Sexual solicitation by middle-aged and old rhesus females.

The sexual behavior of old and middle-aged ovariectomized estradiol treated females was studied in pair tests with old and middle-aged male rhesus macaques (Macaca mulatta). The ages of the subjects (females, N = 21 and males, N = 16) ranged from 9 to 26 years. We found no significant differences between old and middle-aged females in the overall rates of soliciting sexual behavior, and they solicited sexual behavior as readily from old as from middle-aged males. Old males were less active sexually than middle-aged males, but the two groups did not behave differently toward old and middle-aged females. Old and middle-aged females were equally proceptive toward old and middle-aged males and equally attractive to them. Because the ratio of female presents to male contacts did not differ between the old and middle-aged females, the two groups may be considered equally receptive as well. We found no evidence that the capacity to respond sexually to extradiol treatment is diminished in old rhesus females.