![]() ![]() Some birds became flightless, like the celebrated dodo native to Mauritius. Some reptiles isolated on islands grew large, like the Komodo dragon of Indonesia some mammals shrank, like the pygmy elephants found in Sicily. ![]() Islands that sit on continental shelves near enough to mainlands to have been connected by land bridges at times of major glaciation may have animal species as varied as those on the mainland, but the species are likely to differ in their behavior or appearance from mainland relatives. So it was with the varied populations of finches that Charles Darwin observed in the Galapagos. On oceanic islands, which arise from deep sea eruptions (such as the Galapagos Islands), there may be fewer varieties of species the first arrivals often expand to fill all sorts of ecological niches in a process called adaptive radiation. There are unique evolutionary opportunities as well as pressures on islands. ![]() The National Magazine Award-winning science writer ( Outside magazine The Flight of the Iguana, 1988, etc.) asks, Why does island life differ radically from mainland life? The answer, not surprisingly, is evolution. ![]() Everything you might want to know about life and death on islands here, there, and everywhere on the globe can be found in Quammen's study of island biogeography. ![]()
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