Aggressive tone can reflect your size, strength to others

The aggression in your tone can help the listener determine how strong or weak, tall or short you are than them, with a high degree of accuracy, a study has found.

While many animals – including sea lions, red deer, and dogs – have the ability to judge their competitor through hearing their vocalisations, researchers found that humans can also use nonverbal vocal cues, including aggressive roars, to judge one another's size and physical formidability.

"When other animals produce vocalisations, they're doing so for a reason – they're communicating information about themselves, be it physical condition or internal state," said Jordan Raine from Britain's University of Sussex.

"The information is often 'honest' but as our study shows, vocalisations can also serve to exaggerate traits such as physical formidability," Raine added.

For the study, the team measured the upper-body strength and height of men and women and recorded them producing aggressive roars and aggressive speech sentences.

The findings, reported in the journal iScience, showed that men could correctly determine whether a stranger was physically stronger than themselves 88 per cent of the time when listening to a clip of someone roaring.

On the other hand, women tended to overestimate the strength of a man in a recording, compared to audio clips of female speakers with a similar level of strength.

"Previous investigations have found that humans can estimate height and strength from the voice, but that they don't do it very well," Raine said.

"However, no one has ever investigated to what extent people can judge whether someone is stronger or weaker than themselves – a judgment that may be more relevant to the survival of our ancestors than judging someone's absolute strength or body size," Raine noted.