. If you have a strong bidding hand, you can afford to be much more demanding and choosy when it comes to prospective mates," said Prof Robin Dunbar of Oxford University, one of the authors of the study.
The study details appear in the Archives of Sexual Behavior.