Siamang Gibbon

Scientific name: Symphalangus syndactylus

Conservation status:endangered

Life expectancy: 25-30 years

Gestation period: 210 days


  • Sumatran siamang
  • Nominate siamang

Lifestyle and Location:

This gibbon lives in the forests of Malaysia, Thailand and Sumatra. It is more frugivorous than its relative the lar gibbon with 60% of its diet consisting of fruit with its major fruit being the fig. They use 50% of their day resting and on the rare occasions that they go down to the ground they avoid water, as they cannot swim, and they put both arms above their head for balance and walk on 2 legs.


These guys can reach up to 1 meter in height but usually between 73 and 90 cm and weighs 14 kg. Its hair is the darkest shade of all the gibbons and is long, shaggy and dense. They have a large gulgar sac (throat pouch) used for making louder calls or songs and has 2 digits on each foot that is partially joined by membrane.

Joss‘s Facts

  • It is the largest gibbon of all 14 species and can be twice the size of other gibbons.
  • Their gulgar sac used for louder calls or songs can inflate to the size of their head.
  • The Siamang gibbon becomes independent from its parents by the third year of its life. They have opposable thumbs and toes which the other gibbons lack
  • Can change direction mid jump.
  • They eat over 160 species of  different plants!