Proportion of lower-pitched voices judged as competent, strong and trustworthy. (A value of 0.50 represents no discernible preference for either higher- or lower-pitched voices. Male and female listeners found the lower-pitched female voices to be more competent, stronger and more trustworthy. Male (but not female) listeners found lower-pitched male voices to be more competent and stronger. Neither men nor women found the lower- or higher-pitched male voices to be more trustworthy). *p < 0.05 (one-sample t-test); **p < 0.01 (one-sample t-test).