The eastern hoolock gibbon[1] is a primate of the Hylobatidae family. Eastern hoolock gibbons don’t have a tail like all other monkeys but have a patch of hair in the anogenital region.
- They have long arms and relatively long legs with elongated hooked hands and opposable thumbs not used for tree swinging.
- The sexes are around the same size but differ significantly in coloration: males are black or blackish, with a white stripe across the eyes.
- Females are lighter in color, ranging from pale and tawny to grey-brown, darker on the neck and chest.
- Both sport black faces. White rings encircling the eyes and mouth of females give their face a mask-like appearance.
