Abstract: | Siamangs exhibit paternal care to the extent that the male of a monogamous unit carries its infant offspring beginning late in the infant's first year of life. Field studies have documented this but without behavioral detail. It has been hypothesized that the transfer is facilitated by a desertion of the infant by the female. An infant siamang born in captivity at the Washington Park Zoo, Portland, Oregon, was observed through its first year of life. The infant transfer to the male was documented in captivity and was associated with a high rate of infant-initiated contact with the male and a high rate of infant retrieval by the female. The study concludes that the infant probably played a key role in facilitating the transfer to the male. |