Have you ever heard of the word "homogenocene"? Neither had I until I read this book by Charles C. Mann. It describes the ecological era we are now living in where biological diversity is diminishing and the world's ecosystems are beginning to resemble each other. In his first book 1491 Mann describes the world before Columbus "discovered" the Americas and in this tome we learn how the world has changed since the voyage of Cristobal Colon. Can you imagine Italian cooking without tomatoes? or the Irish without the potato? Both these foods were introduced to Europe as a result of the Colombian Exchange, a phenomenon that occurred as ships began to ply the oceans in a quest for gold and silver to fill the coffers of European monarchs. While precious metals were being plundered and New World civilisations were being destroyed a process began that altered the world as it was known then. This book explains how the Spanish not only took silver from South America back to Spain but also sailed to the Philippines where they met Chinese merchants who traded silk and porcelain for the silver. The silver became the basis for the Chinese economy. The most interesting thing about the book is how it explained that the biggest changes occurred from the plants, animals, and diseases that were often transported in both directions across the seas. Coffee came from the Near East to South America, potatoes from the Andes to Europe, Sugar from Asia to the Caribbean. Diseases killed millions after being introduced to people who had no natural immunity to them. 1493 is an interesting read. Over 400 pages but it will hold you interest to the end.