With the glacial fluctuations, and far apart from the Indian subcontinent, pushed two taxa apart,[clarification needed] but both retained key adaptation to folivory, and a ruminant-like stomach.

In Sri Lanka, tufted gray langurs are abundant in dry zone forests and also within human dwellings.

Many numerous troops are found at archeologically important areas, such as Polonnaruwa, Dambulla, Anuradhapura, and Sigiriya.

Generally a shy animal, tufted gray langurs are partially arboreal, semi-terrestrial and diurnal in habit.

Unlike the canopy-dweeling sympatric relatives, they are rather common in urban settlements, found in gardens, and other large fruit trees such as Mangifera indica, and Artocarpus heterophyllus.

Other than them, siblings and sub adults are attacked by tigers, dhole, gray wolves, mugger crocodile, and Indian rock python occasionally.

Females quickly attain their heat and mate with new alpha male, even when they are not ready for the reproduction in the natural estrous cycle.

[12] Female langur gives birth to a single offspring or rarely twins, after a 6 months of gestation period.

[13] Tufted gray langurs communicate with many different ways such as barks, grunts, whoops, whistles and howls.

[4] The tufted gray langur monkey's superior eyesight and ability to sit atop high trees allows it to spot predators easily.

Researchers have noted that this species will often sit next to herds of the spotted deer and notify them when a predator is approaching.

In return, the Spotted Deer's excellent sense of smell allows it to detect predators early on and warn the langur that something may be approaching.