A study of how people respond to voices shows that men react far more strongly to a deeply pitched male voice than women do.

And humans, it seems, have the biggest sex-based differences in voice pitch of any primate. Women’s voices are far higher and men’s far lower, the team at Penn State University found.

“A lower pitch made men attractive to women. But it especially made men seem more dominant to other men,” said anthropologist David Puts at Penn State, who led the study team.

Puts studies gender-based differences and what they mean. In other primates, the differences between males and females tend to become more obvious when there’s a lot of competition for mates, he said.