In fact, the authors of the study, based at the University of California, Santa Barbara, suggest that we might rely on reliable guesses of a man’s strength to draw conclusions about his height and weight. Surprisingly, the results aren’t affected when by culture or language - the researchers tested male voices from the US, Romania and Latin America and found the results replicated across the board. It’s even possible to guess a woman’s strength from her voice, although much less reliably than for males.
There are obvious evolutionary advantages to being able to assess a man’s strength from his voice, as this allows us to guess his fighting ability and make a considered decision in an aggressive situation. Furthermore, the same nerves that control the vocals cords are directly involved in the ‘fight or flight’ nervous system, which means that we might even be able to find out more about a man’s brawling capabilities by listening to him than looking at him – for instance, blood pressure, heart rate and fear-related tension may also be related to vocal performance.
Despite these intriguing connections between voice and fighting ability, the specific acoustic features we use to estimate strength are not yet known. However, as lead author Aaron Sell suggests, “natural selection clearly built specializations into the human neurocognitive architecture designed for assessing fighting ability based on these clues”.