Facts & Trivia

Cricket Thermometer

The current temperature can be estimated by using one of several commonly known mathematical calculations involving counting the number of times a cricket chirps over a period of time and then applying that number to an equation.  Male crickets "sing", or chirp (usually at night when it's cooler) to attract female crickets and to "scare" other males away from their territory.  The chirping sound is made by the male cricket rubbing together little teeth on it's wings.  This causes a vibration at a certain frequency, resulting in a sound wave called stridulation.  Stridulation is derived from the Latin word stridulus, which means "squeaky." 

Being cold-blooded, the cricket's metabolism is proportionally affected by the ambient temperature.  When the temperature rises, so does the frequency of the cricket's chirp.  There are several variations of the cricket temperature formula that are based on Dolbear's Law formulated in approximately 1896.  A. E. Dolbear (1837-1910) was a physics professor at Tufts College. He also served as a mayor of Bethany, West Virginia.

Although other chirping insects could be used as "thermometers", it has been said that Dolbear's crickets are the most accurate temperature indicating insects.  Presumably, all variations of the cricket thermometer formulas derive from the same scientific rules of physics, mathematics, and physiology used in Dolbear's Law.  Experiment with these equations to determine which works best in your neck of the woods.

Count the number of chirps in this amount of time	and apply this calculation to get the temperature in degrees Fahrenheit.
24 Seconds	Add 35
15 Seconds	Add 40
60 Seconds	Subtract 40, Divide by 4, Add 50
15 Seconds	Add 37

 
(This page was last modified: Wednesday, November 03, 2004)