Guyana has one of the highest levels of biodiversity in the world. With 1,168 vertebrate species and 814 bird species, it boasts one of the richest mammalian fauna assemblages of any comparably sized area in the world. Guyana is home to six ecoregions: Guayanan Highlands moist forests, Guianan moist forests, Orinoco Delta swamp forests, Tepuis, Guianan savanna, and Guianan mangroves. The Guiana Shield region is little known and extremely rich biologically. Unlike other areas of South America, over 70% of the natural habitat remains pristine. Guyana ranks third in the world with a 2019 Forest Landscape Integrity Index mean score of 9.58/10.