Displaying extravagant plumage, often in spectacular hues, the 39 species of Birds of Paradise are among the most splendid creatures on Earth. Native only to New Guinea, a few outlying islands, and a small dot of Australia, each species is unique in both form and behavior. Males are opulently feathered and their courtship dances are some of the most elaborate in the bird world. The rare beauty of these birds piqued the interest of 19th century British naturalist Alfred Russel Wallace, the lesser-known coauthor of the theory of natural selection. He traveled to the small Indonesian island of Aru to collect and trade the birds. It was here that he first formulated his ideas for the theory, and wrote to Charles Darwin.