The Borneo rainforest is 130 million years old, making it the oldest rainforest in the world and 70 million years older than the Amazon rainforest. Borneo is very rich in biodiversity compared to many other areas, there are about 15,000 species of flowering plants with 3,000 species of trees (267 species are dipterocarps), 221 species of terrestrial mammals and 420 species of resident birds in Borneo. It is also the centre of evolution and radiation of many endemic species of plants and animals. Subject to mass deforestation, the remaining Borneo rainforest is one of the only remaining natural habitat for the endangered Bornean Orangutan. It is also an important refuge for many endemic forest species, as the Asian Elephant, the Sumatran Rhinoceros, the Bornean Clouded Leopard, and the Dayak Fruit Bat.