World Wildlife Fund Ecoregions represents global terrestrial and freshwater ecoregions defined as relatively large areas of land or water in the world that share a large majority of their species, dynamics, and environmental conditions. It contains the terrestrial habitats and some freshwater habitats of the Global 200 ecoregions, a collection of the Earth's most outstanding and diverse terrestrial, freshwater, and marine habitats--areas where the Earth's biological wealth is most distinctive and rich, where its loss will be most severely felt, and where we must fight the hardest for conservation. The data is from the World Wildlife Fund Conservation Science Program 1998 - 1999. For more information, contact http://www.worldwildlife.org.