The idea that little girls like everything in pink while little boys prefer blue appears to have a scientific basis according to a study showing that a person's colour preference depends largely on their s*x. Scientists have found that women tend to prefer pink - or at least a redder shade - while men prefer blue, and that the gender difference may be down to genes rather than upbringing. The study investigated the long-held - but until now largely unsupported - view that women and men differ in their colour preferences. It is the first to show that there is a scientific basis for the idea that girls are born with a particular affinity for pink colours. The researchers, Anya Hurlbert and Yazhu Ling of Newcastle University, said that despite the evidence for differences between the s*xes in terms of visual skills, there was no conclusive proof of s*x differences in colour preference.This fact is perhaps surprising given the prevalence and longevity of the notion that little girls differ from boys in preferring pink, they say in the academic journal Current Biology. Dr Hurlbert recruited 208 people aged between 20 and 26 for the study and subjected them to a battery of tests to determine their colour preferences. A substantial minority - 37 - of the group were born and raised in China, which allowed the scientists to compare the preferences of people from two different cultures. As fast as they could, each young man and woman had to choose their preferred colour from a series of paired, coloured rectangles shown on a computer screen. The universally preferred colour for both s*xes was blue, but females also showed a distinct preference for reddish colours, Dr Hurlbert said. Although we expected to find s*x differences, we were surprised at how robust they were, given the simplicity of the test, Dr Hurlbert said. On top of the universal preference for blue, females have a preference for the red end of the red-green axis, and this shifts their colour preference slightly away from blue towards red, which tends to make pinks and lilacs the most preferred colours in comparison with others. When the two scientists compared the colour preferences of the white British parti nts with the men and women brought up in China, the same s*x differences emerged, with Chinese females again showing a clear preference for pink. This suggests that, whatever is the underlying explanation for the differences in colour preferences between men and women, it seems to be biological rather than cultural, Dr Hurlbert said. Human vision is trichromatic, meaning that we have three colour-sensitive pigments in our eyes - like chimps, gorillas and other apes. Biologists believe trichromatic vision in primates came about as a result of the need to distinguish ripened fruit, as well as young, nutritious leaves, in a forest canopy. However, early human societies almost certainly engaged in a division of labour between the s*xes, with men travelling long distances to hunt wild game. Women, meanwhile, foraged locally for fruit and berries. Dr Hurlbert suggests that this division of labour may be at the root of why girls now prefer pink. Evolution may have driven females to prefer reddish colours - reddish fruits, healthy, reddish faces. Culture may exploit and compound this natural female preference, she said. As for the wider human preference for blue, Dr Hurlbert said this may have something to do with our love for the grassy plains of our place of origin, in Africa, where the sky is an important feature of the landscape. I would favour evolutionary arguments here, she said. Going back to our 'savannah' days, we would have a natural preference for a blue sky, because it signalled good weather.