18 August 2023
On summer nights male crickets chirp to attract a mate. Each species has a distinctive call meant to lure the proper females. If you know bug sounds you can identify the chirping species.
One of the most common is the snowy tree cricket (Oecanthus fultoni) which occurs in most of the U.S. Unless you live outside their range you’ve probably heard this nighttime sound.
Because they are ectotherms, crickets chirp faster in heat and slower in cool weather. You can even use Dolbear’s law(*) to calculate the ambient temperature based on the snowy tree crickets’ chirp rate.
So the sound changes. But does this heat-related change in tune mean the females no longer recognize the males? Nope. The heat changes the sound and it changes the crickets’ ears so that they hear the same old tune. Read more in this vintage article:
(*) p.s. The name of Dolbear’s law has an interesting backstory.
Amos Dolbear published The Cricket as a Thermometer in 1897 in which he described how to calculate the temperature based on the snowy tree crickets’ chirp rate. However, according to Wikipedia, Margarette W Brooks had already published the formula in 1881. She did not get the fame and it took some sleuthing to discover her. He got the fame and the name because, at the time, Science listened only to men. 140 years later women have a greater voice but the playing field is still uneven.
(photo and video credits are in the captions)