Tree-kangaroo

Tree-kangaroos are marsupials of the genus Macropods, adapted for arboreal locomotion. They inhabit the tropical rainforests of New Guinea and far northeastern Queensland, along with some of the islands in the region. Most tree-kangaroos are considered threatened due to hunting and habitat destruction. They 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, which 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.), which 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. These species are assigned to the genus Dendrolagus: Seri's tree-kangaroo (Dendrolagus stellarum) has been described as a subspecies of Doria's tree-kangaroo (D. dorianus), but some recent authorities have treated it as a separate species based on its absolute diagnostability. The Wondiwoi tree-kangaroo is among the 25 “most wanted lost” species that are the focus of Global Wildlife Conservation's “Search for Lost Species” initiative. The case for the golden-mantled tree-kangaroo (D. pulcherrimus) is comparable to that of D. stellarum; it was first described as a subspecies of D. goodfellowi, though 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. Tree-kangaroos inhabit the tropical rainforests of New Guinea, far northeastern Australia, and some of the islands in the region, in particular, the Schouten Islands and the Raja Ampat Islands. Although most species are found in mountainous areas, several also occur in lowlands, such as the aptly named lowlands tree-kangaroo. Most tree-kangaroos are considered threatened due to hunting and habitat destruction. Because much of their lifestyle involves climbing and jumping between trees, they have evolved an appropriate method of locomotion. Tree-kangaroos thrive in tree tops as opposed to terrestrial kangaroos which survive on mainland Australia. Two species of tree-kangaroos are found in Australia, Bennett's (D. bennetianus), which is found north of the Daintree River and Lumholtz's (D. lumholtzi). Tree-kangaroos have adapted better to regions of high altitudes. At least 14 known subspecies of tree-kangaroo are living in Papua New Guinea and Australia. Tree-kangaroos must find places comfortable and well adapted for breeding, as they only give birth to one joey per year. They are known to have one of the most relaxed and leisurely birthing seasons. They breed cautiously in treetops during monsoon season. Their habitats are breeding grounds for danger as they can easily fall prey to their natural predators, amethystine pythons, which also climb and live in the forest treetops. Tree-kangaroos are known to be able to live in both mountainous regions and low-land locations.