You can encounter amazing creatures on an expedition cruise. The Amazon River basin, for instance, brims with exotic animals with unusual characteristics. Take the sloth: Sleeping up to 20 hours a day, the world's slowest mammal sports a coat of algae on its fur. The poison dart frog's skin secretes a toxin strong enough to paralyze predators. Other intriguing species include toothy piranhas, huge anacondas and pink dolphins. A vast range of birds and plant life add to jungle's vibrant atmosphere.
The Galapagos are made up of more than 230 volcanic islands and islets about 600 miles off the coast of Ecuador. Due to this isolation, it has species that exist nowhere else on Earth -- about 80 percent of the land birds and 97 percent of the reptiles and land mammals are endemic. Here dwell giant Galapagos tortoises, marine iguanas, flightless cormorants, Galapagos penguins and Darwin finches, named for the naturalist who spent five weeks in the islands in 1835.
In tropical Tahiti, the plants are a main attraction. Travelers can find tree ferns, pandanus, coconut trees, mape (which produce a chestnut-like fruit), the miki miki redwood bush and fe'i or wild banana plants, as well as hibiscus, orchids and temple flowers. There also are around a hundred bird species, some of the more notable being the Murphy petrel, the Tahitian sandpiper, the little heron and the Pacific swallow. Diving around Tahiti, you can expect to find sharks, tuna, barracuda, jackfish, moray eels, rays and sea turtles, among other colorful creatures.
The cold-climate destinations of Antarctica and the Arctic are popular for their unmatched whale-watching opportunities. A variety of sea birds also call these areas home. Six types of penguin can be found in the Antarctica region: emperor, Adelie, chinstrap, gentoo and macaroni. Fur and elephant seals gather on the rugged Antarctic coastline, while walruses make their home far away in the Arctic, also known for its polar bears and arctic foxes.