Prof van Vugt said: “Men definitely have the most wandering eye but it is because they have evolved to pay attention to cues of fertility and one of those cues is facial beauty – it’s not that men are shallow.

“But we found they do make snap judgments about women, much earlier than was previously thought. They make that decision on whether a woman would be a good mating partner in milliseconds.

“This is something very ancient and a way of helping men find the best mate to produce children.

“Women were not distracted by attractive male faces because women need more proof of whether a man is a good mate.