Tree-kangaroo

The tree-kangaroos are marsupials of the genus Dendrolagus adapted for arboreal locomotion. They inhabit the tropical rainforests of New Guinea, far northeastern Queensland and some of the islands in the region. Most tree-kangaroos are considered threatened due to hunting and habitat destruction. Tree-kangaroos are the only true arboreal macropods The evolutionary history of tree-kangaroos begins with a rainforest floor dwelling pademelon-like ancestor.

This ancestor evolved from an arboreal possum-like ancestor as is suspected of all macropodid marsupials in Australia and New Guinea. During the late Eocene the Australian/New Guinean continent began a period of drying that caused a retreat in the area of rainforest. The retreat of the rainforest forced the ancestral pademelons to begin living in a dryer, rockier environment. After some generations of adaptation to the new environment, the pademelons evolved into rock-wallabies (Petrogale spp.). The rock-wallabies developed a generalist feeding strategy due to their dependence on a diverse assortment of vegetation refuges. This generalist strategy allowed the rock-wallabies to easily adapt to malesian rainforest types that were introduced to Australia from Asia during the mid-Miocene. The rock-wallabies that migrated into these introduced forests adapted to spend more time climbing trees. One species in particular, the proserpine rock-wallaby (Petrogale persephone), displays equal preference for climbing trees as for living in rocky outcrops. During the late-Miocene the semi-arboreal rock-wallabies evolved into the now extinct tree-kangaroo genus Bohra. Global cooling during the Pleistocene caused continent wide drying and rainforest retractions in Australia and New Guinea. 

The rainforest contractions isolated populations of Bohra which resulted in the evolution of today's tree-kangaroos (Dendrolagus spp.) as they adapted to lifestyles in geographically small and diverse rainforest fragments, and became further specialized for a canopy dwelling lifestyle. The Seri's tree-kangaroo (Dendrolagus stellarum) has been described as a subspecies of the Doria's tree-kangaroo (D. dorianus), however, some recent authorities have treated it as a separate species based on its absolute diagnostability. 

It has further been suggested that the Wondiwoi tree-kangaroo (Dendrolagus mayri) may represent a valid species, but as it is known only from a single preserved specimen—an adult male collected in 1928 from the Wondiwoi Peninsula of Papuamost authorities have retained it as a subspecies of D. dorianus. The IUCN provisionally treats D. mayri as a separate species, and have assessed it to be "critically endangered, possibly extinct".The case for the golden-mantled tree-kangaroo (Dendrolagus pulcherrimus) is comparable to that of D. stellarum; it was first described as a subspecies of D. goodfellowi, however, recent authorities have elevated it to species status based on its absolute diagnostability. A population of the Tenkile (Scott's tree-kangaroo) recently discovered from the Bewani Mountains may represent an undescribed subspecies.