Sky island

Sky islands are isolated mountains surrounded by radically different lowland environments. This has significant implications for natural habitats. Endemism, altitudinal migration, and relict populations are some of the natural phenomena to be found on sky islands.

The complex dynamics of species richness on sky islands draws attention from the discipline of biogeography, and likewise the biodiversity is of concern to conservation biology. One of the key elements of a sky island is separation by physical distance from the other mountain ranges, resulting in a habitat island, such as a forest surrounded by desert.

Some sky islands serve as refugia for boreal species stranded by warming climates since the last ice age. In other cases, localized populations of plants and animals tend towards speciation, similar to oceanic islands such as the Galápagos Islands.

Origin of the term

The sky island concept originated in 1943 when Natt N. Dodge, in an article in Arizona Highways magazine, referred to the Chiricahua Mountains in southeastern Arizona as a "mountain island in a desert sea".

Sky island (disambiguation)

A sky island is a mountain range isolated by valleys in which other ecosystems are located.

Sky island may also refer to:

See also

Sky Island

Sky Island: Being the Further Adventures of Trot and Cap'n Bill after Their Visit to the Sea Fairies is a children's fantasy novel written by L. Frank Baum, illustrated by John R. Neill, and published in 1912 by the Reilly & Britton Company—the same constellation of forces that produced the Oz books in the first decades of the twentieth century.

As the full title indicates, Sky Island is a sequel to Baum's The Sea Fairies of 1911. Both books were intended as parts of a projected long-running fantasy series to replace the Oz books. Given the relatively tepid reception of the first book in the series, however, Baum tried to attract young readers by including two characters from his Oz mythos in Sky Island—Button-Bright and Polychrome, originally introduced in The Road to Oz (1909).

The book was dedicated to the author's sister, Mary Louise Baum Brewster.

Plot summary

Trot, a little girl who lives on the coast of southern California, meets a strange little boy with a large umbrella. Button Bright has been using his family's magic umbrella to take long-range journeys from his Philadelphia home, and has gotten as far as California. After an explanation of how the magic umbrella works, the two children, joined by Cap'n Bill, decide to take a trip to a nearby island; they call it "Sky island," because it looks like it's "halfway in the sky"—but the umbrella takes them to a different place entirely, a literal island in the sky.