University of Texas psychologist Davis Buss compared three groups of women—ages 18 to 26, 26 to 45, and 46 and older—and reported the results earlier this year in the journal, Personality and Individual Difference. He and his colleagues discovered that women in their thirties and forties were significantly more sexual than younger and older females.

What fascinated [them] both was ... "Older men presumably continue to lust because they are evolutionarily programmed to keep spreading their genes until they drop dead—but why would women continue to lust, beyond an interest in procreation, beyond minilaproscopy tubal ligation, beyond menopause, outside marriage—and from the male viewpoint perhaps, beyond all reason?"