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Study: Lower voice may mean lower sperm quality


(CBS) Does that stranger with the deep, soothing voice sound like a potential mate? Don't let your ears pick your next potential partner for you: Males with deeper voices might be the preferred type, but they have, on average, worse sperm than their squeaky counterparts, a new study has found.

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According to an article on the Scientific American blog, a lower pitched voice is normally associated with a more masculine, taller and attractive man. Research has shown that women in North America prefer deeper-voiced men as short term partners, and research on the Hazda people of Tanzania has shown that men with lower timbre and pitched vocals have more living offspring. However, that might be because lower pitched men are getting selected more by the ladies, and have more chances to procreate.

For the study, published in the Dec. 22 issue of the journal PLoS One, researchers made voice recordings of 54 heterosexual Australian males 18 to 32 years of age. A semen analysis showed that sperm from deeper voiced males scored lower on seven "motility parameters," meaning the sperm were less likely to link up with an egg. This effect has been seen in dominant males throughout the animal kingdom, from artic charr to cockroaches, according to the researchers. The more attractive the male gets, the lower his sperm quality.

The researchers concluded that the link between deep voices and worse sperm might be an evolutionary trade-off. Human bodies have limited resources, so with this effect, more resources may be dedicated towards features that attract a mate, at the expense of the what's needed to mate,

Lesson to be learned: Don't overlook the guy that sounds like Mickey Mouse.