ROLE OF THE PROSENCEPHALON IN SHIVERING 
EPILOGUE 
DR. HANNON: There is one final thing in our Symposium. We 
have been talking a lot about the maintenance of body temperature. 
Dr. Irving, from Arctic Health Research Laboratory, has brought 
out the term "peripheral heterothermy." Would you care to give us 
a few words, Dr. Irving? 
DR. IRVING: First, I want to express my thanks to Colonel 
Quashnock for the gracious manner in which he represented himself 
and the Air Command as our host, to Pat Hannon for his kindness in 
inviting me here for the extremely interesting program that has 
been presented, and to you, my friends and colleagues, I want to 
express my gratitude for having been introduced through your dis- 
cussions to subjects which were rather strange tome, for I usually 
look only at the periphery of animals. You have indicated some re- 
markable physiological complexities and some of the methods by 
which the warm-blooded animal system for communicating informa- 
tion is able to apply its very large capability for converting energy 
to the purpose of maintaining its individuality and specificity. 
I think that references to warm-blooded animals, as distinct 
from those that are cold-blooded, should emphasize the large order 
of the disposable conversion of energy that the warm-blooded ani- 
mals have in comparison with cold-blooded animals. I think we 
should also consider that from time to time, the central body tem- 
perature of the warm-blooded animals may rise three degrees or 
so, and that it regular ly falls half a degree or a degree during sleep. 
Schmidt- Nielsen's thirsty camels even elaborated this ability to 
modify the body's temperature to a cooling of some six degrees 
during the night time, making a total range of nine or ten degrees 
diumally in an undoubtedly homeothermous animal. 
Animals which are covered with fur and fat utilize their insu- 
lation. These materials are, however, inflexible insulators and 
animal producers of heat must utilize some variable insulator for 
the dissipation of heat. In cold climates this is effected by large 
variations in the temperature of the exposed extremities. 
One of the interesting examples of heterothermous tissues that 
John Krog and I observed was the foot of the seagull which, while 
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