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The Complete Cricket Breeding Manual

Crickets Breeding Made Simple

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mosquito? A fly or a wasp? A cicada or a katydid? How can you tell without even looking? By listening! These insects may not be intentionally notifying you of their arrival, but their sounds are like fingerprints for the ear.

What is sound? For a long time, scientists considered sound to be only those vibrations that traveled through the air and activated our sense of hearing. But as they studied other animals such as dolphins, whales, and elephants, scientists became convinced that animals were sending and receiving signals through water, wood, and even the earth itself. So the definition of sound was expanded to include any vibration of air, liquids, or solids.

No matter who makes the vibration or what it is traveling through, sound moves in waves. These waves can be measured in several ways.The height of these waves is called the amplitude.The amplitude gives information about the volume of a sound. A large or high wave produces a louder sound than a small or short wave.

The measurement of the wavelength is called the frequency. Waves that are short from front to back (fast) are said to have a high frequency and a high pitch sound. The wavelength of A above middle C is about 2.6 feet (.8 m), while the wavelength of A below middle C is about 5.1 feet (1.5 m).

Sounds Abound

Infrasonic sounds are those that are too low for humans to hear. Elephants use their nasal passages to create low, rumbling, infrasonic sounds that can travel nearly seven miles. Ultrasonic sounds are those that are too high for humans to hear. They are often used in medicine for functions ranging from taking pictures of internal organs (ultrasounds) to smashing kidney stones. Supersonic sounds are those that deal with solid bodies that exceed the speed of sound, such as when a supersonic jet breaks the sound barrier and you hear a loud BOOM!

Wing WaVes

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It's late at night and both an Asian vampire moth and a female mosquito are in your room, looking for a meal of blood.Which one are you going to hear and have a chance to swat before you become dinner?

Materials

A wooden yardstick (meter stick) A table

Place the stick on the table with 2 inches (5 cm) hanging over the edge. Hold the remaining length of stick firmly on the table with one hand. Watch and

Journal Notes

listen to what happens as you push the thumb on your free hand down and off the hanging edge. Increase the part of the stick that hangs over the edge to 4 inches (10 cm) and repeat the experiment. Continue the activity increasing the part that hangs over the edge by 2 inches (5 cm) each time until you have only 2 inches (5 cm) remaining on the table.

As the hanging edge gets longer, does the sound get higher or lower?

Does the hanging piece move faster or slower?

Does the sound get louder or softer?

The 2-inch (5-cm) piece of stick doesn't have much length to move, making its wavelength short, giving it a high frequency and a high-pitched sound. The 34-inch (95 cm) piece has a greater length to travel, producing a longer, slower sound wave with a lower pitch. What this means is that a mosquito with a wingspan of around one-half inch (1.3 cm) produces a high-pitched whine, while you never hear the vampire moths that have wingspans several inches (or centimeters) wide.

Notable Insects

Depending upon the size of an insect, the size of its wings, how warm it is, and what it is trying to do, it will flap its wings at different speeds. If you were to listen to insects while playing the piano, you could match their sounds with these piano notes.

Crickets, katydids, and cicadas are definitely the stars of an insect orchestra, but that may be because of where they live— above ground and out in the open. Most of your hearing happens when vibrations in the air reach your eardrums. Insects living inside wood or underwater could be singing a symphony, and you would never know it.

Do You Hear What I Hear?

Just under the bark of a dead or dying tree, adult click beetles, stag beetle larvae, and termites all stake out a dinner claim as they gnaw through the decaying wood. After the sounds of their chewing alert a woodpecker to their location, they may beat their heads against the walls of their tunnels and nests to warn others of the approaching attack. Listen carefully as you gently scratch the top of a wooden table. Lay one ear on the table and scratch again. Notice any difference? Can you hear anything if you put your ear against a dead tree?

When you make a sound through air vibrations, the air scatters the sound in all direc-tions.When you direct your sound efforts through a solid, such as wood, the vibrations are more contained, and therefore are stronger (or louder). So an

Measuring Sounds

Two common words used when scientists are talking about sounds are hertz and decibels. Hertz (abbreviated Hz) is the measurement of the frequency, or how many sound waves pass a given point in one second. One kilohertz (kHz) is 1,000 cycles per second; 1 megahertz (MHz) is 1 million cycles per second. Humans can hear sound frequencies from about 20 Hz to about 20 kHz. You don't hear your own heartbeat because it beats too slowly, and you can't hear a high-pitched dog whistle because it produces a sound at 30 kHz or more.

Decibels are the measurement of sound energy and intensity, which is related to loudness. Zero (0) is the softest sound that humans can hear. Sounds louder than 85 decibels can cause hearing damage if you are exposed to them for too long.

As an example of the difference between the two terms, think of a cicada. Male cicadas produce a song that creates a sound wave measuring 390 Hz, which is about the same pitch you hear for the word "star" when you sing Twinkle, Twinkle, Little Star (G above middle C on the piano). Their song is one of the loudest noises made by an animal, registering up to 112 decibels, which is about the same loudness as a rock concert or leaf blower.

Common Insects Measured Sound Wave Rates

(c/s = cycles per second) Closest Piano Note Equivalents

Butterfly

Dragonfly

40 c/s the third E below middle C

Bumblebee

117 c/s the second A

below middle C

Tired Bee

326 c/s

E above middle C

Housefly

345 c/s

F above middle C

Active Bee

435 c/s

A above middle C

Mosquito

587 c/s D one octave above middle C above middle C

No-see-um midge

1050 c/s C two octaves animal communicating through wood has to use less effort than one that is communicating through air.

Water Words

When you are near water, frogs and ducks might make so much noise that you can't hear anything else. But if you watch and listen carefully, you might witness aquatic insects using their own water words.To attract a mate, the male backswimmer makes a very loud noise by rubbing his front legs together or against his beak.You can hear him 130 feet (40 m) away under water. Whirligig beetles are like bats. They use echolocation to find their food.The beetles feed on insects that fall into the water, detecting them by the ripples they make.

Insect Ears

You may know that some insects use their antennae to sense sound, but have you ever looked for an insect's ears? What do

Night Life

During the quiet hours of late night, it is much easier to hear sounds that are usually missed during the day. Night is also a time of hidden insect activity. Years ago, as people would sit up at night with a sick relative or friend, they would sometimes hear a tap-tap-tap sound coming from within the walls of the house. Since medicine and doctors were hard to come by, many times the sick person died. People started to believe that when they heard tapping noises at night, someone was about to die. When they discovered that the sound was made by a wood-eating beetle living in the timbers of their house, banging its head on its tunnels to attract a mate, they named the insect "the death-watch beetle."

These scanning electron micrographs produce highly magnified views of a katydid's leg, showing its ear. Anna Price, Department of Biology, Wake Forest University insects' ears look like, and where are they located? Most insects' ears are simply a thin membrane called a tymbal, stretched over a very small hole, so they look like the top of a drum. But you won't see an insect's ears on the side of its head.You would need to use a powerful magnifier and look on a green lacewing's wings, on the inside of a katydid's or cricket's knees, or on the side of a short-horned grasshopper's body at the base of its abdomen!

Here's to Jars t At

1/1 / hen a tiger moth hears 1/ 1/ the high-pitched clicks of a bat headed its way, it responds by dropping like a stone while making clicks of its own, trying to jam the bat's radar.

Materials

Scissors 1 large balloon Short stiff tube, such as a plastic soda bottle with both ends cut off Rubber bands

Rice or cereal, several grains

Cut the balloon in half around the circumference, then stretch a piece over each end of the tube and secure the pieces with rubber bands. Hold the tube upright and place a few grains of rice or cereal on top. Gently tap the lower balloon membrane and watch what happens.

Journal Notes

When I tap the lower balloon membrane, this is what happens:

When I tap the lower balloon membrane, this is what happens:

When you tap the balloon, you are making it vibrate. The vibrations are transferred to the air inside the tube, and then to the balloon on top, making it vibrate and the grains jump.

■ hildren in Africa sometimes I catch the giant Goliath bee-V_\ tie, tie one end of string to one of its legs, and the other end to a stick. Then, as the beetle flies overhead in a circle, it makes a loud buzzing noise.You can make a vibration sensation by creating your own buzzing bug.

Materials

1 18-inch (45-cm) piece of string Popsicle/craft stick Scissors Stiff paper Markers Glue Stapler

1 1-inch (2.5-cm) diameter foam ball Wide rubber band

Tie one end of the string around one end of the craft stick. Cut the piece of paper so that one edge is straight and slightly smaller than the Popsicle stick. Draw a flying insect on both sides of the paper. Glue the straight edge of the paper to the middle of the stick, covering the string. Staple the paper and the string to the stick. Cut the foam ball in half. Dab glue on each flat side. Place one half on each end of the stick. Stretch the rubber band around the stick and craft ball ends.After the glue dries, go outside and swing the buzzer over your head.

Some insects use body parts other than wings to make sounds.To mimic the chirp of crickets, grasshoppers, and katydids rubbing their legs or wings together, rub a stick across the

Bees Buzz Around the World

While many English-speaking people say that bees buzz, other languages have other words for it. In Spain, bees are said to zumbar, in Germany they summen, in Israel they zimzum, and they brzecza in Poland.

teeth of a comb. Press on a baby food jar lid to copy a cicada clicking its abdomen. To sound like the vibrating spiracles of the Madagascar hissing cockroach, stretch the neck of an inflated balloon apart as you slowly let the air escape.

the button in and out

Journal Notes

What is making the sound? How can I change the sound? The foam ball pieces hold the rubber band away from the craft stick, giving it room to vibrate as it moves through the air. Your swinging speed plus the width and length of the rubber band affect how quickly it can vibrate, which determines the sound it makes.

]ngect_Amplifier c

1 ome insects are very hard to \ hear.An amplifier is some-vJthing that makes a sound louder. Use this simple amplifier to help you hear the sound an insect makes.

Materials

Sound-producing insect 1 paper cup

Piece of waxed paper large enough to cover top of cup Rubber band Timer

Catch an insect that makes an audible sound. (Don't select a stinging insect for this experiment.) Carefully transfer the insect to a paper cup. Place the waxed paper over the mouth of the cup, then use the rubber band to keep it in place. Put the cup up to your ear and listen.To slow down an insect and change its sound, put the cup, with the insect in it, into a refrigerator for up to 10 minutes. But don't forget to take it out! Set the timer for 10 minutes to help you remember. After you're finished listening, be sure to set your singer free.

Sometimes, it is better not to be heard.When male crickets are chirping trying to attract a mate, their calls can also attract tachinid flies.These flies are parasites. They lay their eggs inside the cricket.When the larvae hatch out of the eggs inside of the cricket, the cricket dies.

You might be surprised by how loud an insect can sound.

Dig This

Journal Notes

Another simple amplifier is a cone shape (such as a megaphone). Cones amplify by directing sound waves toward their targets, rather than letting them scatter in all direc-

burrow in the shape of a double megaphone. Then he sits behind it and "sings" his song. The double megaphone is so effective that a person can hear his song from almost a

This is the kind of insect I put in the cup:_

The insect sounded like this:

tions. The male mole cricket digs his quarter mile away.

This is the kind of insect I put in the cup:_

The insect sounded like this:

After I chilled the insect in the cup, this is what it sounded like:

This works on the same principle as the model ear, only this time the insect makes the air in the enclosed chamber vibrate, which in turn makes the waxed paper vibrate. By containing these vibrations to a small space, the effect of the vibrations is increased, or amplified. You can use the cup without the waxed paper to amplify the insect sounds coming from a dead tree. Place the open end of the cup against the tree and your ear on the bottom of the cup.

Sound Off gentry

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