The authors would like to thank John Eisenberg and Devra Kleiman for
their support and encouragement throughout the study. This
investigation was supported by research grants from the West Virginia
School of Osteopathic Medicine (WVSOM), and Friends of the National
Zoo (FONZ). Logistic support was provided by the National Zoological
Park's Conservation and Research Center (CRC), and the departments of
Mammalogy and Zoological Research. Our ability to conduct
physiological research at CRC was made possible by the thoughtful
support and encouragement provided by Chris Wemmer. His excellent
staff at CRC, especially Jack Williams, Junior Allison, and Red
McDaniel, were very helpful in providing hospitality and logistical
support to the senior author and his family during their various
visits to the Center. The assistance of several people at the National
Zoo also is gratefully acknowledged: Mitch Bush and Lyndsay Phillips
not only provided veterinary support throughout the investigation,
but also performed surgical procedures required to implant
temperature-sensitive radio transmitters in several raccoons; Olav
Oftedal made his laboratory available to us at various times and
loaned us equipment to use at CRC; Miles Roberts and his staff
provided care for our captive raccoons in the Department of Zoological
Research during various parts of the investigation. Greg Sanders and
Ken Halama, supported by FONZ assistantships, cared for our captive
raccoons at CRC, provided assistance in the laboratory whenever
needed, and were an invaluable source of aid. Their friendship and
help is gratefully acknowledged. Ellen Broudy and Andy Meyer,
supported by WVSOM and a student work study grant, respectively,
provided assistance in the laboratory. David Brown, John Eisenberg,
Mary Etta Hight, Brian McNab, Steve Thompson, and W. Chris Wozencraft
critically reviewed various phases of the manuscript and provided many
helpful suggestions. We deeply appreciate the work of Jean B.
McConville, whose beneficial editorial suggestions helped us improve
several early versions of the manuscript. We also gratefully
acknowledge Diane M. Tyler, our editor at the Smithsonian Institution
Press, whose expertise helped us mold the manuscript into its final
form. Jill Mellon and Sriyanie Miththalapa, supported by FONZ
traineeships, assisted in measuring the daily cycle of body
temperature in raccoons. The Virginia Commission of Game and Inland
Fisheries gave us permission to use wild-caught raccoons in this
project.
$Materials and Methods$