Women's fear of spiders has now been linked to the behavioural traits of our hunter-gatherer ancestors
A new study in the US suggests that women have a genetic aversion to dangerous animals, such as spiders.
The research, published in the New Scientist, says women are born with character traits that were ingrained in our hunter-gatherer ancestors.
As child protectors, they have to shun animals that threaten them or their young off-spring, researchers said.
Previous research suggested women were actually up to four times more likely to be afraid of creatures like spiders.
The new research was headed up by developmental psychologist, Dr David Rakison, from Carnegie Mellon University in Pittsburgh, 10 baby girls, and 10 baby boys were subjected to a number of pictures of spiders to gauge their reactions.
First the babies were shown a picture of a spider with a fearful human face, followed by images of a spider paired with a happy face - alongside an image of a flower twinned with a fearful face.
The results showed that the girls - some as young as 11 months old - looked longer at the picture of the happy face with a spider than the boys, who looked at both images for an equal time.
The researchers concluded that the young girls were confused as to why someone would be happy to be twinned with a spider, and were quick to associate pictures of arachnids with fear.
The boys, it seems, remained totally indifferent emotionally.
Mr Rakison attributes this genetic predisposition to behavioural traits inherent in our hunter-gatherer ancestors.
Men, he purports, were the greater natural risk takers, the ones who took greater risks were more successful when going out to hunt for food.
With women, in their role as natural child protectors, it made sense for them to be more cautious of animals such as snakes or spiders, Mr Rakison adds.
By contrast, the research concludes that modern phobias such as the fear of hospitals - or that of flying - show no differences between the sexes.
Previous research has shown that almost 6% of people have a phobia of snakes, with nearly 4% scared of spiders.
However, of that percentage, four times are likely to be women than men.
This page is best viewed in an up-to-date web browser with style sheets (CSS) enabled. While you will be able to view the content of this page in your current browser, you will not be able to get the full visual experience. Please consider upgrading your browser software or enabling style sheets (CSS) if you are able to do so.