| patterns of dispersal in sumatran siamangs (symphalangus syndactylus): preliminary mtdna evidence suggests more frequent male than female dispersal to adjacent groups. | gibbons of both sexes have been observed emigrating from their natal groups, but the consequences of dispersal in gibbons are poorly understood, and it is unclear whether these are the same for both sexes. i sequenced a 350-bp fragment of mitochondrial dna from 18 adults in seven siamang (symphalangus syndactylus) groups at the way canguk research station in southern sumatra to assess patterns of matrilineal relatedness among and within siamang groups, and to assess their fit with different patt ... | 2007 | 17171713 |
| flowers are an important food for small apes in southern sumatra. | flowers are included in the diets of many primates, but are not generally regarded as making an important contribution to primate energy budgets. however, observations of a number of lemur, platyrrhine, and cercopithecine populations suggest that some flower species may function as key primate fallback foods in periods of low abundance of preferred foods (generally ripe fruits), and that flowers may be preferred foods in some cases. i report heavy reliance on flowers during some study months for ... | 2009 | 19459180 |
| abrupt decline in a protected population of siamangs (symphalangus syndactylus) in southern sumatra. | between 2011 and 2016, approximately 50% of siamangs in the way canguk research area disappeared, including members of 7 of 12 habituated groups. demographic data from 1998 to 2015 confirm that the population decline in the habituated groups reflects a larger trend in the local population. there was no evidence of hunting of primates in the area, and ecological data do not suggest substantial changes in food availability or predation pressure during this period. from 2011 to 2014, we monitored t ... | 2017 | 28848177 |
| dominance relationships among siamang males living in multimale groups. | intense intolerance among males is considered to be an important mechanism maintaining the uni-male organization traditionally attributed to socially monogamous gibbons. long-term field work, however, has revealed the existence of stable, socially polyandrous groups in at least two populations, raising questions about the mechanism that allows two adult males to co-reside in the same group. i collected 21 months of behavioral data on 7 two-male groups of wild siamangs (symphalangus syndactylus) ... | 2016 | 25598523 |
| clouded leopard predation on a wild juvenile siamang. | i report the first documented case of a wild siamang killed by a clouded leopard. the event, involving a juvenile male (weighing 3.7 kg), occurred at dawn, near a known sleeping tree in a lowland tropical forest in southern sumatra (indonesia). examination of the siamang's body revealed that the first 2 cervical vertebrae were crushed and the face was partially eaten. this attack highlights the potential importance of predation as an evolutionary pressure for hylobatids, and poses some questions ... | 2010 | 21454986 |