Women can tell whether a man likes children simply by looking at his picture, and they are more attracted to the ones who do when they are looking for a long-term relationship, research suggests.

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 men who look like the actors Tom Hanks or Leonardo di Caprio are more likely to be judged as being interested in children, as their faces are themselves more child-like.

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 more masculine features, such as a heavyset jaw, smaller eyes and a strong bone structure, which tend to convey high testosterone levels and a more aggressive and 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 a man's genetic quality and masculinity should be more important.

In the study, which was published yesterday 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. Saliva samples were also tested for testosterone levels.

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

The women were asked to judge which men were most interested in children, which were 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.

(China Daily 05/11/2006 page6)