Since the time of Spallanzani and John Hunter, the phenomenon of hibernation has intrigued scientists. Spallanzani showed that hibernating animals can live for a time in an atmosphere of carbon dioxide gas. Hunter investigated digestion during hibernation; he forced bits of worms and pieces of meat down the throats of hibernating lizards and later recovered the food unaltered.
Subsequently, some of the experimental procedures have become more elegant, and the seeking of answers more imperative. Fields of study as diverse as "sleep," fat metabolism, and space medicine share a common interest in hibernation. Now, in a recently published book,1 several investigators describe the current status of the fascinating subject, mammalian hibernation.
A particularly striking observation, confirmed by several investigators studying different aspects of hibernation, was the remarkably rapid alteration of body functions as hibernation ends. In the hamster, for example, lipogenesis is blocked during hibernation, but, as that state