Papua New Guinea notable feature in common for the two landmasses is the existence of several species of marsupial mammals, including some kangaroos and possums, which are not found elsewhere. Papua New Guinea is a megadiverse country. Many of the other islands within PNG territory, including New Britain, New Ireland, Bougainville, the Admiralty Islands, the Trobriand Islands, and the Louisiade Archipelago, were never linked to New Guinea by land bridges. As a consequence, they have their own flora and fauna; in particular, they lack many of the land mammals and flightless birds that are common to New Guinea and Australia. Australia and New
Australia–Papua New Guinea relations Australia–Papua New Guinea relations Australia–Papua New Guinea relations are the foreign relations between Australia and Papua New Guinea. Papua New Guinea is Australia's closest neighbour (with roughly 6 km separating the two countries at the nearest point, and with both nations sharing the same continent), and a former dependent territory of Australia. Papua New Guinea has developed much closer relations with Australia than with Indonesia, the only country with which it shares a land border. The two countries are Commonwealth realms, and Papua New Guinea benefits from economic development aid from Australia. The southern half of eastern New Guinea (the