Non-invasive collection and analysis of semen in wild macaques
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Assessments of primate male fertility via semen analyses are so far restricted to captivity. This study describes a non-invasive method to collect and analyse semen in wild primates, based on fieldwork with Yakushima macaques (Macaca fuscata yakui). Over nine mating seasons between 1993 and 2010, 128 masturbatory ejaculations were recorded in 21 males of 5 study troops, and in 11 non-troop males. In 55 %, ejaculate volume was directly estimated, and in 37 %, pH-value, sperm vitality, numbers, morphology and swimming velocity could also be determined. This approach of assessing semen production rates and individual male fertility can be applied to other primate taxa, in particular to largely terrestrial populations where males masturbate frequently, such as macaques and baboons. Furthermore, since explanations of male reproductive skew in non-human primate populations have until now ignored the potential role of semen quality, the method presented here will also help to answer this question.
KeywordsNon-invasive semen collection Fertility analysis Masturbation Macaques Macaca fuscata yakui Yakushima
The study was funded by a grant (HSP III-D/97/16290) from the German Academic Exchange Service (DAAD), a stipend from the City of Berlin (Berliner Programm zur Förderung der Chancengleichheit für Frauen in Forschung und Lehre, N-16/04), the Japanese Society for the Promotion of Science (JSPS; pilot-1994/96), Shimazu Kyoto (2009–2011), Suzuki Corp. (1999–2001), and a private donor (1997 and 2010). I thank Volker Sommer, Joseph Soltis, Mike Huffmann and Ute Radespiel for their encouragement during different stages of this project. Particular thanks go to Kiyoaki Matsubayashi, Juichi Yamagiwa, Hideki Sugiura, Sachiko Hayakawa, Miki Matsubara, Goro Hanya, and two field assistants as well as to all members of the Yakushima Research Group for support of my work in Japan and on Yakushima over the last two decades. I am grateful to Bettina Wachter and two anonymous reviewers for helpful comments on an earlier draft and to Anahita Kazem for proofreading the manuscript.
- Dixson AF (2012) Primate sexuality. Oxford University Press, OxfordGoogle Scholar
- Eberhard WG (1996) Female control: sexual selection by cryptic female choice. Princeton University Press, PrincetonGoogle Scholar
- Frearson C (2005) Masturbation in male primates: taxonomic distribution, proximate causes and potential evolutionary functions. In: MSc thesis. University College London, Dept of Anthropology, UKGoogle Scholar
- Inoue E (2012) Male masturbation behaviour of Japanese macaques in the Arashiyama E troop. In: Leca JB, Huffman MA, Vasey PL (eds) The monkeys of stormy mountain: 60 years of primatological research on the Japanese macaques of Arashiyama. Cambridge University Press, Cambridge, pp 204–220Google Scholar
- Japan Meteorological Agency (1971–2000): http://www.data.jma.go.jp. Accessed 15 Oct 2012 (in Japanese)
- Short RV (1981) Sexual selection in man and the great apes. In: Graham CE (ed) Reproductive biology of the great apes. Academic Press, London, pp 319–341Google Scholar
- Thomsen R (1996) An ecological comparison of two troops of Yakushima macaques (Macaca fuscata yakui) ranging in different habitats of Yakushima Island, Japan. Diploma thesis. University of Munich, Germany (in German)Google Scholar
- Thomsen R, Soltis J, Teltscher C (2003) Sperm competition and the function of male masturbation in non-human primates. In: Jones CB (ed) Sexual selection and reproductive competition in primates: new perspectives and directions. ASP-Book Series, Special Topics in Primatology 3:436–453 Google Scholar
- World Health Organisation (1999) WHO Laboratory manual for the examination of human semen and sperm-cervical mucus interaction. Cambridge University Press, CambridgeGoogle Scholar
- World Health Organisation (2012) www.who.int/reproductivehealth/hrp/en/