The Amazon rainforest is big. Almost unimaginably big. To begin to grasp its immensity, consider these numbers: The Amazon rainforest covers about 2% of the world's surface area, nearly 2.1 million square miles across South America, mostly (nearly 60%) in the country you see here, Brazil. It's an area that accounts for over half the Earth's remaining rainforests. The breadth of biodiversity is incomparable—nearly 16,000 different tree species, 40,000 species of other plants, 2.5 million insect species, and over 2,000 different types of birds and mammals. Incredibly, perhaps a tenth of the planet's known species call the Amazon home, many of which have not even been identified.