The Body of the Grasshopper
The body of the grasshopper, like that of other insects, has three sections—head, thorax, and abdomen. The head has two compound eyes, three simple eyes, and a pair of antennae. The antennae of short-horned grasshoppers point forward; those of long-horned grasshoppers generally curve backward over the body.Grasshoppers have two compound eyes, three simple eyes, and a pair of antennae.
Attached to the thorax are three pairs of legs. The hind legs are quite long and have thick, strongly muscled thighs that enable the grasshopper to jump a distance of roughly 20 times its own length. Some grasshopper species are wingless. Most, however, have four wings, attached to the thorax. They are folded lengthwise along the back when not in use. The hearing organs of the long-horned grasshopper are on its front legs, just below the knee. Those of the short-horned grasshopper are on the forward part of the abdomen, under the wings.
Male grasshoppers make crackling and buzzing sounds, usually in the daytime. Long-horned grasshoppers produce sounds by rubbing the front wings together. Short-horned grasshoppers “sing” by rubbing the hind legs against the front wings or by rubbing the wings together.
A grasshopper has its eyes, mouth, and antennae (an TEHN ee) on its head. It may look as if this insect has just two big eyes. But it really has five eyes.
A grasshopper’s two large eyes are compound eyes. They are made up of many separate lenses. The lenses work together to form a complete picture. A grasshopper uses its compound eyes to see. Scientists aren’t sure how a grasshopper uses its smaller eyes.
The thorax is the middle part of a grasshopper. The legs and wings are attached here. The abdomen is the back part. A grasshopper has breathing holes on its thorax and abdomen. These holes are called spiracles (SPY ruh kuhlz).
A grasshopper’s antennae are thin and very sensitive. They help the grasshopper feel its way around. That’s why antennae are often called feelers.
A grasshopper feels with its antennae. It smells with its antennae, too. As a grasshopper feels its way around, it picks up scents from the surroundings.
Scientists divide grasshoppers into two main groups. These groups are the short-horned grasshoppers and the long-horned grasshoppers. Short-horned grasshoppers have short antennae, and long-horned grasshoppers have long antennae. The antennae on a long-horned grasshopper are usually much longer than its body.
A grasshopper uses its legs and wings to move about. To walk, a grasshopper uses all six of its legs. To leap, it pushes off with its long, strong back legs. The grasshopper in the photograph is shown both before and during a leap. You can see how the grasshopper’s back legs propel it forward. Or, the grasshopper may shoot straight up into the air.
Many grasshoppers with wings can also fly. These grasshoppers use their back wings for flying. They use their wings in much the same way that a bird does.
Some grasshoppers have wings they can’t use. A few kinds never grow wings. These grasshoppers can’t fly. It’s a good thing they can leap so well!
A grasshopper needs to breathe air—just as a person does. But grasshoppers don’t have lungs. Instead, they have tiny holes, called spiracles, in their thoraxes and abdomens.
A grasshopper has 10 pairs of spiracles. Air goes into the insect’s body through the front holes. Air leaves the body through the back holes. Next time you see a grasshopper, look at it closely. You will see its abdomen move in and out as it breathes.
Short-horned grasshoppers feed on plants. Some eat only certain kinds of plants. Others eat any plant they can find. Many grasshoppers eat clover, corn, cotton, soybeans, and other farm crops. Hungry grasshoppers sometimes eat a whole field of corn stalks—right down to the ground.
Most long-horned grasshoppers eat plants, too. However, some eat the remains of dead animals. A few even eat other insects.
Grasshoppers are very big eaters. A large group, or swarm, of grasshoppers can eat up entire fields of grain. Their huge appetites cause farmers a lot of trouble.
You know that a grasshopper has very powerful hind legs. These legs are good for leaping. But short-horned grasshoppers also use their legs to make music!
Short-horned grasshoppers sing by rubbing a hind leg against a front wing. It’s a bit like playing a violin. The grasshopper’s hind leg acts as the bow.
Many long-horned grasshoppers can sing, too. But they use their two front wings instead of their legs. One wing has a “file.” The other wing has a “scraper.” The grasshopper rubs these two parts together to make a song.
Male grasshoppers usually do all the singing. The females rarely make sounds. Males have several reasons for singing. They sing mostly to attract females. Males also make sounds to warn other kinds of insects to stay away. Some grasshoppers even make alarm calls when danger is near.