A small waist and big hips suggest a woman is smarter and more fertile

There could be a scientific reasons why people can't stop talking about Kim Kardashian’s curvaceous backside.

Evolutionary scientists claim the male attraction to a large female bottom is due to an ingrained preference for women with a small 'waist to hip ratio,' the Daily Mail reports.

The waist-hip ratio is calculated by dividing the waist measurement by the hip size. The smaller the waist in relation to the hip, the more attractive a woman appears to a man.

Previous research has found women with small waists and big hips have higher levels of fertility.

New Zealand anthropologist, Barnaby Dixson, set out to find what makes a woman attractive to men.

A group of volunteers were presented with various pictures of a woman in which her bust, waist and hips had been digitally altered, and they were asked to rate the image for attractiveness.

Infra-red cameras tracked their eyes as they looked at the photos. Although most were initially drawn to the woman's cleavage, hips and waist were key to attraction.

A separate study of 16,000 women by the Universities of Pittsburgh and California in 2007 found that curves are linked with intelligence.

They discovered that women with a greater difference between the waist and hips scored much higher on the tests, as did their children.

The study concluded that fat around curvy hips and thighs holds higher levels of omega-3 fatty acids, which are essential for the growth of the brain during pregnancy.

The fat which collects around the waist, however, is more likely to contain omega-6 fatty acids, which is less suited to brain growth.

Reporting in the journal Evolution and Human Behaviour, the researchers found that the children of curvy mothers are more likely to do well in cognitive tests than others.

As well as boosting brainpower, omega-3 fatty acids found in oily fish are considered to be of huge health benefit.

They have been found to stave off cancer, keep blood pressure down, slash the risk of heart attack, ward off Alzheimer's and protect against mental health problems.