Luiz Claudio Marigo / Meeting of waters of the River Solimoes and darker River Negro, Amazonas, Brazil. Rio

Sylvain Cordier / Amazon river dolphin (Inia geoffrensis) leaping out of water, Rio Negro, Amazonas, Brazil.

Nick Gordon / Aerial view of the meeting of waters from Rio Solimoes and Rio Negro (black waters on right), to form the mighty Amazon river, near Manaus, Brazil. Waters do not mix for several miles as the sediment...

Nick Gordon / Sunset over Rio Negro river, Amazonia, Brazil

Pete Oxford / Meeting of the waters of Rio Negro (right) and Solimoes River where they join the river Amazon, Brazil, South America