Did you know that the common shrew survives the winter months by shrinking? The little mammal cannot store enough fat in order to hibernate and loses body mass to conserve the energy it needs to survive the cold.

Now scientists have found that the skull and brain of Sorex araneus also deteriorate as winter approaches. The shrew’s cranial bone and brain matter somehow break down and get reabsorbed into the body only to rebuild as the earth warms — and the shrew can burrow and scurry and nibble on earthworms again.

“Maybe the shrews get a little dimmer during the winter — and that’s the price of not starving to death,” mused one ecologist in Scientific American. The shrew was not available for comment. It was vulnerable in its burrow and capable of getting to spring. It slept. Its heart beat only a little fewer than 700 beats per minute. It dreamed of trail-making in the loosening ground. It dreamed of the green world returning.