During the past two decades there have been numerous reports concerning the effects of altitude, or hypoxic stress upon the reproduction, growth and metabolism of mammals and of man. The pertinent literature has been exhaustively reviewed by Stickney and Van Liere ( 'El), by Van Liere ( '42), by Moore and Price ( '48) and by Monge ( '48). survey of this work discloses that it has involved almost exclusively the reaction to, and adaptation to acute, severe stress on the part of the individual organism. The primary exception has been the series of observations by Monge with reference to the long-term behavior of man and animals in the Andes. Within recent years, furthermore, it has heen noteworthy that many investigations have utilized the method of intermittent exposure to relatively high simulated altitudes in decornpression chambers.
Several years ago it became evident that one type of exposure to altitude stress was being neglected, at least from the direct experimental as opposed to the historical point of view. This aspect of the problem consists of the sojourn of organisms, continuously rather than intermittently, at those moderate altitudes between 10,000 and 18,000 feet at which domestic animals and humans are likely to find a reasonably permanent habitat. Such a sojourn, furthermore, is envisaged ' Tho cost of this investigation was met in part through contracts N7-onr-29504 and N7-onr-29538 between the Office of Naval Research axid the Regents of the University of California.