Endemic (ecology)

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This article is about the ecological meaning of "endemic". See also endemic (epidemiology).

In biology and ecology endemic means exclusively native to a place or biota, in contrast to cosmopolitan or introduced. However, it is also differentiated from indigenous: A species that is endemic is unique to a defined place or region (in other words only found in that place or region) and not naturally found anywhere else, whereas a species that is indigenous to somewhere may be native to other locations as well. Usually the term is applied to a discrete geographical unit, often an island or island group, but sometimes a country, habitat type, or other defined area or zone. For example, we can say that the Orange-breasted Sunbird Anthobaphes violacea is a Fynbos endemic (i.e. exclusively found in the Fynbos vegetation type of southwestern South Africa), or that the Socotra Sparrow Passer insularis is endemic to Socotra (only found in the Socotra island group).

Islands are especially likely to develop endemic types or species because of their geographical isolation. This includes remote island groups, such as Hawaii, the Galápagos Islands and Socotra. The restricted area and vulnerability to the depredations of man and introduced species mean that endemics all too easily can become endangered or extinct.

Endemism can also develop in other biologically isolated areas, such as the highlands of Ethiopia or large bodies of water like Lake Baikal.

Ecoregions with high endemism

According to the World Wildlife Fund, the following ecoregions have the highest percentage of endemic plants:

Fynbos (South Africa)
Hawaii tropical dry forests (United States)
Hawaii tropical moist forests (United States)
Kwongan heathlands (Australia)
Madagascar dry deciduous forests (Madagascar)
Madagascar lowland forests (Madagascar)
New Caledonia dry forests (New Caledonia)
New Caledonia rain forests (New Caledonia)
Sierra Madre de Oaxaca and Sierra Madre del Sur pine-oak forests (Mexico, Guatemala)

Threats to high endemicism regions

Some of the principal threats to these special ecosystems are:

Large scale logging operations
Slash-and-burn techniques sometimes a part of shifting cultivation

Both factors are secondary results of world overpopulation.