Foreign relations between neighbouring countries Australia and New Zealand, also referred to as Trans-Tasman relations, are extremely close. Both countries share a British colonial heritage as antipodean Dominions and settler colonies, and both are part of the wider Anglosphere. New Zealand sent representatives to the constitutional conventions which led to the uniting of the six Australian colonies but opted not to join. In the Boer War and in both world wars, New Zealand soldiers fought alongside Australian soldiers. In recent years the Closer Economic Relations free trade agreement and its predecessors have inspired ever-converging economic integration. Despite some shared similarities, the cultures of Australia and New Zealand also have their own sets of differences and there are sometimes differences of opinion which some have declared as symptomatic of sibling rivalry. This often centres upon sports and in commercio-economic tensions, such as those arising from the failure of Ansett Australia and those engendered by the formerly long-standing Australian ban on New Zealand apple imports. Both countries are constitutional monarchies and Commonwealth realms – sharing the same person as the sovereign and independent head of state – with parliamentary democracies based on the Westminster system. Their only land border defines the western extent of the Ross Dependency and eastern extent of the Australian Antarctic Territory. They acknowledge two distinct maritime boundaries conclusively delimited by the Australia–New Zealand Maritime Treaty of 2004. In 2017, a major poll showed that New Zealand was considered Australia's "best friend", a position previously held by the United States. History The History of Indigenous Australians is generally thought to be rich to the extent of at least 40,000–45,000 years duration, whereas Polynesian Māori arrived in Aotearoa/New Zealand in several waves by means of waka in waves roughly between 1320 and 1350. Indigenous Australians and Polynesian Māori indigenous to New Zealand are not recorded to have met or interacted prior to 17th and 18th century European exploration of Australia. Regarding the respective indigenous populations, while it may be said that there is a single Māori language and the iwi have been able to present as a unified population represented by a monarch neither has ever been able to be said of the Australian Aboriginal languages or their corresponding population groups. The first European landing on the Australian continent occurred in the Janszoon voyage of 1605–06. Abel Tasman in two distinct voyages in the period 1642–1644 is recorded as the