About the SA Blog Network

Bering in Mind

Bering in Mind

A research psychologist's curious look at human behavior
Bering in Mind Home

Voices Carry (Signals of Your Sexual Intent and Reproductive Value)

The views expressed are those of the author and are not necessarily those of Scientific American.

Email   PrintPrint

If you really want to know if someone is into you – as in, wants to have your babies – never mind what they say. It’s all in how they say it. A team of researchers led by Juan David Leongómez, a psychologist at the University of Stirling, has discovered that certain “paralingual” features of the human voice, particularly changes to pitch and modulation, can betray the speaker’s hidden sexual attraction to his or her listener. (Or at least, these qualities of the human voice reveal the speaker’s perception of the listener’s attractiveness.) What’s more, these instinctive, unconscious vocal adjustments actually seem to work in terms of increasing the speaker’s odds of getting laid: listeners prefer and respond more favorably (or in technical terms, in a more “proceptive” fashion) to opposite-sex voices that contain these special subtle acoustics than to those that don’t.

In an article soon to be published in the journal Evolution & Human Behavior, Leongómez and his colleagues discovered that when (heterosexual) men, for instance, are asked to flirt with a beautiful woman, two noticeable things begin to happen to their voices. First, their voices get deeper… or rather their voices achieve a deeper minimal octave than under comparison conditions. And second, men’s voices become more sing-songy or pitch-variable when speaking to a pretty woman, sort of like, well, how you’d speak to a baby. It isn’t quite as pronounced as such prosodic “infant-directed speech” (and it’s probably unwise, I hasten to add, for a man to speak to any woman as if she were a puppy), but nonetheless, the investigators found these male voice adjustments during verbal courtship to be an empirically demonstrable effect. What this means is that not only do men’s voices get deeper when they’re chatting up some lovely woman, but they also get higher compared to when their speech is directed at another male or to an unattractive female listener. This effect appeared in both of the language samples tested – native male English and Czech speakers – and even after controlling for the unscripted content of the men’s speech.

So how do Leongómez and his co-authors interpret this puzzling effect? Why, from an evolutionary perspective, of course. “Producing a low pitch at some point during an interaction [with an attractive female] might provide sufficient indication of physical masculinity while freeing men to ‘play’ with their pitch… because low-pitched masculine voices might be associated with aggression, such modulation could potentially enable men to signal both their masculinity and lack of threat simultaneously.” In other words, “Hey, sexy lady, hear this? Hear how I’m sounding right now? That’s right: I’m a virile, testosterone-fuelled male specimen of our species but, cross my heart, I’ll be sweet to you… and our future offspring.” And indeed, a group of naïve female listeners asked to judge the verbal recordings of male wooers found those with the most significant pitch variability the most attractive.

Interestingly, this so-called paralinguistic courtship modulation effect didn’t occur in women’s voices when they believed that they were speaking to a good-looking man, but it did occur when they were speaking to an attractive woman. That’s to say, when (heterosexual) women thought that they were communicating with an especially pretty member of the same sex, they began to stress their pitch modulation. The reason for this isn’t entirely clear, but it could be, as the authors suggest, that these female speakers’ intended audience is in fact desirable male mates, such that women are attempting to enhance their vocal appeal relative to these highly desirable female competitors. “Pfft. She’s not all that,” in other words. “Check out my natural speaking range.” But that itself doesn’t address the adaptation question. Why would such tonal variability in the free speech of human females be attractive to potential male suitors in the first place? On this, the researchers can only speculate. “Such variability might serve as a marker of social interest,” they write, “or help to capture the attention of the listener, or could more simply reflect genuine autonomic arousal in the speaker.” Future work should be able to better tease apart these alternative explanations, but in any event, these new findings by Leongómez and his colleagues add to a growing body of data showing that the remarkably subtle features of our voices are routinely broadcasting covert messages about our hidden reproductive value and interests.

Jesse Bering About the Author: Jesse Bering is Associate Professor of Science Communication at the University of Otago in New Zealand. He is the author of The Belief Instinct (2011), Why Is the Penis Shaped Like That? (2012) and Perv (2013). To learn more about Jesse's work, visit or add him on Facebook ( Follow on Twitter @JesseBering.

The views expressed are those of the author and are not necessarily those of Scientific American.

Rights & Permissions

Comments 4 Comments

Add Comment
  1. 1. LarryMoniz 3:34 pm 07/11/2014

    What a startling revelation. Humans understanding inflection and vocal tones. Gee, most of my fellow humans have only known that for (how many?) maillenia.

    What organization actually wasted money funding such a study and, other than pregnancy, what functional benefit does it provide??

    Link to this
  2. 2. popseal 5:25 pm 07/11/2014

    Balderdash! It’s simple arithmetic: Wiggles and giggles plus curves plus a six pack equals infatuation not love. The popular definitions confuse love and infatuation. Love is a commitment to the well being of the other, base upon values and integrity growing from the human need for fellowship. Modern ‘love’ is little more than a temporary case of being horny. All righteous families start as two ‘lovers’, moves to two good friends, and culminates in them becoming soul mates. The wars along the way serve to cement the fellowship of the two. These being directly from the Biblical construct, are roundly rejected by a society currently out of emotional, sexual, and relationship control.

    Link to this
  3. 3. Plain-2009 12:38 pm 07/13/2014

    Some girls look at the wallet.
    It is a joke.
    I have not read completely the article neither the commentaries.
    The article is interesting.
    I have always thought that it is very important to pay attention to the tone of the voice.
    Probably it revels more than the content of the message.
    Are there people capable of lying to the extent that they can mislead changing the tone of the voice?
    In some parts of the world have been detected even “leaders” that lie.
    So it very important to pay attention to the sound characteristics of the voice.

    Link to this
  4. 4. annbetz 3:53 pm 07/16/2014

    Also, research on the vagus nerve indicates that broad vocal range may signify higher emotional intelligence. We tend to naturally trust people who have more vocal range, and prosidy (the way we talk to babies and puppies) makes us feel safe at quite a visceral level.

    Link to this

Add a Comment
You must sign in or register as a member to submit a comment.

More from Scientific American


Get All-Access Digital + Print >


Email this Article