Summary
Reduced metabolism and body temperature allow animals to survive scarce winter food.
In depth
Body temperature and metabolic rate drop sharply; hibernating bears reduce heart rate but remain relatively warm, while ground squirrels cool near 0 °C. Brown fat and stored fat provide energy. Daily torpor occurs in hummingbirds and bats.
Torpor reduces energy needs. Arousal costs energy. Hibernators may be periodically aroused.
Remember: bears are light hibernators with moderate temperature drop.
Torpor is a short-term reduction of metabolism, used daily by hummingbirds and small bats, saving large amounts of energy. Hibernation is seasonal and prolonged, as in ground squirrels where body temperature falls to near 0 degrees and heart rate from about 200 to 5 beats per minute, with periodic arousals every one to three weeks that use much of the energy. Bears do not enter deep torpor but reduce metabolism by about 75 percent and survive months without eating, drinking or urinating, recycling urea.
Preparation includes hyperphagia and fat accumulation. Hibernators resist muscle loss and tissue damage, and research seeks to apply lessons to medicine and space travel. Aestivation is a summer equivalent in desert animals and lungfish. Climate change can disturb timing.
Key idea: hibernation is controlled and reversible, and is not just sleep.
Frequently asked questions
What is Hibernation and Torpor?
Reduced metabolism and body temperature allow animals to survive scarce winter food.
Which area of biology covers Hibernation and Torpor, and how advanced is it?
Hibernation and Torpor is one of the 53 topics in Zoology & Animal Diversity. It is rated Intermediate, so it suits learners who already know the core vocabulary. Related topics in this area include Metabolic Scaling, Thermoregulation in Animals, Animal Locomotion.
Can you give an example of Hibernation and Torpor?
Some bears can give birth while hibernating.
What should I learn before Hibernation and Torpor?
Work through the Beginner topics in Zoology & Animal Diversity first, such as Animal Kingdom, Vertebrates and Invertebrates, Sponges, then return to Hibernation and Torpor. Intermediate topics assume the Beginner vocabulary.
What topics are related to Hibernation and Torpor?
The closest topics to Hibernation and Torpor are Metabolic Scaling, Thermoregulation in Animals, Animal Locomotion, Animal Migration. Comparing them side by side is a good way to see how the ideas connect.
How can I check that I understand Hibernation and Torpor?
Read the summary and the in-depth section, then use the quick check on the interactive lesson for Hibernation and Torpor. To practise the whole of Zoology & Animal Diversity, use the Zoology & Animal Diversity quiz.
How is Hibernation and Torpor different from Metabolic Scaling?
Hibernation and Torpor: Reduced metabolism and body temperature allow animals to survive scarce winter food. Metabolic Scaling: Metabolic rate scales with body mass to the three-quarter power, described by Kleiber's law. Read both side by side and note what each one explains.
How should I study Hibernation and Torpor step by step?
First, read the summary and write the definition in your own words. Second, read the in-depth section and note any example. Third, compare it with Metabolic Scaling and explain the difference aloud. Finally, take the Zoology & Animal Diversity quiz and come back to this page for any question you miss.