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Homosexual behavior in wild Sumatran orangutans (Pongo pygmaeus abelii)
1Wildlife Conservation Society, Bronx, New York, USA. efox@princeton.edu
American Journal of Primatology
|December 18, 2001
Summary
Homosexual behavior has been observed in wild male Sumatran orangutans, indicating it is a natural behavior not limited to captivity. These findings expand our understanding of primate sexual and sociosexual behaviors.
Area of Science:
- Primatology
- Ethology
- Zoology
Background:
- Homosexual behavior has been documented in various primate species.
- Previous observations of homosexual behavior in orangutans were limited, often occurring in captive settings.
- The natural occurrence and social context of homosexual behavior in wild orangutans remained under-investigated.
Purpose of the Study:
- To document and analyze homosexual behavior in wild male Sumatran orangutans.
- To determine if homosexual behavior in orangutans is influenced by captivity or human contact.
- To explore the association of homosexual behavior with other social and affiliative behaviors in wild orangutans.
Main Methods:
- Field observations of wild male Sumatran orangutans were conducted at two distinct study sites.
- Specific instances of homosexual behavior were recorded and analyzed.
- The social and behavioral contexts surrounding homosexual interactions were documented.
Main Results:
- Homosexual behavior was observed in wild male Sumatran orangutans at both study sites.
- These occurrences were independent of captive environments or human presence.
- Homosexual behavior was observed in conjunction with both affiliative and agonistic social interactions.
Conclusions:
- Homosexual behavior is a natural component of the behavioral repertoire of wild male Sumatran orangutans.
- These findings confirm that homosexual behavior is not an artifact of captivity or human influence in this species.
- Orangutans join a growing list of primate species exhibiting homosexual behavior as part of their natural sexual or sociosexual behavior.
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