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
Law of Papua New Guinea development of the customary law according to indigenous Melanesian conceptions of justice and equity has been less thorough than may have been anticipated in 1975; the Underlying Law Act does not yet appear to have had significant effect. Advocacy follows the conventions of the English common law world and is adversarial rather than inquisitorial; German law was wholly displaced by Anglo-Australian law in the former German New Guinea after 1914 when Australia seized the Territory and there are no traces of it in modern Papua New Guinea. The Chief Justice of Papua New Guinea is The Honourable Sir Salamo Injia.