Some general features of islands and island animals are discussed. The Mediterranean islands carried various intriguing mammal faunae in the Neogene and the Quaternairy, that are all extinct now. Some were exterminated by men. A number of examples of specialized island mammals is described, and it is attempted to account for their peculiar morphologies by invoking special island factors that called for adaptive changes. Degeneration is not typical for the fossil mediterranean island mammals.