Men who are capable of hitting lower notes tend to father more children than their higher-pitched counterparts, according to a new study from a Harvard Ph.D. candidate.

By recording the voices of 49 men in the Tanzanian Hadza community and comparing their reproductive histories, anthropology graduate student Coren L. Apicella discovered that men with deeper voices fathered two more children on average than men with higher voices. The reason for this, however, is still unknown.

In the study, Apicella and her co-authors speculate that men with deeper voices may begin procreating earlier—or perhaps, women prefer men with deeper voices.

Frank W. Marlowe, an anthropology professor at Florida State University and an author on the study, said that the “handicap principal” may play a part in the results.

Marlowe explained in an interview that a deeper voice can indicate higher testosterone levels. While testosterone helps men put on muscle and makes them more aggressive, having too much can “handicap” the immune system.

“Only males who could withstand the negative fallout of higher testosterone levels are showing the signals of having better genes to resist disease,” Marlowe said.

As a result, a deep voice could let women judge the strength of men’s immune systems, naturally increasing the chances of having a healthy child.

But singers around the Harvard campus said that women care about more than just deep voices.

“Obviously, a boy who has a high voice who is physically attractive would be more appealing to me than a boy who has a low voice and is not physically attractive,” said Anne E. P. Stone ’10, a singer for the Pitches.

Still others said the study’s results seemed intuitively correct.

“There are plenty of attractive tenors out there, but I guess you often hear ‘he has such a deep voice’ in a positive sense,” said Kelsey A. Maguire ’11, who sings for the a cappella group, the Fallen Angels.

James S. Williams ’10, a bass singer in the Krokodiloes, said his own experiences suggest the study might be right.

“Women certainly find me attractive,” he said.

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