A new study reveals that men and women are attracted to partners with facial characteristics similar to their opposite-sex parent. The study provides evidence that evolutionary drive partly determines physical attraction.

A team of researchers, led by Tamas Bereczkei at the University of Pécs in Hungary, evaluated 312 Hungarian adults from 52 different families. Each family included a couple and both sets of parents. Researchers measured ratios of 14 different facial zones including the width of jaw and the distance between mouth and brow.

The data indicated that women were drawn to male partners with similar facial ratios to their fathers, while men were drawn to partners whose lower facial features were similar to their mothers’. “Freud may be right in that a strong emotional relationship between mother and son have a strong effect on later life,” said Bereczkei.

Another study offers evidence that people gravitate toward partners with similar facial characteristics to their own. According to Liliana Alvarez and Klaus Jaffe at the Universidad Simón Bolivar, such resemblances often mean that people find partners who look like family members.

But the Hungarian study suggests that familiarity is not the only key to attraction, as male participants did not seek out female partners who resembled their fathers and female participants did not seek out male partners who resembled their mothers. Researchers suggest that choosing mates who represent one parent and not the other may be a way of preventing inbreeding, (which can have negative genetic consequences) while preserving family genes.