The facial proportions of the average hot guy haven't changed much throughout human evolutionary history, finds a new study that compares contemporary human skulls with skulls from 2.6 million years ago. Women have been selecting for males with short, broad faces—think Brad Pitt and Will Smith—since the dawn of man, and chimps do the same.
Facial symmetry and masculinity have been found to play a central role in the rules of attraction, but proportionality is a first, LiveScience reports. "We have found that the distance between the lip and brow was probably immensely important to what made us attractive in the past," said the leading researcher. But the scientists are still trying to figure out why.