Beyonce: do her hips make her attractive?

An hourglass figure has long been perceived to be the ideal figure for a woman to have.

But New York University researchers have found that to be found attractive, a woman had to move in a feminine way - swaying her hips.

Men, the Proceedings of the National Academy of Sciences paper found, were more attractive if they moved with a "shoulder swagger".

The waist-hip ratio has long been thought to be key to Western perceptions of attractiveness, with a small waist and bigger hips the ideal combination.

Marilyn Monroe, and now Beyonce and Jennifer Lopez are famous examples of women with that figure.

Its popularity may be down to media images, or because Western women do not need to have strong and muscular bodies in order to carry out manual labour, unlike women in developing countries.

But the US research, which was also published in the journal Psychological Science, suggests they would never have achieved their sex symbol status if they did not move in the right way.

Not just measurements

The team carried out a series of studies involving over 700 participants who were shown a variety of animations and videos of people moving.

Some showed shadow figures, where it was not possible to see if it was a man or a woman, while others obviously showed a man or a woman.

No matter which format was being used, the participants rated women or "female" figures as more attractive if their hips swayed as they walked, while men were more attractive if they had the characteristic shoulder movement.

The research also confirmed the waist-hip ratio assumption, with women's attractiveness being rated higher if their waist-hip ratio was small and men's being higher if their ratio was large.

The ideal waist-hip ratio for women is to have a waist measurement which is no more than 70% of their hip measurement.

But Kerri Johnson and Louis Tassinary who led the research, say their work shows attractiveness is not as simple as the difference between two measurements.

Writing in PNAS, the researchers said: "The body's shape and motion provoke basic social perceptions, biological sex and gender - ie masculinity or femininity respectively.

"The compatibility of these basic precepts predicts perceived attractiveness."

The team say their findings only apply to Western cultures, and other societies will judge attractiveness depending on their most prized feminine and masculine traits.

Dr George Fieldman, principal lecturer in psychology at Buckinghamshire Chilterns University College said: "This is quite plausible.

"It's the movement which attracts, and not just the waist-hip ratio per se."

He added: "It would be interesting to see what the ideal combination of measurements and wiggle is."