EXPERIENTIAL VARIABLES INFLUENCING PLAY, FOOT-CLASP MOUNTING AND ADULT SEXUAL COMPETENCE IN MALE RHESUS-MONKEYS

(1) It is concluded that foot-clasp mounting, rather than social play, by juvenile rhesus monkeys is the appropriate index of the affectional development essential for normal adult heterosexual behavior in the male monkey. (2) The opportunity for continuous social interaction with peers, lasting at least three months, resulted in increased frequencies of display of foot-clasp mounts and decreased frequencies of social play by juvenile rhesus monkeys. (3) When the opportunity for continuous social experience was provided during the first year of life, the behavioral changes were manifested immediately and when this opportunity was delayed until late in the second year of life, changes in the frequency of play and mounting were correspondingly delayed. (4) Adult heterosexual competence was greatest in males that had the earliest opportunity for continuous social experience, intermediate in males with delayed social experience, and least in males with no opportunity for continuous social experience with peers. (5) Rearing conditions that produced the highest frequencies of foot-clasp mounting were associated with the highest adult heterosexual competence and rearing conditions that produced the highest frequencies of social play were associated with the lowest adult heterosexual competence. © 1979.