The Comparative Hypoxic Resistance of Hibernators and Nonhibernators

Abstract

A comparison has been made of the hypoxic resistance of 3 spp. of hibernators with that of 5 species of non-hibernators by subjecting them to a barometric pressure of 106 mm. Hg (pO2 of 21 mm. Hg) explosively produced. At this pressure the survival was considerably longer for the hibernators. The greatest survival was shown by the big brown bat, one of which lived more than 3 hours. Next in order was the ground squirrel and then the hamster. The shortest surviver was the English sparrow which lived only 21 sec. It is suggested that the ease with which a hibernator can be induced to go into the hibernating state parallels its hypoxic resistance. Much less respiratory distress is shown by the hibernators under hypoxic stress than by the non-hibernators under identical conditions. It is suggested that good hypoxic resistance is a prerequisite to ability to hibernate.