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Bill Nye: Temperature Time Warp

Bill Nye: Temperature Time Warp

Author: Bill Nye

This tutorial by Bill Nye explains why cold-blooded creatures need a warm environment to survive.

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Temperature Time Warp


All mammals, animals like cats, dogs, squirrels and humans, are warm blooded. This means that our bodies make enough heat to keep our inside temperature the same all of the time, 37.0 degrees Celsius (98.6 degrees Fahrenheit). But most animals are not warm blooded. Fish, insects, snakes, and lizards are cold blooded. Their temperatures inside change with the temperature outside. On hot days, reptiles often let their bodies warm up, and on cold days, reptiles can’t help but cool off a bit. When it’s a cool day, a cold-blooded animal slows down. Try this:

What You Need:

1. a glass jar or plastic container with a cloth and a rubber band to cover the top 

2. an ordinary house fly

What You Do:

1. Catch a fly and get him or her in the jar. He or she must be alive. It may take a while. But don’t worry, if you’re patient, you can catch one. 
2. Put the cloth over the top. Try turning the jar upside down. 
3. Put your experiment in the refrigerator for half an hour. Don’t forget about it in there, since being in there too long could kill your fly. 
4. Take the jar out and watch your fly for a few minutes. Notice how fast it’s moving. 
5. Put your experiment in the sun for a few minutes, and check on your fly again. How fast is he or she moving now? 
7. Your fly has served you well. Let him or her go free.

What’s Happening?

When a cold-blooded creature gets cold, everything inside it slows down. So the fly moved slowly. The same is true for reptiles. After some time in the sun, the fly gets warmed up, and starts moving faster. That’s why snakes always lie around on rocks and roads, especially early in the morning — they get cold overnight, and they need to soak up some heat to get revved up again. Reptiles, insects, temperature, and motion – they’re hot topics that are quite cool!

Temperature Time Warp

Here's the same Home Demo in convenient PDF form!