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 were subsequently dispatched to occupy Germany's other territories including the New Guinea mainland, New Ireland, the Admiralty Islands, the Western Islands, Bougainville, and the German Solomons. The colony remained under Australian military control until 1921. At the 1919 Paris Peace Conference following the war, Australian Prime Minister Billy Hughes sought to secure possession of New Guinea from the defeated German Empire: telling the Conference: "Strategically the northern islands (such as New Guinea) encompass Australia like fortresses. They are as necessary to Australia as water to a city." Article 22 of the Treaty of Versailles provided for the division of Germany