Scientists at the University of Western Australia have published research that suggests men can successfully judge a woman's character simply by looking at one small photograph of her face.
Participants in the study, led by Dr Samantha Leivers, were given 17 cards, each with two photographs of separate women on them - matched for age and ethnicity. One of these women was of unshakeable fidelity, and the other had, in the past, been caught cheating on her partner.
After being asked to identify the heartbreakers on each card, researchers found the majority of participants guessed correctly, with nothing to go on other than the features in the photographs.
Between 55 and 59 per cent of men guessed correctly every time, a small difference described by Leivers as "statistically significant but modest".
"We don't expect them to be 100 per cent accurate when they are literally just looking at someone's face for a few seconds," she said. "But the fact that they're showing any accuracy from this limited information at all is pretty cool."
The researchers believe that the way people hold their faces may be accurate indicators of emotional and empathetic ability.
"For example," reads the study, "emotion expression has been found to influence a number of trait judgments including perceived trustworthiness." So despite showing neutral expressions, perhaps the subtle differences in the female subjects' facial expressions betrayed their true natures.
Leivers and her team plan further research into a link between expressions and emotions.