- Kingdom Animalia
- Phylum Chordata
- Class Mammalia
- Order Primates
- Family Hylobatidae
 
Gibbons, lesser apes
Gibbons differ from great 
apes in being smaller and generally monogamous and in not making nests. The species include the siamang, the lar, and the hoolock. The siamang, which is the largest, is distinguished by having two digits on each side stuck together, hence the species name 
syndactylus.
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