Document Type


Date of Degree Completion

Fall 2015

Degree Name

Master of Science (MS)


Primate Behavior

Committee Chair

R. Steven Wagner

Second Committee Member

Lori K. Sheeran

Third Committee Member

Mary Radeke

Fourth Committee Member

Joseph Lorenz


Tibetan macaque sociosexual behavior begins in infancy, and comprises many of their initial interactions with other group members as infants. Tibetan macaques possess a large sociosexual behavioral repertoire, including a behavior called bridging, which involves infants and juveniles, and is found in only four species. Immature macaques differ in the types, rate, and partner preferences across a variety of behaviors. This study compared rates of sexual behavior among four age and sex classes of 26 immature Tibetan macaques at Mt. Huangshan, China. A total of 643 sex behaviors were observed and evaluated for 5 parameters: total sex behavior rates, initiation rates, rates of different types of sexual behavior, partner preference, and rates within different social contexts. Nine types of sex behaviors were observed with bridging being the most common (n = 179) and self-genital manipulation being the least common (n = 18)(H7 = 38.6, p < 0.05). Sex behaviors occurred at the highest rate within spontaneous (2.9 sex behaviors per hour) and play (2.2 sex behaviors per hour) social contexts relative to grooming, aggressive, and self-directed contexts (H4 = 72.4, p < 0.05). Generally, younger males exhibited higher rates of sex behavior relative to other immature classes across all five aspects, and younger females exhibited lower rates of sex behavior relative to other immature classes across all five aspects. Immature Tibetan macaques engage in many sex behaviors with both immature and adult group members. Further studies are needed on the long-term effects of immature sexual behavior regarding its function and influence on social rank and reproductive success.