Heat Loss May Explain Bill Size Differences between Birds Occupying Different Habitats

• Russell Greenberg ,

  * E-mail: greenbergr@si.edu

  Affiliation Smithsonian Migratory Bird Center, Smithsonian Conservation Biology Institute, National Zoological Park, Washington, DC, United States of America

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• Viviana Cadena,

  Affiliation Department of Biological Sciences, Brock University, St. Catharines, Ontario, Canada

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• Raymond M. Danner,

  Affiliations Smithsonian Migratory Bird Center, Smithsonian Conservation Biology Institute, National Zoological Park, Washington, DC, United States of America, Avian Ecology Group, Department of Biological Sciences, Virginia Polytechnic Institute and State University, Blacksburg, Virginia, United States of America

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• Glenn Tattersall

  Affiliation Department of Biological Sciences, Brock University, St. Catharines, Ontario, Canada

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