Phantom islands usually stem from the reports of early sailors exploring new realms.
Islands closely grouped together are called an archipelago.
A hotspot is more or less stationary relative to the moving tectonic plate above it, so a chain of islands results as the plate drifts.
Another example is islands in river deltas or in large rivers.
On the other hand, an island may still be described as such despite the presence of a land bridge, such as Singapore and its causeway or the various Dutch delta Islands, such as IJsselmonde.
Tidal islands are also commonly the sites of fortresses, due to their natural fortifications.
The geological make-up of Continental Islands resembles that of continents with a variety of formations, most often comprised of varying ages of stratifed rock.
Islands closer to the mainland are more likely to receive immigrants from the mainland than those farther away from the mainland.
Plate movement across a hot-spot produces a line of islands oriented in the direction of the plate movement.
Islands range in size from huge landmasses to tiny river islets.
The southernmost chain is the Austral Islands, with its northerly trending part being the atolls in the nation of Tuvalu.
Other phantom islands are probably due to navigational errors, the misidentification of icebergs, fog banks, or to optical illusions.
An example is barrier islands, which are accumulations of sand deposited by sea currents on the continental shelf.
Such islands are commonly invoked in metaphor, literature, and the popular imagination, as a place where individuals or small groups of people find themselves marooned or castaway, cut off from civilization.
Oceanic Islands are those that do not sit on continental shelves but rise to the surface from the floors of the ocean basins.
Continental Islands are thought to have been connected to the nearby continent at some point in time, and separated either recently (in a geologic frame of reference) or in ancient eras.
Recent Continental Islands are surrounded by more shallow seas, usually less than 100 fathoms deep, while ancient continental islands are closer to 1,000 or more fathoms deep.
Phantom islands are islands that were believed to exist, and appeared on maps for a period of time (sometimes centuries) during recorded history, but were later removed after they proved nonexistent.
On smaller islands the chance of extinction is greater than on larger ones.
Ancient Continental Islands however, claim as their occupants animals which are on the whole different from those of the mainland.
The world's ten largest islands, in descending order of size are Greenland, New Guinea, Borneo, Madagascar, Baffin Island, Sumatra, Honshu, Great Britain, Victoria Island and Ellesmere Island.
The families and orders vary greatly from those on the continent while oftentimes animals which are present on these islands are missing from the continent.
Oceanic Islands are those which were never connected to another body of land but formed in mid-ocean.
An example is the Hawaiian Islands, from Hawaii to Kure, which then extends beneath the sea surface in a more northerly direction as the Emperor Seamounts.
Recent Continental Islands are home to the same types of animals—birds, mammals and reptiles—that are represented on the mainland.
Some of the Lesser Antilles and the South Sandwich Islands are the only Atlantic Ocean examples.
Islands may be found in oceans, seas, lakes, or rivers.
Many of the world's larger islands are of the continental type.
Continental islands are bodies of land that lie on the continental shelf of a continent.
Very small islands such as emergent land features on atolls are called islets.
Some arose through the mislocation of actual islands, or other errors in geography.
Another chain with similar orientation is the Tuamotu Archipelago; its older, northerly trend is the Line Islands.
A grouping of geographically and/or geologically related islands is called an archipelago.
Whatever their formative history, islands are popular getaway spots for those seeking respite from the harried lives of the civilized world.