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Title: Good, but Columbian Exchange got there first
Review: Thirty years ago, Alfred Crosby published The Columbian Exchange about the populations of both hemispheres, communication of diseases, and long term implications of the initial contact in this rich, readable, scholarly work. 1491 is a knock-off of the previous work, just as DaVinci Code lifted Holy Blood, Holy Grail. Everything old is new again--just give credit where credit is due.
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