How a chap can spot a serial love cheat just by looking at her face

THEY say you should never judge a book by its cover.

But men might be able to tell how faithful a woman is just by looking at her face, researchers have discovered.

Men who were asked to study photographs of 34 women were able to identify which of them had previously cheated on their partners 59 per cent of the time.

The researchers asked the men to look briefly at the women’s photographs, but gave them no additional information about them. The photos were shown in pairs – where one of the women had cheated on a partner at least twice, and one had always been faithful. When asked to choose the more faithful woman, the men ‘ performed significantly above chance’, the study found.

The experiment was repeated with another sample of men, yielding similar findings.

In the first test, the men successfully chose the faithful woman 55 per cent of the time. This averaged out at a 59 per cent success rate over the two experiments.

Previous research has suggested that attractiveness can act as a cue for how faithful a women is perceived to be, but this study found no link between the men’s judg- ments and those women rated as more attractive. It was not clear, therefore, why the men rated faces in a particular way, and further research is needed into what cues men look for when assessing how trustworthy a potential partner is.

But the scientists said that, from an evolutionary perspective, it makes sense that men would have developed the ability to spot a cheater because men can never be sure a child is genetically theirs.

This means they could spend all their time and energy raising a child that is not theirs – and would therefore not pass on their genes – if their mate became pregnant by another male, they explained. Publishing their findings in the journal PLOS One, the experts wrote that, because of the ‘significant cost associated with cuckoldry’, men would probably have ‘evolved the ability to predict or detect unfaithfulness in a potential partner’. They went on: ‘We show for the first time that men’s judgments of faithfulness from images of women can contain a kernel of truth when they are able to directly compare images.’

The team, from the University of Western Australia, added: ‘Previously, accuracy in faithfulness judgments has only been found for women judging men’s faces.

‘It is striking that men were able to show any accuracy from images alone after only a brief presentation.’ A study last year found we tend to judge someone with high eyebrows and prominent cheekbones to be more honest.

The psychologists from New York University also found that the brain decides a person’s trustworthiness before we have even consciously perceived who they are.

The brain takes just 33 milliseconds – a tenth of the time it takes to blink – to decide whether someone can be trusted.

‘Significant cost

of cuckoldry’