Laurence Irving

Heat regulation in some arctic and tropical mammals and birds.

A series of arctic and tropical mammals and birds at Point Barrow, Alaska (lat. 71° N.) and in Panama (lat. 9° N.) was subjected to various air temperatures in a respiration chamber where the heat production was determined by oxygen consumption or carbon dioxide production. The larger arctic mammals and birds showed no increase in metabolism at — 30° C. and from observations on sleeping animals it is probable that their zone of thermoneutrality extends to — 40° C. or — 50° C. The smaller arctic species show a high critical temperature and the tropical species even higher. Metabolic heat production increases rapidly with lowering of the temperature in a tropical mammal or bird, and slowly in an arctic animal. It can be shown theoretically that in a thermoregulated system with a fixed basal energy level and variable insulation the critical gradient is proportional to the maximal insulation and the basal energy level.In a large series of experiments including our tropical and arctic animals, and all animals ...

Measurement of some physiological reactions to Arctic conditions.

Wars arise when people conflict a t geographical frontiers, and out of these impacts a confusion of opinion develops which impels people, in ignorance, to resort to arms and prevents them from gaining, through knowledge, the advantages of working and thinking for the common interest of the world. Science is now universally recognized as a significant factor in the welfare of nations, and it became important to determine how physiology could most help to throw the light of reason upon world affairs. It seemed certain that a great contribution could be made in the determination of the physiological reactions to difficult conditions, whether these be geographical, climatic, or social or those arising through the new orders of power and speed which are a t hand. It appeared likely that one group of physiologists would deal with both geographic and climatic stressesaffectinglife, and, after conferences and discussions, in which the National Research Council and the Research and Development Board gave their interested and critical attention, it was decided to go ahead on a program of research called “expeditionary physiology. ” Simultaneously, a strong interest in biological research under natural conditions was developing among another group of biologists, who were primarily concerned with behavioral aspects of animal societies, and it was agreed, in organizing means for these two different methods of research in the field, that the near identity of motives confirmed their value and the correctness of the approach. Since then, the writer has watched with interest the development of the Committee for the Study of Animal Societies under Natural Conditions, the progress of its members’ field studieç, and the establishment of its remarkable institution at Jackson Hole. The purpose of this paper is to account briefly for the progress which has been made in expeditionary physiology. My concern with broader aspects of organization has recently been latent because of my connection with a research project in expeditionary physiology, under the sponsorship of the Office of Naval Research, which has led me, with a group of about fifteen scientists, into concurrent field studies in problems of tropical, desert, and Arctic physiology. The emphasis has been strongest upon Arctic problems, because the Navy is conducting an intensive exploration for petroleum on the Arctic Slope of Alaska, which is that great area north of the Brooks Range, extending to the Arctic Sea. The field center of this activity is Point Bar,row, Alaska, and the broad outlook of the Navy, expressed through the Director of Petroleum Reserves, Commodore W. R. Greenman, haç açsociated with the exploration for petroleum the assistance of a number of important scientific and technical activities. Some of these are the U. S. Geological Çurvey, U. S. Coast and Geodetic Survey, Arctic Test Station, Civil Aeronautics Authority, U.