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Crickets as Temperature Gauges

Did you know crickets can tell you the temperature outside? Yep, it’s true! It’s known as Dolbear’s Law, and was discovered in the late 1800’s. There’s even a full-on formula that goes with it; nerdy folk can check Wikipedia for more on that.

You may have noticed that cricket chirps slow as fall approaches and the weather cools. Because they are cold-blooded and can’t make their own body heat, their muscles contract at different rates depending on how warm or cold it is outside. When the temperature drops, their muscles get colder and stiffer (much like ours do), and they simply can’t move as quickly as they do when it’s warmer.

So how do we find out the temperature from a cricket? Easy, with a little bit of math! First, count the number of chirps from a single cricket in 15 seconds. Next, add 40 to whatever number of chirps you heard, and that is the approximate outside temperature in degrees Fahrenheit. To figure the approximate temperature in Celsius, count the number of chirps in 8 seconds and add 5. Cool, huh?

Although not precise, it’s fairly accurate and useful if you’re out camping or in a survival setting. Just remember, crickets don’t chirp once it drops below 50*F because it’s too cold to use their muscles, which is a good warning to us to find shelter and get warm. This little trick could save you from hypothermia, or at the very least, amuse your buddies around the campfire!