The Orthoptera produce sounds by rubbing their wings or legs. (Usually, male Orthoptera make sounds to attract females during breeding time. Most of the time, females are silent.) The female Orthoptera hatch eggs in the ground and in plants. The Orthoptera are dioecious species (“two houses” in Greek). To produce the eggs, both male and female are needed and they need to breed together. They are hemimetabolous, which means they undergo incomplete metamorphosis (i.e. instead of a pupa stage the young look like small adults). 
The Orthoptera have ears on front legs. Among the grasshoppers, locusts, and crickets, they have small differences. The grasshoppers and locusts have short antennae, but the crickets have long antennae. 
The body of Orthoptera can be divided into three parts: head, thorax, and abdomen. The head contains the face and the antennae. The thorax contains the legs and wings. The abdomen contains with reproductive organs.
The head has large eyes. The large eyes are compound eyes, because lateral ocellus (placed in front of the each compound eye) and median ocellus (another simple eye which placed on the face view) make to forms of the eyes. The antennae are called third eyes. Movable basal segments are called scape, and another movable segment is called pedicel. Rest of the movable antennae is called flagellum, and non movable flagellum is called flagellomere. Lower part of the head has mouth parts. The upper lip is called labrum. Mandibles chew food. Maxillary palpi taste food. Labial palpi are lower lip. The grasshoppers’ cheek is called gena. 
Pronotum is an important area for the thorax to identify the species. Front legs are called prothoracic legs, middle legs are called mesothoracic legs, and jumping legs are called metathoracic legs. Narrow forewings are called tegmina. Leading edge of the forewing is called costal margin and trailing edge of the forewing is called inner margin. The wings and the legs are used to produce the sounds by rubbing those. 
The abdomen is cylindrical shape with tergites (dorsally over lapping plates) and sternites (ventral plates). End of dorsal and ventral valves make an ovipositor which is used to lay the eggs into the ground. It acts as guiding laying the eggs. Male katydids and meadow grasshoppers has projecting cerci. The crickets have long cerci. The ovipositors have three types: cylindrical, projecting, and flattened and sharply upturned. The true crickets have cylindrical ovipositors. The katydids have projecting and flattened and sharply upturned types of the ovipositor. 
Most Orthoptera can produce sounds. They produce sounds to attract mates, to alarm, and to protect their territories from others. (Usually, the male Orthoptera produce the sounds.) By volume and pitch of the sounds, species can be distinguished.
Males rub their wings or legs to produce the sounds. Some of the species grind jaws to produce the sounds. The grasshoppers rub the inside of their jumping legs on edges of their forewings to make the sounds. When they spread their wings, the sounds are amplified.
By sound, smell, touch, and sight, the male Orthoptera attract the females. Each of theses species use different methods to attract the females. The grasshoppers dance by flying. The crickets and the katydids produce two different kinds of sounds. First one is used for long range. When the females come near by the males, the male crickets and katydids produce quieter sounds. Not only the sounds, but also the crickets and katydids use smell to attract the mates. The female giant wetas produce pheromones to attract the males. 
The male Orthoptera insert sperm into female Orthoptera body directly. The sperm packet weights about 60% of the male’s body weight. The female crickets and katydids insert ovipositors into the ground or rotting wood to lay out the eggs. The female grasshoppers use valves on their abdomen instead of the ovipositors to lay out the eggs in the ground or the rotting wood. 
After a few weeks or months, larvae hatch. Some species guard their eggs, but some species do not. Mole crickets lay their eggs in a special chamber and protect the eggs to prevent from spoiling. The larvae look like the adult insects, but they have undeveloped wings and reproductive organs. They do not go through pupa stages, but they develop by molting six to ten times to become the adult insects. 
The Orthoptera insects are easily seen from everywhere. Most of the Orthoptera and the grasshoppers are found in grasslands and forests. Scaley crickets are found on sea shores. Camel crickets are found in caves. Schistocerca gregaria (desert locust) is found from desert. Mole crickets are found in underground. Ant crickets are found from ant’ nests. Turks ground hoppers live only on alpine stream gravel banks. Some species live under the water. Most Orthoptera are herbivorous (eating vegetable), but some of are omnivorous (eating animal and vegetable). Oak bush crickets, green grasshoppers, and mole crickets are carnivores (eating animal). 
The grasshoppers and wasp-mimicking katydid from Central America are active during day, while most of the crickets are active at night. The wasp-mimicking katydid is a harmless insect. Even though it is named wasp, it does not look like a wasp. It lives in sunny places in rain forests. When night comes, wasp-mimicking katydid does not move much or moves slowly. (Because it has orange color body, it might be shown well at night.) 
The Orthoptera like to live themselves. There are exceptions. Sometimes the locusts or grasshoppers unite together as massive swarms. These kinds of swarms are disasters to farmers.
Swarms of locusts
The locusts destroy everything on their way, and they bring lots of damage to crops during harvest time. They appear with thundering sound and cover the sky. When the locusts pass by fields, everything is eaten and nothing is left after the swarm passes by. Small swarms of locusts eat enough food equal to about 2,500 humans. Farmers try to prevent damages by the swarm of the locusts, but wiping out them is not easy work to the farmers. 
One of examples by the swarms of locusts was written in the Bible. Exodus 10:12-15 said, “And the LORD said to Moses, 'Stretch out your hand over Egypt so that locusts will swarm over the land and devour everything growing in the fields, everything left by the hail.' So Moses stretched out his staff over Egypt, and the LORD made an east wind blow across the land all that day and all that night. By morning the wind had brought the locusts; they invaded all Egypt and settled down in every area of the country in great numbers. Never before had there been such a plague of locusts, nor will there ever be again. They covered all the ground until it was black. They devoured all that was left after the hail—everything growing in the fields and the fruit on the trees. Nothing green remained on tree or plant in all the land of Egypt.”
Edible Insect Orthoptera
In this world, about 3,600 species are edible insects and the Orthoptera are one of the examples. The Orthoptera are eaten for food and medical use. (The grasshoppers, locusts, and crickets are the major edible insects from Orthoptera.). The grasshoppers have lots of protein (about 64 percent protein), so they are a very nourishing meal. Caterpillars of many species are rich in potassium, calcium, magnesium, zinc, and iron, as well as B-vitamins. They conserve lots of nutrition that other food sources do not have, so they are good food for old people and growing children. Japanese people eat grasshopper and bee larvae with soy sauce, which is a favorite dish in Japan. 
Cattail Toothpick Grasshopper
Eastern lubber grasshopper
Common Field Grasshopper
Slender gumleaf grasshopper
Northern mole cricket
Fork tailed bush katydid
Robust conehead conehead
Grey bush cricket (Platycleis albopunctata)
- Grasshoppers and Crickets (Orthoptera) The Earth Life
- Anatomy of a Grasshopper North Dakota State University
- Crickets Grasshoppers and Katydids: Orthoptera - Behavior And Reproduction Animal Life Resource
- New locust swarms threaten crop harvests Reuters AlertNet
- Exodus 10:12-15 Biblegateway
- Edible Insects Smithsonian National Zoological Park