By 1999, the practice had grown to the point that Arizona, Colorado, Maine, Nebraska, Nevada, Rhode Island, and Virginia kept between five and eight per cent of their prison population in isolation, and, by 2003, New York had joined them as well.

NEWYORKER: Hellhole

One population of mammoths lived on in isolation on Russia's remote Wrangel Island until about 5, 000 years ago.

BBC: The mammoth's trunk and eyes are still intact

Its isolation has led to a unique geography and animal population, including the lemur, which took a star role in the 2005 animated Hollywood movie named after the island.

BBC: Pupils met the delegation from the Madagascan embassy