Fancy butch men? Then you probably live in the city: Urban life makes us more attracted to masculine males and feminine women.

In a world of supermodels and Hollywood heart throbs, it’s easy to assume many of us want our men to be manly and our women girlish and womanly.

But new research suggests that, rather than being a sexual selection preference that has evolved over hundreds of years, it’s a relatively new habit that has only emerged in modern, urbanised societies.

A team of psychologists found that people in small-scale, more rural societies instead have a preference for more netural, or least ‘sex-typical’ features.

The researchers, which also included anthropologists and biologists led by Brunel University London, surveyed 12 populations around the world, from the primitive to the highly developed.

Surprisingly, only in the most industrialised and urbanised environments did people hold the well-worn opinion that highly feminine women, and highly masculine men are attractive.

Lecturer in psychology at Brunel University London, Andrew Clark, said: ‘We digitally morphed masculine and feminine faces from photographs of people to find out what choices people from small-scale societies made.

‘We found that they didn’t place the same emphasis on ‘sex typicality’, that is, on highly feminine women and highly masculine men.

In fact, they often favoured the neutral face, and sometimes the least ‘sex-typical’ one.’

The team also found that the perception that masculine males appear aggressive increased with urbanisation.

A total of 962 participants were shown sets of three opposite-sex composite, and digitally-manipulated photos.

For each set of photographs, representing different ethnic groups, participants were asked which face was most attractive and which appeared most aggressive.

‘This data challenges the theory that exaggerated sex-specific traits were important for social and sexual selection in ancestral environments,’ added Dr Clark.

‘Preferences for sex typical faces are a novel phenomenon of modern environments. It’s probably not a consistent thread in human history.’

The team suggest that highly developed environments with large, dense populations may have exposed individuals to a greater range of unfamiliar faces, providing the opportunity – and perhaps motive – to discover subtle relationships between facial traits and behaviour.

The findings are published in the journal PNAS.