Did you ever wonder why we sleep only one night at a time yet bears sleep for five months? Discover the answers by watching this Serious Science video and reading the information below. And to take this learning adventure into your classroom, have your teacher download the free Lesson Activity at the bottom of this page so everyone can share in the fun of this inquiry based learning.


Our bodies actually lapse into an altered state of consciousness. We’re not conscious or unconscious. It’s kind of in between. Our breathing (respiration), heart rate, and metabolism all slow down during sleep so we don’t burn as many calories. Our brains dial down to about half their normal activity and recharge through the process of dreaming.

Many other organisms need much more than just daily rest and sleep to survive. They need an intense resting survival strategy called… torpor. Torpor is where an animal goes through a change where it has a significant reduction in its metabolism and calorie needs. And that’s usually timed to periods when there isn’t any food available – such as during the winter. Metabolism is the combination of body functions like physical movement, brain activity, breathing, heart rate, and burning calories to maintain body temperature. If some animals didn’t use the altered state of torpor to reduce the amount of calories their bodies needed for normal activity, they might not survive. Ta-da, but torpor to the rescue! Read on below in the Learn More, or better yet, sit back, relax and watch this Serious Science video. Just don’t get too relaxed and fall into a state of torpor. Duah.


Plus, the educational partner noted below supported the video and lesson content here for all of us to learn from. They also offer other learning opportunities on their website. So click on their logo to discover more!

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