To prepare for the winter, humans usually bundle up, drink hot liquids and light the fireplace.
But tiny shrews have a rather unusual method of surviving low temperatures.
Scientists captured shrews in Germany and observed their body differences during different times throughout the year.
The researchers discovered shrews' brain casings and brains shrunk and then regrew by the summer.
Javier Lázaro, a Ph.D. student, told Newsweek: "We are dealing with a system that loses in this case bone tissues, and in some still unknown mechanism, they are able to regenerate this tissue.”