Maybe it's the sound of birds calling. Maybe it's someone blasting Nirvana from a boombox. Or maybe--SCRITCH, SCRATCH, CREAK, BUZZZZZ--it's the sound of noisy insects.
In most parts of the United States, the air is filled with the calls of grasshoppers, cicadas (suh-KAY-duhz), crickets, and katydids from early summer to late fall. That's when the males go looking for mates. Their sounds are signals that say to the females, "Come mate with me!" (A few female katydids and grasshoppers answer back, but their sounds are harder to hear.)
Chances are, some of these noisy boys are chirping and trilling near you. Turn the page to see how they do it.
Imagine being buried alive for your whole childhood. That's what happens to most cicadas. Their moms lay eggs inside tree branches. When the eggs hatch, the larvas drop down and burrow underground. There they feed on tree-root juices.
When a cicada larva is full grown, it crawls out of the ground. Then it sheds its skin and becomes an adult. (See photo at right.)
Now it's time for the cicada to call for a mate. Here's how: On each side of the insect's body is a small patch of tight skin. (See drawing below.) Muscles inside the body quickly pull down on the skin patches and then let them pop back up, over and over again. The fast up-and-down movement makes a loud, chirping noise.
Only some kinds of grasshoppers can sing. So if you see a hopper nearby, check it out to see if it's one of the noisemakers.
Here's a male hopper now! (right) During the day, it climbs up a grass stem or a flower. Then it rubs the saw-like points on each back leg against a hard ridge on each wing. (See drawing below.) To you, it may sound like a rustling noise. But to a female hopper, it sounds like mating time.
Noise isn't the only trick that hoppers use to attract mates. Grasshoppers have great eyesight. So some male hoppers wow a female with their splashy colors. And some kinds do fancy dances to get her attention.
Katydids may sound a lot like their grasshopper cousins. But they make noises like their cricket relatives--by rubbing their wings together. (See drawing, next page.)
Rubbing wings may seem like a weird way to sing. But here's something even weirder--katydids, crickets, and some grasshoppers hear with ears on their legs! (See photo below.)
But making and hearing noise isn't as important to some katydids as others. Katydids don't call as often as most other noisy insect boys. Some tropical kinds rarely call or don't call at all.
A silent or almost-silent male uses another trick instead. He shakes his body in a special way. That lets any other katydids on his leaf or branch know, "Hey, there's another katydid here!"
You may find a field cricket (below) calling from a lawn during the day. Or you may see a tree cricket (left) perched on a branch, waiting for nighttime to make his calls. There are lots of other kinds of crickets too. You might even hear one chirping in your home!
Like the noisemaking katydids, almost all male crickets make loud chirps by rubbing their wings together. (The drawing shows how each wing scrapes across a bumpy ridge on the other wing.)
By squeak or by creak, noisy insects are out there trying to find each other. Hope you find them too!
RELATED ARTICLE: WHO'S MAKING ALL THAT RACKET?
There are thousands of different species (kinds) of "singing" insects. But chances are, only a couple dozen species live near you. With a lot of patience--and a little luck--you can find most kinds of your noisy neighbors.
Each species has its own song. Each "sings" at a different time of day or night. And each prefers a different kind of home. For example, cicadas usually sing from trees during the hottest part of the day (they're the really loud guys). And katydids and tree crickets usually sing from trees at night.
So here's how to find out who the noisemakers are. When you hear insect noises, go outside. Then pick out one noise and start inching toward it. As soon as you step close, the noise will probably stop. But if you stay still for a while, it usually will start up again.
Keep stepping and stopping, searching with your eyes and ears. (Try cupping your hands behind your ears.) When you find a noisemaker, sit down quietly nearby to watch it. Can you see how it's making those sounds? If you scoop it up in a net, you can get an even closer peek at what it looks like. (Just remember to let it go afterward.)
In the light of the moon, a male tree cricket has used his whistle-like sounds to attract a female. Now he's lifting his wings so she can slurp up a drop of goo on his back. That may help her make healthier eggs. Or it may keep her around so they can finish mating.
|Printer friendly Cite/link Email Feedback|
|Title Annotation:||mating calls of crickets, grasshoppers, katydids and cicadas|
|Date:||Sep 1, 1995|
|Previous Article:||Animal dances.|
|Next Article:||Meet my cool cousins.|