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
Territory of New Guinea took possession of the northeast quarter of New Guinea and it became known as German New Guinea. In 1884, the British government proclaimed a protectorate over the southeastern quarter of New Guinea. The protectorate, called British New Guinea, was annexed by Britain outright on 4 September 1888. The territory was transferred to the newly federated Commonwealth of Australia on 18 March 1902, and British New Guinea became the Australian Territory of Papua, with Australian administration beginning in 1906. One of the first actions of Australia's armed forces during World War I was the seizure by the Australian Naval and Military