Abstract
We studied masturbatory behavior of males over a 14-mo period in free-ranging Japanese macaques (Macaca fuscata yakui) on Yakushima island, Japan. We distinguished 2 types: (1) masturbation only and (2) masturbation with final ejaculation. Both types occurred in all 15 adult troop males. We calculated masturbation only as an index (M/h). It occurred over the whole year; however, it was more frequent during the mating than during the non-mating periods. Masturbation with ejaculation was restricted to the mating period. Male mating success correlated positively with social status. Both rate of masturbation only and masturbatory ejaculations increased as male social status and male mating success declined. Lower-ranking males had higher rates of masturbation only, i.e., they spent more time masturbating than higher-ranking males did. Lower-ranking males also had higher proportions of ejaculates for masturbation, while higher-ranking males used most of their ejaculates for mating.
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REFERENCES
Altmann, J. (1974). Observational study of behavior: Sampling methods. Behaviour 49: 227–265.
Baker, R. R., and Bellis, M. A. (1993). Human sperm competition: Ejaculate adjustment by males and the function of masturbation. Anim. Behav. 46: 861–885.
Berard, J. D., Nurnberg, P., Epplen, J. T., and Schmidtke, J. (1994). Alternative reproductive tactics and reproductive success in male rhesus macaques. Behaviour 129: 177–201.
Bercovitch, F. B. (1989). Body size, sperm competition, and determinants of reproductive suc-cess in male savanna baboons. Evolution 43: 1507–1521.
Bielert, C., and van der Walt, L. A. (1982). Male chacma baboon (Papio ursinus)sexual arousal: Mediation by visual cues from female conspecifics. Psychoneuroendocrinology 7: 31–48.
Carpenter, C. R. (1942). Sexual behavior of free ranging rhesus monkeys (Macaca mulatta). J. Comp. Psychol. 33: 143–164.
Conover, W. J. (1980). Practical Nonparametric Statistics, Wiley, New-York.
Dunbar, R. I. M. (1984). Reproductive decisions: An economic analysis of gelada Baboon strate-gies, Princeton University Press, Princeton NJ.
Gage, M. J. G. (1994). Associations between body size, mating pattern, testis size and sperm lengths across butterflies. Proc. R. Soc. Lond. B 258: 247–254.
Harcourt, A. H., Harvey, P. H., Larson, S. G., and Short, R. V. (1981). Testis weight, body weight and breeding system in primates. Nature 293: 55–57.
Linnankoski, I., Grönros, M., and Pertovãara, A. (1993). Eye contact as a trigger of male sexual arousal in stump-tailed macaques. Folia primatol. 60: 181–184.
Manson, J. (1996). Male dominance and mount series duration in Cayo Santiago rhesus macaques. Anim. Behav. 51: 1219–1231.
Maple, T. (1977). Unusual sexual behavior of non-human primates. In Money, J. and Musaph, H. (eds.), Handbook of Sexology, Exerpta Medica, Amsterdam.
Martin, P., and Bateson, P. (2002). Measuring Behaviour, Cambridge University Press, Cambridge, UK.
Maruhashi, T. (1980). Feeding behavior and diet of the Japanese monkey (Macaca fuscata yakui)on Yakushima Island, Japan. Primates 21: 141–160.
Matsubayashi, K., and Enomoto, T. (1983). Longitudinal studies on annual changes in plasma testosterone, body weight and spermatogenesis in adult Japanese monkeys (Macaca fuscata fuscata) under laboratory conditions. Primates 24: 521–529.
Mootnick, A. R., and Baker, E. (1994). Masturbation in captive Hylobates(Gibbons). Zoo. Biol. 13: 345–353.
Nieuwenhuijsen, K., de Neef, K. J., van der Werff, J. J., Bosch, T., and Slob, A. K. (1987). Testosterone, testiz size, seasonality, and behavior in group-living stumptail macaques (Macaca arctoides). Horm. Behav. 21: 153–169.
Ohsawa, H., Inoue, M., and Takenaka, O. (1993). Mating strategy and reproductive success of male patas monkeys (Erythrocebus patas). Primates 34: 533–544.
Parker, G. A. (1970). Sperm competition and its evolutionary consequences in the insects. Biol. Rev. 45: 525–567.
Parker, G. A. (1982). Why are there so many tiny sperm? Sperm competition and the mainte-nance of two sexes. J. Theor. Biol. 96: 281–294.
Pound, N., Javed, M. H., Ruberto, C., Anis Shaikh, A., and Del Valle, A. P. (2002). Duration of sexual arousal predicts semen parameters for masturbatory ejaculates. Physiol. Behav. 76: 685–689.
Ransom, T. W. (1981). Beach Troop of Gombe, Bucknell University Press, Lewisburg, PA.
Ridley, M. (1999). Book review: Sperm competition and sexual selection. Nature 397: 576–577.
Soltis, J., Mitsunaga, F., Shimizu, K., Yanagihara, Y., and Nozaki, O. (1999). Female mating strategy in an enclosed group of Japanese macaques. Am. J. Primatol. 47: 263–278.
Soltis, J., Thomsen, R., Matsubayashi K., and Takenaka, O. (2000). Infanticide by resident males and female counter-strategies in wild Japanese macaques (Macaca fuscata). Behav. Ecol. Sociobiol. 48: 195–202.
Soltis, J., Thomsen, R., and Takenaka, O. (2001). The interaction of male and female reproduc-tive strategies and paternity in wild Japanese macaques, Macaca fuscata. Anim. Behav. 62: 485–494.
Thomsen, R., Soltis, J., and Teltscher, C. (2003). Sperm competition and the function of male masturbation in non-human primates. In Jones, C. B. (ed.), Sexual Selection and Reproductive Competition in Primates: New Perspectives and Directions, ASP-Book Se-ries, Special Topics in Primatology, Vol. 3: pp. 436–453.
Tokuda, K. (1961). A study of the sexual behavior in the Japanese monkey troop. Primates 3: 1–40.
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Thomsen, R., Soltis, J. Male Masturbation in Free-Ranging Japanese Macaques. International Journal of Primatology 25, 1033–1041 (2004). https://doi.org/10.1023/B:IJOP.0000043350.75897.89
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DOI: https://doi.org/10.1023/B:IJOP.0000043350.75897.89