Neil MacGregor's world history as told through things that time has left behind. This week he is exploring vigorous empires that flourished across the world 600 years ago - visiting the Inca in South America, Ming Dynasty China, and the Timurids in their capital at Samarkand and the Ottomans in Constantinople. Today he examines the fledgling empire of Portugal and describes what the European world was looking like at this time. His chosen object is one of the most enduring in art history, and one of the most duplicated - Albrecht Durer's famous print of an Indian rhino, an animal he never had never seen. The rhino was brought to Portugal in 1514 and Neil uses this classic image to examine European ambitions. Mark Pilgrim of Chester Zoo considers what it must have been like to transport such a beast and the historian Felipe Fernandez-Armesto describes the potency of the image for Europeans of the age.