It is possible to estimate the temperature by counting how often a cricket chirps. This equation was originally developed in 1897 by Amos Dolbear and is now known as Dolbear's equation.
A practical version of the equation involves counting the number of chirps in 15 seconds and adding 37 to the total to get the temperature in degrees Fahrenheit. There are different versions depending on the exact species of cricket.
Dolbear did not specify which species he studied, but it is now believed to have been the snowy tree cricket. However, the practical formula will still work for field crickets with only a small margin of error.
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