Grasshoppers, leaping insects of the order Orthoptera, include all
locusts. However, not all grasshoppers are locusts. The main difference
between the locusts and other grasshoppers is the length of their horns
(antennae). Locusts (Acrididae) have shorter antennae than other
grasshoppers (Tettigoniidae). The amazing leaps of grasshoppers are due
to long, slender hind legs with large thighs. These leaps are each many
times the grasshopper's body length. Most grasshoppers also have large,
straight, delicate hindwings, which enable flight. When a grasshopper is
at rest, these wings are folded up and protected by tough front wings
that cover them entirely. Grasshoppers are found in most areas of the
world except for northern Canada, Greenland, northern Asia, northwest
Africa,West Australia, and the Arctic and Antarctic regions. Long-horned
grasshoppers are herbivores and found wherever vegetation grows. Their
threadlike antennae are longer than their bodies. They are related to
katydids. When endangered, they spit out brown liquid called "tobacco
juice", and take huge, vigorous leaps to escape. The green color of
these grasshoppers conceals them in grass, where they eat pieces of
grass leaves and stems. Long-horned grasshoppers do not usually eat crop
plants. Short-horned grasshoppers, locusts, are called true
grasshoppers because they live only in grasses and leaves. They are well
known for traveling in huge swarms that lay bare whole farms or whole
regions of countries. The huge populations of swarms and the destruction
they have caused are mentioned in the Bible. Schistocera perigrina, a
North African locust, may have been the species described in the
biblical account of the plagues of Egypt.
Physical Characteristics of Grasshoppers
Grasshoppers are one to eight inches long when fully grown. Some
species undergo seasonal color changes, being green at some times and
red, olive, or brown at others. Like other insects, the grasshopper body
is divided into three parts: head; thorax, or mid-section; and abdomen,
or hindsection. A grasshopper's antennae, which have tactile functions,
are found on its head. Each grasshopper has a pair of compound eyes
with many lenses, located on the front of its head. Grasshoppers also
have three pairs of legs, extending from the thorax. The last pair is
much larger and longer than the others and enables jumping. Grasshoppers
eat leaves, roots, and stems of grasses, herbs, and shrubs, chewing
with strong mandibles (jaws), moving these jaws from side to side to
break apart their food. Most grasshoppers have two pairs of wings along
the back of the abdomen. Two hard forewings serve as protection and two
membranous hindwings are used to fly. When a grasshopper is not flying,
its hindwings fold up and are covered and protected by its forewings.
All long-horned grasshoppers "sing" by rubbing the bases of their
forewings together. Some male locusts make calls to females by rubbing
their hind legs against their wings, and others do so by rubbing their
hind legs or forewings against other parts of their bodies. The hearing
organs of long-horned grasshoppers are small growths just beneath the
knee joints of their front legs. In short-horned grasshoppers, these
ears are clear, circular areas on the abdomen at points just behind the
junction of hind legs and body. In females, growths shaped like sickles
are located at the rear of the abdomen. These ovipositors drill holes in
grass, twigs, or the ground, where eggs are deposited. Ovipositors of
short-horned grasshoppers are specially designed to deposit pouches of
eggs in the ground.
Grasshopper Life Cycles
In the spring,
grasshoppers hatch from eggs as pale, wingless nymphs (larvae). Then,
within ninety days, they develop into fullgrown locusts, molting four to
five times in the process. Mature insects mate, and about a week later,
females lay the eggs for the next generation. They die a few weeks
after this. Locusts, such as the Rocky Mountain locust (Melanoplus
spretus), lay their eggs in holes in the ground in the fall. The eggs
hatch in the spring, and young reach maturity in July or August. Those
of long-horned grasshoppers, such as meadow grasshoppers (Orchelimum
vulgare) are laid in low bushes or crevices in tree bark. Not only do
locusts eathuman crops, but in turn, humans have eaten them for
centuries. For example, Talmudic law exempts locusts and other
grasshoppers from the taboo on eating flying or creeping creatures
"going on all fours." Also, Shakespeare's play Othello mentions food
"luscious as locusts." Candied locusts are eaten throughout China and
the Philippines. In North Africa, locusts dried and ground into powder
are mixed into flour used to bake bread.
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