(I)The world's biggest land animal, the elephant, evolved from the mammoth, which appeared millions of years ago. (II) The only survivor of a more primitive species, they once roamed in great herds over the whole of the northern hemisphere. (III) Aiding this research, well preserved fossils have been found in Alaska and Siberia. (IV) They were as large as most dinosaurs. (V) The mammoth became extinct at the end of the Ice Age, and its only descendants, modern elephants, settled in Africa and Asia.