The bleakness and chill of autumn evenings forewarns of the coming hostile winter season. Instinctively, a vast segment of the animal kingdom, unable to migrate to a more optimum biologic climate, prepares itself for survival. Through a variety of incredible methods, learned by each surviving species during millenniums of wintering experience, they prepare for their "winter sleep."
Almost every earthy aspect becomes a dormitory of sleeping creatures. The frozen earth appears barren and quiet though stocked with countless living forms. The life-and-death interspecies warfare of ordinary life temporarily ceases and natural foes slumber at close quarters beneath swamp mud, in the crevices of rocks, under the stiffened heaps of rotting vegetation and in dead wood. The carpenter ants burrow deeply into their microclimate chambers beneath tree bark and long tortuous tunnels deep in the earth become sleeping galleries for innumerable worms.
Larger and more highly developed members of the kingdom
Henderson AR. Induced Hypothermia is Not "Artificial Hibernation". JAMA. 1966;198(10):1074-1078. doi:10.1001/jama.1966.03110230090019