Grasshopper


Grasshopper is a Leaping Insect which is similar to Cricket in appearance. A Grasshopper does not actually Jump rather they use their Legs as a Catapult. Grasshoppers can both Leap and Fly. A Grasshopper about 1 inch (2.5 centimetres) long can leap 20 inches (50.8 centimetres).  Grasshoppers are Cold Blooded Animals and need to warm up before they can start their daily activities. There are hundreds of unclassified Species of Grasshoppers, distributed throughout the temperate and warmer regions of the world. There are about 18,000 different species of Grasshoppers.

Life Cycle of Grasshoppers Grasshopper Life Cycle

Egg - The life cycle of Grasshoppers starts from the egg stage. By mid-summer, the Female Grasshoppers lays the fertilized eggs in the form of Egg Pods, usually more than ten, either in the sand or among leaf litters. Each Egg Pod consists of about 10-300 eggs that are rice shaped. The eggs remain dormant in autumn and winter seasons, for almost ten months. By spring or early summer, the eggs hatch into Nymphs (offspring).

Nymph - Immediately after hatching, the young Nymphs start feeding on soft and succulent plant foliages. Nymphs are miniature versions of Adult Grasshoppers, except that they are light in colour and do not possess Wings. Nymphs undergo 5-6 moults and change their form and structure, before becoming adults. This Moulting process is known as 'Incomplete Metamorphosis'. The Nymphal Stage may last for a period of 5-10 days, based on the Species and the weather condition, especially temperature and humidity. As the Nymphs moult, their size increases and wing pads progressively develop on the Thorax portion of the body.

Adult - After 25-30 days, the Wings are developed completely and the Nymphs mature into adults. By the time, an egg matures into an adult, the Grasshopper is about eleven months old.

The life span of Grasshoppers is about 12 months. Studies have found out that the survival rate of Nymphs after hatching is about 50 percent, as chances are high that they may be eaten by predators like birds, rodents and lizards. This way, Grasshoppers play a major role in the effective functioning of an ecosystem, by providing food for many predators in the food chain. A Swarm of Grasshoppers, also known as Locusts, might cause severe damages to the crops, affecting the crop yield.

There are Two Types of Grasshoppers:

1.  Long-Horned Grasshoppers - Long-Horned Grasshoppers have Antennae, or 'Feelers', about the same length as the body.

2.  Short-Horned Grasshoppers - Short-Horned Grasshoppers have Antennae less than half the length of the body. Short-Horned Grasshoppers are often called Locusts, particularly when they migrate.

Short-Horned Grasshoppers are the one's which cause huge crop damage when they migrate in huge swarms in search of food, devouring virtually every green plant in their path. Long-Horned Grasshoppers do comparatively little damage.

Scientific Classification

Kingdom - Animalia.
Phylum - Arthropoda.
Subphylum - Hexapoda.
Class - Insecta.
Order - Orthoptera.
Suborder - Caelifera.

Physical Features


Colour -  Grasshoppers are generally coloured green, brown, or gray.

Weight - Weight varies from Species to Species but an average sized adult weighs up to 300mg.

Size - They range in length from one-half inch (1.3 cm) to more than six inches (15 cm) in some tropical species.

  • Female Grasshoppers are larger than the Males.

A Grasshopper has Three Section such as Head, Thorax and Abdomen.

1)  Grasshoppers Head - A Grasshopper has its Eyes, Mouth and Antennae on its Head.

The Mouth Parts are attached to The Ventral Side (underside) of the head portion and surrounds the mouth or the oral cavity which faces down. Their mouth parts are specially designed for chewing with jaws that move back and forth rather than up and down. The Mouth also contains Organs which are used for Tasting.

The different Mouth Parts are:

Labrum or the Upper Lip - It is a broad, roughly rectangular shaped structure. It is used  to hold the food between the Mandibles and the Maxillae.

Lingua or the Hypopharynx - A membranous tongue-like structure found attached beneath the Labrum.

Mandibles - A pair of hard, horny, heavy, large, with jagged inner edges and dark coloured triangular structures found one on either side. The two Mandibles move in horizontal motion and crush food between them.

Maxillae - A pair of structures lying outside and behind the Mandibles. Each of them consist of 5-segmented sensory maxillary Palp in addition to other parts. The Maxillae are used to manipulate the food before it enters the mouth.

Labium - It forms the broad median lower lip consisting of several parts in addition to a pair of 3-segmented Labial Palps on either side. Labial Palps have sense organs which help Grasshoppers to chose a suitable vegetation. Labium helps to hold the food between the Mandibles and the Maxillae.

Grasshoppers have Five Eyes. Its 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. It is not clear as to how a Grasshopper uses it's Three Simple Eyes. Its sense of vision is in the Compound Eyes, while change in light intensity is perceived in the Simple Eyes or Ocelli.

There are Two Antenna's attached to the Head. The Antennae of Short-Horned Grasshoppers point forward; those of Long-Horned Grasshoppers generally curve backward over the body.

2)  Grasshoppers Thorax - The Thorax is the middle part of a Grasshopper.

The Legs and Wings are attached here. There are Three Pairs of Legs attached to the Thorax. 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. and they can reach a speed of 8 miles per hour when Flying

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. They can reach a speed of 8 miles per hour when Flying.

Grasshoppers also have breathing holes on its Thorax. These holes are called Spiracles. 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.

3)  Grasshoppers Abdomen - The Abdomen, consists of 11 segments. The First Segment is firmly fused with the Metathorax and contains the auditory organ with its Eardrum Cover, the Tympanum.

Female Grasshoppers have triangle shaped sharp points at the end of their Abdomen that are there to help them lay eggs underground.

Males have a single unpaired plate at the end of the abdomen. The terminal segments of the abdomen are reduced and modified to bear the external reproductive organs, the genitalia, and the associated structures.  

  • The Grasshopper hears by means of a Tympanal Organ situated either at the base of the Abdomen (Acrididae) or at the base of each Front Tibia (Tettigoniidae).
  • Grasshoppers have open Circulatory Systems, with most of the Body Fluid (haemolymph) filling body cavities and appendages. The one closed organ, The Dorsal Vessel, extends from the head through the Thorax to the Hind End. It is a continuous tube with two regions: the Heart, which is restricted to the Abdomen; and the Aorta, which extends from the Heart to the head through the Thorax. Haemolymph is pumped forward from The Hind End and the sides of the body through a series of valved chambers, each of which contains a pair of lateral openings (ostia). The Haemolymph continues to the Aorta and is discharged through the front of the head. Accessory pumps carry Haemolymph through the Wing Veins and along the Legs and Antennae before it flows back to the Abdomen. This Haemolymph circulates nutrients through the body and carries metabolic wastes to the Malphighian Tubes to be excreted. Because it does not carry oxygen, Grasshopper blood is green.
  • Their body is covered with a hard exoskeleton just like other Insects.

Geographical Range and Habitat

Grasshoppers are found in a variety of Habitats like forests, grasslands, deserts and on mountains.Grasshoppers are not found in the freezing North and South poles.

Behaviour

Grasshoppers are mostly active during the day when it's hot because Grasshoppers and other Insects can’t be very active until their bodies warm up. During the cool morning, they stay still.

They are ferocious feeders and an average Grasshopper can eat 16 time its own weight.

Grasshoppers do not have nests or territories and some Species go on long migrations to find new supplies of food.

Most Species are solitary and only come together to mate, but the Migratory Species sometimes gather in huge groups of millions or even billions of individuals.

A Grasshopper’s Antennae are very sensitive. They help the Grasshopper feel its way around. That’s why Antennae are often called 'Feelers'.

To leap, it pushes off with its long, strong back legs which propel it forward.

Short-Horned Grasshoppers also use their legs to produce various sounds. 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.

Most of Long-Horned Grasshoppers deposit their eggs in the soft tissue of plants or on tree branches. Short-horned Grasshoppers deposit their eggs, in clusters of 15 to 100 or more, underground. They cover the clusters with a fluid that hardens to form a protective cover. The eggs are laid in late summer or fall, and the Nymphs (offspring) emerge in spring.

Some Grasshoppers are adapted to specialized habitats. The South American 'Marellia remipes' spends most of its life on floating vegetation and actively swims and lays eggs on underwater aquatic plants.

Some Grasshoppers spit to protect themselves from their predators or enemies. When a Grasshopper is handled, it spits out a brown liquid. This foul stuff helps keep enemies away. A Grasshopper may also use its strong jaws to bite an enemy.

Diet - Grasshoppers eat plants which includes grasses, leaves and cereal crops.

Predators -  Their predators include birds, beetles, rodents, reptiles, and spiders. Some Flies also eat Grasshopper eggs. The Grasshoppers greatest enemies include various kinds of Flies that lay their eggs in or near Grasshopper eggs. After the Fly eggs hatch, the newborn Flies eat the Grasshopper eggs. Some flies will even lay their eggs on the Grasshoppers body, even while the Grasshopper is flying. The newborn Flies then eat the Grasshopper.

Reproduction

The Adult Grasshoppers gain sexual maturity within 15 days and survive for a span of about 30 days. Grasshopper's Reproductive System consists of the Gonads, the ducts which carry sexual products to the exterior, and accessory glands. In Males, the Testes consist of a number of follicles which hold the spermatocytes as they mature and form packets of elongated spermatozoa. During reproduction, the Male Grasshopper introduces sperm into the ovipositor through its Aedeagus (reproductive organ), and inserts its spermatophore, a package containing the sperm, into the Female's Ovipositor. The sperm enters the eggs through fine canals called Micropyles. The Female then lays the Fertilized Egg Pod, using her Ovipositor and Abdomen to insert the eggs about one to two inches underground, although they can also be laid in plant roots or even manure. The Egg Pod contains several dozens of tightly packed eggs that look like thin rice grains. The eggs stay there through the winter, and hatch when the weather has warmed sufficiently. In temperate zones, many Grasshoppers spend most of their life as eggs through the cooler months (up to 9 months) and the active states (young and adult grasshoppers) live only up to three months. The first Nymph to hatch tunnels up through the ground, and the rest follow. Grasshoppers develop through stages and progressively get larger in body and wing size. This development is referred to as 'Hemimetabolous' or 'Incomplete Metamorphosis' since the young are rather similar in appearance to the adult.

In Folklore and Culture

  • Aesop (620–560 BC), a slave and story-teller who lived in Ancient Greece, told a tale called 'The Ant and the Grasshopper'. In this tale, the Ant worked hard preparing his shelter and stores of food all summer, while the Grasshopper played. When winter came, the Ant was prepared, but the Grasshopper has no shelter or food. He begs to enter the ant's house, but the Ant refuses and the Grasshopper starves.
  • Those who are unable to keep a single subject in focus but keep bringing in inappropriate associations (hopping from one thing to another) are said to have 'a Grasshopper Mind'.
  • In certain countries, Grasshoppers are eaten as a good source of protein. In Mexico  for example, Chapulines are regarded for their high content of protein, minerals and vitamins.
  • In some countries in Africa, Grasshoppers are an important food source, as are other insects, adding proteins and fats to the daily diet, especially in times of food crisis. They are often used in soup.
  • The 1957 film, 'Beginning of the End' features mutated giant Grasshoppers attacking Chicago.
  • In the 1998 movie, 'A Bug's Life', the heroes are the members of an Ant colony, and the lead villain and his henchmen are Grasshoppers.
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