Boundaries between the continents of Earth Boundaries between the continents of Earth The boundaries between the continents of Earth are generally a matter of geographical convention. Several slightly different conventions are in use. The number of continents is most commonly considered seven but may range as low as four when the Americas and Afro-Eurasia are each considered a single continent. According to the definition of a continent in the strict sense, an island cannot be part of any continent, but by convention and in practice most major islands are associated with a continent. There are three overland boundaries subject to definition: While the isthmus between Asia
Australia (continent) in urban centres. West Papua, a province of Indonesia, is home to an estimated 44 uncontacted tribal groups. Australia, the largest landmass in the continent, is highly urbanised, and has the world's 13th-largest economy with the second-highest human development index globally. Australia also has the world's 9th largest immigrant population. The first settlers of Australia, New Guinea, and the large islands just to the east arrived between 50,000 and 30,000 years ago. Archaeological terminology for this region has changed repeatedly. Before the 1970s, the single Pleistocene landmass was called "Australasia", derived from the Latin "australis", meaning "southern", although this word