A new study shows men with deep voices tend to have a lower sperm counts than their higher-pitched counterparts. The sperm is just as fertile and mobile, but there are fewer of them swimming around.
That's a surprising discovery. Numerous studies have shown women prefer men with masculine features, such as lots of muscles and that deep voice. And those traits were thought to be present in prime male specimens -- meaning those with plenty of sperm, among other things [source: Dell'Amore].
Researchers already knew that testosterone, a male hormone that lowers your voice pitch, can also lower sperm production. Now they're reasoning that this new finding means men who are biologically programmed to put more effort into attracting women -- by developing lower voices, strong jaws and the like -- may be doing so at the cost of sperm production. This trade-off makes sense from an evolutionary standpoint if the result is that they get the women, and have more status and dominance [source: Dell'Amore].