How big does a Siamang get? Here is an overview over the average adult age:
A grown Siamang (Symphalangus syndactylus) reaches an average size of 82.4 cm (2′ 9″).
When born, they have an average size of 0 cm (0′ 0″). During their lifetime of about 38 years, they grow from 517 grams (1.14 lbs) to 10.84 kg (23.9 lbs). A Siamang has 1 babies at once. The Siamang (genus: Symphalangus) is a member of the family Hylobatidae.
As a reference: Humans reach an average body size of 1.65m (5′ 5″) while carrying 62 kg (137 lbs). A human woman is pregnant for 280 days (40 weeks) and on average become 75 years old.
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The siamang (Symphalangus syndactylus) is an arboreal black-furred gibbon native to the forests of Indonesia, Malaysia and Thailand. The largest of the gibbons, the siamang can be twice the size of other gibbons, reaching 1 m in height, and weighing up to 14 kg. The siamang is the only species in the genus Symphalangus.Two features distinguish the siamang from other gibbons. The first is that two digits on each foot—the second and third toes—are partially joined by a membrane—hence the name “syndactylus”, from the Ancient Greek sun-, “united” + daktulos, “finger”. The second is the large gular sac (found in both males and females of the species), which is a throat pouch which can be inflated to the size of the siamang’s head, allowing it to make loud, resonating calls or songs.Two subspecies of the siamang may exist. If so, they are the nominate Sumatran siamang (S. s. syndactylus) and the Malaysian siamang (S. s. continentis, in peninsular Malaysia). Otherwise, the Malaysian individuals are only a population. The siamang occurs sympatrically with other gibbons; its two ranges are entirely within the combined ranges of the agile gibbon and the lar gibbon.The siamang can live to around 40 years in captivity.While the illegal pet trade takes a toll on wild populations, the principal threat to the siamang is habitat loss in both Indonesia and Malaysia. The palm oil production industry is clearing large swaths of forest, reducing the habitat of the siamang, along with that of other species, such as the Sumatran tiger.
Animals of the same family as a Siamang
We found other animals of the Hylobatidae family:
- Pileated gibbon with a size of 54.2 cm (1′ 10″)
- Black crested gibbon with a size of 54.5 cm (1′ 10″)
- Black crested gibbon with a size of 54.5 cm (1′ 10″)
- Lar gibbon with a size of 54.5 cm (1′ 10″)
- Northern white-cheeked gibbon with a size of 54.5 cm (1′ 10″)
- Hoolock gibbon with a size of 54.7 cm (1′ 10″)
- Siamang with a size of 82.4 cm (2′ 9″)
- Kloss’s gibbon with a size of 51.2 cm (1′ 9″)
- Agile gibbon with a size of 54.4 cm (1′ 10″)
- Northern white-cheeked gibbon with a size of 54.5 cm (1′ 10″)
Animals with the same size as a Siamang
Not that size really matters, but it makes things comparable. So here are a couple of animals that are as big as Siamang:
- Fishing cat with a size of 77.9 cm (2′ 7″)
- Golden jackal with a size of 83 cm (2′ 9″)
- Sharpe’s grysbok with a size of 67.9 cm (2′ 3″)
- Canada lynx with a size of 70.4 cm (2′ 4″)
- Chinese mountain cat with a size of 78.6 cm (2′ 7″)
- Grizzled tree-kangaroo with a size of 71.7 cm (2′ 5″)
- Collared mangabey with a size of 66 cm (2′ 2″)
- Leopard cat with a size of 68.4 cm (2′ 3″)
- Mandrill with a size of 75.8 cm (2′ 6″)
- Patas monkey with a size of 66.5 cm (2′ 3″)
Animals with the same litter size as a Siamang
Here is a list of animals that have the same number of babies per litter (1) as a Siamang:
- Brazilian shrew mouse
- Phayre’s leaf monkey
- Mountain nyala
- Thorold’s deer
- Madagascan rousette
- Weasel sportive lemur
- Blackish deer mouse
- Lesser false vampire bat
- Western grey kangaroo
- Black duiker
Animals with the same life expectancy as a Siamang
Completely different animals, but becoming as old as a Siamang:
- American black bear with an average maximal age of 32 years
- Javan rhinoceros with an average maximal age of 40 years
- Walrus with an average maximal age of 40 years
- Japanese macaque with an average maximal age of 33 years
- Agile gibbon with an average maximal age of 44 years
- Chacma baboon with an average maximal age of 45 years
- Western long-beaked echidna with an average maximal age of 31 years
- Hamadryas baboon with an average maximal age of 40 years
- Yellow baboon with an average maximal age of 45 years
- Campbell’s mona monkey with an average maximal age of 33 years
Animals with the same weight as a Siamang
As a comparison, here are some other animals that weight as much as the Symphalangus syndactylus:
- Pennant’s colobus with a weight of 9.16 kilos (20.19 lbs)
- Red-shanked douc with a weight of 9.48 kilos (20.9 lbs)
- Pudú with a weight of 9.6 kilos (21.16 lbs)
- Water chevrotain with a weight of 10.83 kilos (23.88 lbs)
- Ocelot with a weight of 11.89 kilos (26.21 lbs)
- Bennett’s tree-kangaroo with a weight of 10.48 kilos (23.1 lbs)
- Golden jackal with a weight of 9.67 kilos (21.32 lbs)
- Greater long-nosed armadillo with a weight of 9.7 kilos (21.38 lbs)
- Black-footed gray langur with a weight of 10.03 kilos (22.11 lbs)
- Mountain paca with a weight of 9 kilos (19.84 lbs)
