Scientists say that "true" hibernators, such as ground squirrels, practically die during hibernation. Their body temperature drops to near freezing, and their organs shut down. A ground squirrel's heart rate, for example, slows from a few hundred beats per minute to just five. Even the little nut lover's bones and teeth deteriorate, as every tissue toes the line between life and death. They do wake up every few weeks. But normally, you can poke, prod, or even eat a hibernating critter and get no response.