The longer life spans of females compared to males has been attributed to the effects of sex hormones. Since experimental tests of this possibility in humans are unethical, indirect studies have been relied on for evidence. The present study offers such indirect evidence by comparing life spans of female and male opera singers, since sex hormones are known to influence development of voice. Life spans of sopranos were found to be significantly greater than those of lower voice registered contraltos, even after controlling for birth year. Differences among male opera singers were not statistically significant. The data support the hypothesis that females live longer than males because of the beneficial effects of estrogens on longevity-related genes.