Gibbons are known for their vocal abilities. Male and female pairs duet to strengthen their bond and defend their territory. The largest of all gibbons, the siamang (Hylobates syndactylus) is also the loudest as its musical calls can be heard through dense rainforest foliage up to two miles away. The siamang is also one of the few gibbon species where both genders are the same color.
- Where to see them: Malaysia and Sumatra
- Height: 2.5 to 3.0 ft
- Weight: Up to 23 lbs
- Lifespan: Up to 25 yrs
- Habitat: Tropical rainforest
- Diet: Primarily fruit and leaves, some invertebrates
- Risk Status: Species at Risk (IUCN—Endangered)