Document Type



(1) In this study hibernator rodents were exposed to a warm environment and then a cold environment to determine whether cold acclimatization is necessary to permit a hibernator to go into dormancy. Four species were tested in September: hedgehogs, woodchucks, Glis dormice, and Eliomys dormice. With three species, (hedgehog, woodchuck, Eliomys dormice) if the rodents went into hibernation at all, they were capable of doing this within 24 to 48 hours after being removed from a warm environment. (2) Those individuals which hibernated directly after being placed in a cold environment, had not shown thermal ability in the warm environment. (3) One species (Glis dormice) seemed to require at least 10 days of cold preconditioning before it entered the state of hibernation. (4) We conclude that cold acclimatization is not necessarily required in preparation for the dormancy of mammalian hibernation. (5) With one specimen (woodchuck) which was monitored in detail, all initial hibernation occurred during the usual time of sleeping. (6) One specimen (woodchuck) was monitored all winter while hibernating in a free environment. During changes in the winter air temperature, the heart rates showed a precise inverse and homeostatic relationship with air temperature during hibernation, unrelated to awakening from hibernation. Therefore, hibernation in the free environment with a variable air temperature must be a more variable process than in the constant-temperature cold room.

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Journal Title

Proceedings of the Iowa Academy of Science





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©1970 Iowa Academy of Science, Inc.



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