Macaronesia
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Macaronesia is a modern invented collective name for several groups of islands in the North Atlantic Ocean near Europe and North Africa. The name comes from the Greek for "blessed islands", a term used by ancient geographers for islands to the west of the Straits of Gibraltar.
Macaronesia consists of five archipelagos:
- Azores, (Portugal)
- Canaries, (Spain)
- Cape Verde, (Republic of Cape Verde)
- Madeira, (Portugal)
- Savage Isles (Portugal). The Ilhas Selvagens lie between Madeira and the Canaries.
The islands of Macaronesia are volcanic in origin, and are thought to be the product of several geologic hotspots. Although Iceland is also a North Atlantic island that sits atop a hotspot, it is not considered part of Macaronesia. Also, Iceland it too far from the other islands.
The climate of the Macaronesian islands ranges from subtropical to tropical. The Azores and Madeira have a generally cooler climate and higher rainfall than the Canaries and Cape Verde.
The islands have a unique biogeography, and are home to several distinct plant and animal communities. None of the Macaronesian islands were part of a continent, so the native plants and animals reached the islands via long-distance dispersal. Laurel-leaved forests, called laurisilva, once covered most of the Azores, Madeira, the Selvagens, and parts of the Canaries. These forests resemble the ancient forests that covered the Mediterranean basin and northwestern Africa before cooling and drying of the ice ages.
Felling of the forests for timber and firewood, clearing vegetation for grazing and agriculture, and with the introduction of exotic plants and animals by humans has displaced much of the native vegetation. The laurisilva has been reduced to small pockets. As a result, much of the endemic biota of the islands is seriously endangered or extinct.