Scientists in the United States have found that women are surprisingly accurate at guessing male affinity for infants from facial cues alone, and use these to help to select a suitable mate with whom to start a family.

When women want a short-term relationship, however, they favour male faces that are strongly masculine, which tend to belong to men with higher levels of testosterone, the study indicates.

Dario Maestripieri, of the University of Chicago, who led the research, said that men who looked like the actors Tom Hanks or Leonardo di Caprio were more likely to be judged as being interested in children, as their faces were themselves more child-like.

“They have more rounded features, smaller chins, friendly expressions, and eyes that are relatively large compared to the size of their heads,” he said. “Women take a look at someone like Tom Hanks and come away with the impression that he’s friendly and warm towards children.”

These rules of attraction, however, are far from infallible. Although Tom Hanks has four children, he left the mother of his first two.

This contrasts with men who have more masculine features, such as a heavy-set jaw, smaller eyes and a strong bone structure, which tend to convey high testosterone levels and a more aggressive, less caring personality. Examples include Mickey Rourke and Christopher Reeve, Dr Maestripieri said.

While these qualities might be appealing for a brief liaison, they are much less attractive in a long-term mate. The findings fit with evolutionary predictions of how female mate preferences should differ in response to particular circumstances.

When considering a long-term partner who will help to bring up children, evolutionary theory suggests that women should favour men who show a willingness to invest in their offspring. For a short encounter, however, a man’s genetic quality and masculinity should be more important.

Dr Maestripieri said that this had been borne out by the research. “The study provides the first direct evidence that women’s attractiveness judgments specifically track both men’s affinity for children and men’s hormone concentrations,” he said.

In the study, which is published today in the journal Proceedings of the Royal Society, 39 men were shown a series of pairs of pictures, one showing an adult and one a baby.

The subjects, who were aged between 18 and 33 and heterosexual, were asked to select which image they found more interesting.

Some men chose only the baby pictures, some only the adult pictures, and some a mixture of the two. Saliva samples were also tested for testosterone levels.

The men were then photographed with a neutral expression, and the pictures were shown to 29 heterosexual female volunteers.

The women were asked to judge which men were most interested in children, which were the most masculine, and which they found attractive for long and short-term relationships.

The women picked the men who were most interested in children with remarkable accuracy, and also chose as more masculine the men with the highest testosterone levels. The men who were interested in children were judged as more appropriate long-term partners, while more masculine ones were preferred for short-term relationships.

The pictures that were used in the research were not published because of confidentiality agreements with the participants.

THE WOMAN’S VERDICT ON MEN’S FACES

Tom Hanks
He’s a great example of a man that women would see as interested in children. He has rounded, child-like features, a small chin and a friendly expression

David Tennant
His face strikes me as unremark-able either way. He has a friendly, nice expression, but it’s not easy to classify into either category

Daniel Craig
He’s a good example of a more masculine type of face. He is tough looking, with a strong jaw-line and strong bones. The eyes are also smaller in relation to the head

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