title: Life history of wild Sumatran orangutans (Pongo abelii).
abstract: We present life history data on wild Sumatran orangutans gleaned from a 32-year and a 5.5-year study. Estimated age at first reproduction was 15.4 years. At 9.3 years, the average interbirth interval for this population is the longest ever recorded for any great ape population, significantly longer than that of a Bornean orangutan population. We find that age-specific mortality of Sumatran orangutans does not differ between sexes and is significantly lower than that of wild chimpanzees. We conclude that orangutan life history is the slowest among extant great apes. In accordance with their slow life history, longevity in the wild is estimated to be at least 58 years for males and at least 53 for females. We find no evidence for menopause. These data suggest that compared to the ancestral state, humans have undergone less of an increase in longevity than commonly assumed, and have experienced selection on earlier cessation of reproduction.
authors.affiliation: Utrecht University, Behavioural Biology, P.O. Box 80086, 3508 TB, Utrecht, The Netherlands.
authors.forename: S A
authors.initials: SA
authors.lastname: Wich
authors.forename: S S
authors.initials: SS
authors.lastname: Utami-Atmoko
authors.forename: T Mitra
authors.initials: TM
authors.lastname: Setia
authors.forename: H D
authors.initials: HD
authors.lastname: Rijksen
authors.forename: C
authors.initials: C
authors.lastname: Schürmann
authors.forename: J A R A M
authors.initials: JA
authors.lastname: van Hooff
authors.forename: C P
authors.initials: CP
authors.lastname: van Schaik
mesh_terms: D000818:Animals; D005075:Biological Evolution; D005260:Female; D006801:Humans; D007214:Indonesia; D015993:Life Tables; D008136:Longevity / Q000502:physiology; D008297:Male; D002679:Pan troglodytes / Q000254:growth & development; D011148:Pongo pygmaeus / Q000254:growth & development / Q000502:physiology*; D011247:Pregnancy; D012098:Reproduction / Q000502:physiology; D012744:Sex Ratio