Folklore widely claims that you can tell the temperature simply by listening to how fast crickets ‘sing.’ Is that really true?
Read on and I’ll share the truth by the end of this column. But first, let’s learn something about these little guys and their buddies.
Crickets are related to grasshoppers and resemble them a little, with their long hind legs, hidden wings and predilection to jump when threatened.
But that’s where the similarities end.
Grasshoppers sport antennae, have mostly cryptic colouration and produce a ‘song’ by rubbing their hind legs against their wings. Known as stridulation, singing in crickets is produced by their rubbing their wings together.
Grasshoppers have pseudo-ears on the base of their abdomen, while crickets have ‘ears’ on their feet!
Mostly diurnal, grasshoppers are readily seen in the daytime as they feed on various grasses, while the crepuscular (i.e. dusk/dawn) cricket comes out in the evening and early morning and eats plant and animal matter.
Known collectively as orthoptera (Greek for rigid-winged), over 18,000 species are known worldwide. But only a handful occur in North America – 150 crickets (including the mole, field, bush, scaly, ant, ground, tree and swordtail families), plus 630 grasshoppers (including locusts and hoppers).
Just to keep this interesting, throw in another ally – the katydid, a critter sort of halfway between the grasshopper and cricket – and you have quite a mix!
Locusts, of course, have biblical fame, but are also known to have caused billions of dollars in damage on all continents except Antarctica. When they swarm, they can literally blacken the sky and devastate the landscape, eating everything in sight.
Crickets, grasshoppers and katydids all undergo incomplete metamorphosis as they develop. This simply means they hatch as an egg, slowly grow and look like a tiny adult when small, eventually growing to full size. There is no larval (e.g. caterpillar) stage in their life cycle.
Grasshoppers existed long before dinosaurs, having been around for over 200 million years.
Modern grasshoppers will spit when annoyed so beware!
While only male crickets and grasshoppers generally chirp, females can sing as well, but only softly.
Crickets are eaten, reviled and revered around the world. Many cultures hold them in high esteem, while others see them as a pest or food.
In Brazil, crickets singing are said to foreshadow rain, while in Barbados, a cricket in your home apparently means money will be coming to the owner. The Chinese believe so strongly in the good things that happen when crickets live with them that they keep them in cages as pets, hoping their chirps will bring good fortune.
And apparently as long as it hovers between 55F and 100F (13C and 38C), crickets can tell the temperature. They’re cold-blooded and their muscles react more readily as the temperature increases. The singing is produced by using these muscles. So as the temperature rises, so does the ease to trigger the muscles to work.
But it gets complicated as the species of cricket, its age and sex affect their accuracy. Some species such as the sow cricket (reputed to be the most accurate) can come within one or two degrees Fahrenheit of the actual temperature.
Here’s how to calculate this for yourself: find a sunny spot where crickets are singing and start counting the number of chirps a single cricket makes in 14 seconds. Repeat this a few times and take the average. Now add 40 to the number and you have the temperature in Fahrenheit.
Insects are an interesting and complex group and never cease to amaze me with how different, versatile and clever they can be.
So next time you see a cricket, don’t chase it away. Just admire it – and pay heed to the temperature, dressing accordingly!
Geoff Carpentier is a published author, expedition guide and environmental consultant. Visit Geoff online at www.avocetnatureservices.com, on LinkedIn and on Facebook.