Final answer:
Hibernation is a state of inactivity and metabolic depression in animals during the cold season, enabling them to conserve energy by using stored body fat.
Step-by-step explanation:
Hibernation in Animals
The behavior described in the question, where an animal becomes inactive and uses its body's fat for energy during the cold season, is called hibernation. During hibernation, an animal's body processes slow down, and its body temperature drops, allowing it to conserve energy when food is scarce. This state of torpor can last several weeks to months. Animals like bats, squirrels, and snakes are known to hibernate. Contrary to popular belief, bears enter a deep sleep but do not experience the same levels of reduced bodily functions as true hibernators.
It is important to differentiate hibernation from migration, which is the movement of animals from one location to another typically in search of food or better environmental conditions. Also, it is distinct from imprinting and conditioning, which are forms of learning.