Coty perfume ads had it wrong. Whispering is not the ideal mating signal. Pushing your voice up the scale a click is better. While the low, whiskey voice holds a reputation for sultriness, the female voice actually rises during the most fertile days of her cycle.
This goes back to the larger subject of “female mate choice.” Everything does, really.
Females throughout the natural world are tasked with finding the perfect match for their DNA, while fending off a barrage of males who are often bigger and stronger. What’s a girl to do?
The human female hit on an ingenious innovation: Cryptic ovulation. Unlike some of her primate sisters, the human female does not advertise her fertile days with a balloon of red skin that inflates on her behind. We keep it hidden. It increases our ability to choose the father of our offspring.
With males unable to determine if we’re fertile, they’re forced to either mate-guard us 24/7, or do their best to earn our loyalty.
But we leak cues. And one of them is our tone of voice. In the current paper, researchers recorded women’s speech over the course of their cycle. Sure ‘nuf, the larynx seems to tighten a skidge as peak fertility approaches, presumably as a rising tide of estrogen reaches hormone receptors on the vocal cords.
What’s more, men who listened to the recordings rated those higher voices as more attractive. Clever men! Maybe ovulation isn’t so cryptic after all.
The message to females who wish to conceal their fertility status, the message is clear: If you don’t want someone’s attention, keep your mouth shut.
