New Zealand (/njuː ˈziːlənd/; Māori: Aotearoa [aɔˈtɛaɾɔa]) is an island country in the southwestern Pacific Ocean. The country geographically comprises two main landmasses – that of the North Island, or Te Ika-a-Māui, and the South Island, or Te Waipounamu – and numerous smaller islands. New Zealand is situated some 1,500 kilometres (900 mi) east of Australia across the Tasman Sea and roughly 1,000 kilometres (600 mi) south of the Pacific island areas of New Caledonia, Fiji, and Tonga. Because of its remoteness, it was one of the last lands to be settled by humans. During its long isolation, New Zealand developed a distinctive biodiversity of animal, fungal and plant life. The country's varied topography and its sharp mountain peaks, such as the Southern Alps, owe much to the tectonic uplift of land and volcanic eruptions. New Zealand's capital city is Wellington, while its most populous city is Auckland. Polynesians settled New Zealand in 1250–1300 CE and developed a distinctive Māori culture. Abel Tasman, a Dutch explorer, was the first European to sight New Zealand in 1642 CE. In 1840, representatives of the British Crown and Māori Chiefs signed the Treaty of Waitangi, making New Zealand a British colony. Today, the majority of New Zealand's population of 4.5 million is of European descent; the indigenous Māori are the largest minority, followed by Asians and Pacific Islanders. Reflecting this, New Zealand's culture is mainly derived from Māori and early British settlers, with recent broadening arising from increased immigration. The official languages are English, Māori and New Zealand Sign Language, with English predominant. The country's economy was historically dominated by the export of wool, but exports of dairy products, meat, and wine, along with tourism, are more significant today. Nationally, legislative authority is vested in an elected, unicameral Parliament, while executive political power is exercised by the Cabinet, led by the Prime Minister, who is currently John Key. Queen Elizabeth II is the country's head of state and is represented by a Governor-General. In addition, New Zealand is organised into 11 regional councils and 67 territorial authorities for local government purposes. The Realm of New Zealand also includes Tokelau (a dependent territory); the Cook Islands and Niue (self-governing states in free association with New Zealand); and the Ross Dependency, which is New Zealand's territorial claim in Antarctica. New Zealand is a member of the United Nations, Commonwealth of Nations, ANZUS, Organisation for Economic Co-operation and Development, Pacific Islands Forum and Asia-Pacific Economic Cooperation.