Phylogeny

The Orthoptera are divided into two suborders, Caelifera and Ensifera, that have been shown to be monophyletic.^[5][6][7]

Taxonomy

Garden locust (Acanthacris ruficornis), Ghana, family Acrididae

Variegated grasshopper (Zonocerus variegatus), Ghana, family Pyrgomorphidae

Proscopiidae gen. sp. from the Andes of Peru

Taxonomists classify members of the Caelifera and Ensifera into infraorders and superfamilies as follows:^[8][9][10]

• Suborder Caelifera – grasshoppers, pygmy mole crickets and allies
  • Infraorder Acrididea
    • Superfamily Acridoidea – grasshoppers, locusts
    • Superfamily Eumastacoidea – monkey or matchstick grasshoppers and allies
    • Superfamily Locustopsoidea†
    • Superfamily Pneumoroidea – bladder grasshoppers
    • Superfamily Pyrgomorphoidea – gaudy grasshoppers
    • Superfamily Tanaoceroidea – desert long-horned grasshoppers
    • Superfamily Tetrigoidea – ground-hoppers or grouse locusts
    • Superfamily Trigonopterygoidea – leaf grasshoppers
  • Infraorder Tridactylidea
    • Superfamily Dzhajloutshelloidea†
    • Superfamily Regiatoidea†
    • Superfamily Tridactyloidea – pygmy mole crickets and allies
• Suborder Ensifera – crickets
  • Superfamily Grylloidea – crickets, mole crickets
  • Superfamily Hagloidea – grigs and allies
  • Superfamily Phasmomimoidea†
  • Superfamily Rhaphidophoroidea – camel crickets, cave crickets, cave wētā
  • Superfamily Schizodactyloidea – dune crickets
  • Superfamily Stenopelmatoidea – wētā and allies
  • Superfamily Tettigonioidea – katydids / bush crickets
• Incertae sedis
  • Superfamily Elcanoidea† Permian-Paleocene

As pests

Several species of Orthoptera are considered pests of crops and rangelands or seeking warmth in homes by humans. The two groups of Orthoptera that cause the most damage are grasshoppers and locusts. Locust are historically known for wiping out fields of crops in a day. Locust have the ability to eat up to their own body weight in a single day.^[11] Individuals gather in large groups called swarms, these swarms can range up to 80 million individuals that stretch 460 square miles.^[11] Grasshoppers can cause major agricultural damage but not to the documented extent as locust historically have. These insects mainly feed on weeds and grasses, however, during times of drought and high population density they will feed on crops. They are a known pest in soybean fields and will likely feed on these crops once preferred food sources have become scarce.^[12]

As food

Most orthopterans are edible, making up 13% of all insects including some 80 species of grasshoppers being regularly consumed worldwide.^[13] In Madagascar and Oaxaca, grasshoppers and locusts are usually collected early in the morning when it is cooler as the orthopterans are less mobile due to being cold-blooded.^[13] In Thailand, house crickets are commonly reared and eaten; as of 2012, around 20,000 cricket farmers had farms in 53 of their 76 provinces.^[13]

In the second century BCE in Ancient Greece, Diodorus Siculus is known to have called people from Ethiopia Acridophagi, meaning "eaters of locusts."^[13]

In Judaism, the Orthoptera include the only insects considered kosher. The list of dietary laws in the book of Leviticus forbids all flying insects that walk, but makes an exception for certain locusts.^[14] The Torah states the only kosher flying insects with four walking legs have knees that extend above their feet so that they hop.^[15]

As creators of biofuel

With new research showing promise in locating alternative biofuel sources in the gut of insects, grasshoppers are one species of interest. The insect's ability to break down cellulose and lignin without producing greenhouse gases has aroused scientific interest.^[16]