Evidence suggests a solely arboreal lifestyle with frequent upside down suspension, hence the name sloth lemur.

Laurie Godrey states in "The Extinct Sloth Lemurs of Madagascar", "Thus, these animals exhibit the odd behavioral combination of being both specialized leapers and adept climbers and hangers.

[7] The curved bones also helped them gain more torque and speed allowing, them to reach branches at great distances.

The relatively small body of Palaeopropithecus, while large compared to the modern lemur, had a great degree curve because it was smaller in stature.

[7] The Palaeopropithecus species were probably folivorous based on dental morphology,[8] consuming a mixed diet of foliage and fruit to varying degrees.

[10][11] There is also no molar use wear evidence that Palaeopropithecus relied on terrestrial foods (C4 grasses, tubers, rhizomes).

Its dental characteristics could be described from the P. kelyus subfossil maxilla fragmentshowing a parastyle and a highly developed mesostyle.

[16] The reason behind the extinction of the several species of Palaeopropithecus has been attributed to the presence of humans to the island of Madagascar, the earliest evidence of which dates back to 2325±43 yr BP.

[16] Scientists have found fossils of Palaeopropithecus that appeared to have cut marks in them, suggesting flesh removal with a sharp object, indicating that the species was hunted by the earliest colonists to the island of Madagascar as a source for food.

Paul Ayshford Methuen, in 1911, who traveled to Madagascar expressly to collect bones of the extinct lemurs for the Oxford Museum.

[4] The slow locomotion habits of Palaeopropithecus likely made them an easy target for their human predators, who would consume them for food, as well as use the bones for tools.

[18] Also, the introduction of man-made charcoal and fire to the island caused considerable damage to the forests where Palaeopropithecus lived and bred.

However, Yale biologists who extracted DNA from the bones and teeth of 9 subfossil individuals from Palaeopropithecus state that all the giant lemurs analyzed died well over 1,000 years ago.