... that which they had been collecting in the hill country near Corumba, seventy or eighty miles distant; and birds swarmed, both species and individuals. South America has the most extensive and most varied avifauna of all the continents. On the other hand, its mammalian fauna, although very interesting, is rather poor in number of species and individuals and in the size of the beasts. It possesses more mammals that are unique and distinctive in type than does any other continent ... — Through the Brazilian Wilderness • Theodore Roosevelt