[3] Researchers estimate H. tianxing diverged from H. leuconedys roughly 490,000 years ago.

[4] The Eastern hoolock is vulnerable on the IUCN Red List, with a population of 310,000–370,000 individuals.

[10][11] The name is a reference to brachiation, the main locomotory mode of gibbons, and derived from the text of the I Ching, an ancient Chinese book of divination.

[3] In the adult female H. tianxing, their ventral pelage is coloured yellow/white or reddish blonde.

[3] Females also have distinctive incomplete white face rings, with sparse hairs on their lateral orbital and suborbital regions.

[3] The Skywalker hoolock gibbon can be found in the montane forests of eastern Myanmar and southwestern China in the Mt.

[5] 11 solitary and 32 groups of Skywalker hoolock gibbons have been recorded in the wild, but their total population is composed of less than 150 individuals.

[5] During the cold season in Yunnan province, from November to March, the H. tianxing choose sleeping trees closer to food trees and at a lower elevation where it is warmer, and choose to sleep longer and huddle together to thermoregulate.

[14] The Skywalker hoolock gibbon is an endangered species, with less than 150 individuals reported in the wild.

[3] They are threatened by an abundance of illegal hunting and trading of the species,[3] and their habitat is prone to destruction for the use of cardamon cultivation.