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This study was supported by the U.S. Department of Agriculture, Agricultural Research Service (USDA-ARS) under Award No. 59-0790-3-201 and the U.S. Geological Survey (USGS) under Grant Agreement No. 03HQGR0131. The content of this publication does not necessarily reflect the views or policies of the USDA-ARS or USGS, nor does mention of trade names, commercial products or organizations imply endorsement by the U.S. Government.
International Standard Book Number-13: 978-0-309-10289-6 (Book)
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Copyright 2007 by the National Academy of Sciences. All rights reserved.
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Cover: Design by Van Nguyen. Photo credits clockwise from top left: hummingbird by W. May; sphinx moth by W. May; bat by Merlin D. Tuttle, Bat Conservation International, reprinted with permission; bee by David Inouye, University of Maryland, College Park.