Little gibbons
Little gibbons | ||||||||||||
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White-handed gibbon ( Hylobates lar ) |
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Systematics | ||||||||||||
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Scientific name | ||||||||||||
Hylobates | ||||||||||||
Illiger , 1811 |
The small gibbons ( Hylobates ) are a genus of primate from the family of gibbons (Hylobatidae). Six to nine species are grouped together in this genus.
features
Small gibbons show the typical body structure of the gibbons with their slim body, long arms and the missing tail. With a weight of 4.5 to 7 kilograms, they are the lightest members of their family. The fur color varies between yellowish-gray, brown and black. The coloration is more variable than that of the other genera, it can also be clearly different within a species. There are differently colored animals in the white-hand and black-hand gibbon in particular, in one species, the cap gibbon, the sexes are differently colored. In general, however, there is no pronounced sexual dimorphism , males and females are approximately the same size.
distribution and habitat
The small gibbons have the largest distribution area of all gibbo genera, it stretches across the Southeast Asian mainland ( Thailand , the extreme south of Yunnan , eastern Myanmar , western Cambodia and the Malay Peninsula ) to the islands of Sumatra , Borneo and Java . In the west the Saluen river and in the east the Mekong form the limit of their distribution area. The habitat of these animals are tropical rainforests .
Way of life
Like all gibbons, the little gibbons are diurnal tree dwellers who rarely come to the ground and mainly move through the branches by swinging (brachiation). They live in fixed family groups (one pair of parents and one to three young animals) that live in a fixed territory of 20 to 40 hectares in size. The males emit loud solo chants at sunrise to mark the territory and also for pair bonding, the duet chants with the females sound a few hours later (in the case of silver and lump gibbons, these duet chants are absent in contrast to all other gibbons).
The diet of these animals consists mainly of fruits, but they also eat leaves and other plant material as well as small animals.
After a gestation period of around seven months, the female gives birth to a single young. In some species (such as the capped gibbon) this can be clearly different in color from the adult animals. The young animal is weaned after around two years and sexual maturity occurs at six to eight years of age.
threat
Like all gibbons, the little gibbons are primarily endangered by the destruction of their habitat. The silver gibbon living on Java is particularly threatened, but the lump and cap gibbon are also listed as endangered by the IUCN .
Systematics
The genus of the small gibbons ( Hylobates ) is divided into six to nine species:
- Kloss gibbon ( H. klossii )
- Cap gibbon ( H. pileatus )
- Müller gibbon ( H. muelleri )
- Western Borneo Gibbon ( H. abbotti )
- Eastern Borneo Gibbon ( H. funereus )
- Silver gibbon ( H. moloch )
- Black-handed gibbon ( H. agilis )
- White-bearded gibbon ( H. albibarbis ; is often listed as a subspecies of the black-handed gibbon)
- White-handed gibbon ( H. lar )
Traditionally, all gibbons were grouped together in the genus Hylobates . Due to differences in the number of chromosomes, in the structure of the skull and in body size, the crested gibbons ( Nomascus ), white-browed gibbons ( Hoolock ) and Siamangs ( Symphalangus ) are listed as separate genera.
literature
- Thomas Geissmann: Comparative Primatology . Springer, Berlin 2003. ISBN 3540436456
- DE Wilson & DM Reeder: Mammal Species of the World . Johns Hopkins University Press, 2005. ISBN 0801882214