It's not surprising that the Galapagos and the Amazon rainforest are listed in The Best Places to View Wildlife (gadling): "The Amazon Jungle in South Africa (sic) is so vast that it it covers parts of eight countries. It is also the home to the highest concentration of birds and freshwater fish on the planet, and more than one third of the world's animal species call the Amazon home. Highlights of these species include jaguars, anacondas, giant anteaters and a variety of monkeys. The Amazon River contains plenty of interesting creatures as well, such as electric eels, freshwater dolphins, pirarucu, which grow to more than 2 meters in length, and of course the piranha."
"The Galapagos Islands may have made yesterday's list for great places to view penguins too, but they have plenty more to offer as well. Located 600 miles off the coast of Ecuador, the small volcanic archipelago is home to a host of animals that are found no where else on Earth, such as marine iguanas the only lizard in the world that lives in the ocean. There are plenty of lizards that live on land as well, along with several breeds of turtles and sea tortoises, an array of distinct birds, and a large colony of sea lions and fur seals."
Photos of cougars in the Amazon basin and marine iguanas in the Galapagos thanks to ClipArt.com. For more views of the wide variety of wildlife, browse the South American Wildlife Photo Gallery.