According to scientists, facial expressions can give a clue to the sort of relationship people are seeking.
Researchers from the universities of Durham, Aberdeen and St Andrews conducted a survey of 700 heterosexuals in their early 20s, asking them to judge the attractiveness and attitudes of people from photographs shown to them.
Heterosexual participants were shown pairs of photographs of men and women in their early 20s. They were asked to choose the face they felt would opt for short-term sexual relationships, one-night stands and sex without love.
This choice was compared with the real-life sexual behavior and feelings of the people in the photographs that were shown in a detailed questionnaire.
The participants were also asked which face they thought was the most attractive for a long or short-term relationship, which faces held masculine and feminine appeal and which of the faces mirrored the committed types.
According to the research findings published in the journal of Evolution and Human Behavior, in one study of 153 participants, 72 per cent of those who took part, correctly identified the attitudes of people from photographs.
The study found that people relate physical features to sexual character.
The findings also disclosed that women seeking a long-term relationship prefer men with softer features, which suggest they will want to settle down. Men with facial features like Johnny Depp, the Hollywood actor, for instance.
Women will avoid men with strong jaws and small eyes that they perceive as less committed to raising a family—George Clooney the actor, for instance.
Women's ability to pick out the masculine types who only wanted casual sex is thought to help them decide which man should be to the one to father their children.
The study suggests that men are drawn to women with large lips and open eyes, similar to the likes of actress Angelina Jolie.
Men saw those women with the most attractive features, the most likely to be willing to have casual sex.
Lynda Boothroyd, of Durham University and the lead author of the study, said, "Preferences for different types of face were actually quite strong." She added, "This shows that these initial impressions may be part of how we assess potential mates — or potential rivals — when we first meet them."
Dr Ben Jones, of the University of Aberdeen's Face Research Lab, said, "Lots of previous studies have shown that people can judge a lot about a person from their face, including things like health and even some personality traits like introversion."
"But this really is the first study to show that people are also sensitive to subtle facial signals about the type of romantic relationships that others might enjoy," he added.