It rises from the southern end of the Atacama Plateau (Puna de Atacama), a plateau that lies next to the Atacama Desert, where the average altitude is 4,000 meters.
In 2011, researchers discovered two new species of freshwater stingrays in the Amazon River.
The Heliotrygon (rosai and gomesi), commonly referred to as the Pancake stingrays, is the first new genus of stingrays from the Amazon described since 1987.
In 1951, American John Goddard and two French explorers were the first to swim the entire river successfully.
The 9-month expedition began at the source of the Nile in Burundi. Explorers covered about 6 800 km (4 225 mi) before reaching the mouth at the Mediterranean Sea.
