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) Australia (continent) The continent of Australia, sometimes known in technical contexts by the names Sahul, Australinea or Meganesia to distinguish it from the country of Australia, consists of the land masses which sit on Australia's continental shelf. This includes mainland Australia, Tasmania, and the island of New Guinea (comprising Papua New Guinea and two Indonesian provinces). Situated in the geographical region of Oceania, it is the smallest of the seven traditional continents in the English conception. The continent lies on a continental shelf overlain by shallow seas which divide it into several landmasses—the Arafura Sea and Torres Strait between mainland