Brazil's immense area is subdivided into different ecosystems, which together sustain some of the world's greatest biodiversity. With abundant fauna and flora, Brazil is home to many thousands of species, most of them still undiscovered. There is general consensus, that Brazil has the highest number of both terrestrial vertebrates and invertebrates of any country in the world. This high diversity of fauna can be explained by the sheer size of Brazil and also the great variation in ecosystems. The numbers published about Brazil's fauna diversity can vary from source to source. Also new species continue to be discovered and, sadly, some species go extinct in the wild. Brazil has the highest primate diversity of any country in the world with 77 species and fresh water fish (over 3000 species), it claims the second-highest number of amphibian species, the third highest number of bird species and is ranked fifth in reptile species. Many of the species that are at risk live in threatened habitats such as the Atlantic Forest.The Amazon is the area possessing the highest concentration of fresh water and the most varied flora and fauna on the planet. As the biggest source of life in the world, the Amazon is one of the few areas on earth where nature can still bring its immeasurable strength fully to the fore.The Sabiá, or Thrush, is known for the beauty of both its plumage and its song. It is found all over Brazil, in 12 species, the best known of which is the Rufous-bellied Thrush, or Sabiá-laranjeira, Brazil’s national bird.