The Huli Beast
In the remote highlands of Papua New Guinea, the remains of a giant marsupial came to light. Hulitherium tomasetti was a member of the Diprotodontidae family, a group of large-bodied herbivores whose best known member is the massive Diprotodon. Hulitherium, however, belonged to a distinct subfamily, the Zygomaturinae. It was a substantial animal, estimated to stand about one meter tall at the shoulder, stretch two meters long, and weigh between 75 and 200 kilograms. Its anatomy suggests it was more mobile than some of its larger, more heavily built relatives.
The first fossils were discovered by local Huli people in 1967 while widening an airstrip at Pureni Mission in the Southern Highlands Province. The genus name, Hulitherium, honors them, meaning "Huli beast". The species name, tomasetti, recognizes Father Berard Tomasetti, a missionary who understood the discovery's significance and brought the fossils to scientific attention. Analysis of the site, a former lake bed filled in by ancient lava flows, places the animal in the Late Pleistocene. A log found in the same deposit was radiocarbon-dated to approximately 38,600 years ago.
A Browser's Toolkit
The teeth and skull of Hulitherium show it was a browser. Its diet consisted of foliage, leaves, and shoots found in its montane rainforest habitat. An earlier idea that it specialized in bamboo, like a giant panda, is now considered less likely, though bamboo may have been part of a more generalized diet. The structure of its teeth and powerful jaw muscles were adapted for processing this kind of vegetation.
Hulitherium was part of a diverse megafaunal community that populated the ancient landmass of Sahul, which connected New Guinea and Australia. Fossils of other large marsupials, such as other zygomaturines (Zygomaturus and Maokopia) and extinct giant kangaroos (Protemnodon), have also been found in New Guinea. The evidence from sites like the Nombe Rockshelter suggests that some of these giant species may have survived in the New Guinea highlands for thousands of years after their Australian relatives vanished. This extended survival might be due to the rugged terrain and lower human population density compared to many parts of Australia at the time. The eventual disappearance of these animals likely coincided with significant climate and environmental changes at the end of the last ice age.