Endemic (ecology)
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.
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)
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.
*
Endemism in birds*
Biodiversity hotspot
