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Silk
Silk is a natural protein fiber, some forms of which can be woven into textiles. The protein fiber of silk is composed mainly of fibroin and is produced by certain insect larvae to form cocoons. The best-known silk is obtained from the cocoons of the larvae of the mulberry silkworm ''Bombyx mori'' reared in captivity (sericulture). The shimmering appearance of silk is due to the triangular prism-like structure of the silk fibre, which allows silk cloth to refract incoming light at different angles, thus producing different colors. Silk is produced by several insects; but, generally, only the silk of moth caterpillars has been used for textile manufacturing. There has been some research into other types of silk, which differ at the molecular level. Silk is mainly produced by the larvae of insects undergoing complete metamorphosis, but some insects, such as webspinners and raspy crickets, produce silk throughout their lives. Silk production also occurs in hymenoptera ( bee ...
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Seal Script
Seal script, also sigillary script () is an ancient style of writing Chinese characters that was common throughout the latter half of the 1st millennium BC. It evolved organically out of the Zhou dynasty bronze script. The Qin variant of seal script eventually became the standard, and was adopted as the formal script for all of China during the Qin dynasty. It was still widely used for decorative engraving and seals (name chops, or signets) in the Han dynasty. The literal translation of the Chinese name for seal script, (), is 'decorative engraving script', a name coined during the Han dynasty, which reflects the then-reduced role of the script for the writing of ceremonial inscriptions. Types The general term seal script can be used to refer to several types of seal script, including the large or great seal script ( ; Japanese ; Korean ; Vietnamese ) and the lesser or small seal script ( ; Japanese ; Korean ; Vietnamese ). Most commonly, without any other clarifying term ...
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Holometabolism
Holometabolism, also called complete metamorphosis, is a form of insect development which includes four life stages: egg, larva, pupa, and imago (or adult). Holometabolism is a synapomorphic trait of all insects in the superorder Endopterygota. Immature stages of holometabolous insects are very different from the mature stage. In some species the holometabolous life cycle prevents larvae from competing with adults because they inhabit different ecological niches. The morphology and behavior of each stage are adapted for different activities. For example, larval traits maximize feeding, growth, and development, while adult traits enable dispersal, mating, and egg laying. Some species of holometabolous insects protect and feed their offspring. Other insect developmental strategies include ametabolism and hemimetabolism. Developmental stages There are four general developmental stages, each with its own morphology and function. Egg The first stage of the insect life cycle is t ...
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Arthropod
Arthropods (, (gen. ποδός)) are invertebrate animals with an exoskeleton, a Segmentation (biology), segmented body, and paired jointed appendages. Arthropods form the phylum Arthropoda. They are distinguished by their jointed limbs and Arthropod cuticle, cuticle made of chitin, often Mineralization (biology), mineralised with calcium carbonate. The arthropod body plan consists of segments, each with a pair of appendages. Arthropods are bilaterally symmetrical and their body possesses an exoskeleton, external skeleton. In order to keep growing, they must go through stages of moulting, a process by which they shed their exoskeleton to reveal a new one. Some species have wings. They are an extremely diverse group, with up to 10 million species. The haemocoel, an arthropod's internal cavity, through which its haemolymph – analogue of blood – circulates, accommodates its interior Organ (anatomy), organs; it has an open circulatory system. Like their exteriors, the internal or ...
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Midge
A midge is any small fly, including species in several families of non-mosquito Nematoceran Diptera. Midges are found (seasonally or otherwise) on practically every land area outside permanently arid deserts and the frigid zones. Some midges, such as many Phlebotominae (sand fly) and Simuliidae (black fly), are vectors of various diseases. Many others play useful roles as prey for insectivores, such as various frogs and swallows. Others are important as detritivores, and form part of various nutrient cycles. The habits of midges vary greatly from species to species, though within any particular family, midges commonly have similar ecological roles. Examples of families that include species of midges include: * Blephariceridae, net-winged midges * Cecidomyiidae, gall midges * Ceratopogonidae, biting midges (also known as no-see-ums or punkies in North Americabr>BugGuide/ref> and sandflies in Australia) * Chaoboridae, phantom midges * Chironomidae, non-biting midges (a ...
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Flea
Flea, the common name for the order Siphonaptera, includes 2,500 species of small flightless insects that live as external parasites of mammals and birds. Fleas live by ingesting the blood of their hosts. Adult fleas grow to about long, are usually brown, and have bodies that are "flattened" sideways or narrow, enabling them to move through their hosts' fur or feathers. They lack wings; their hind legs are extremely well adapted for jumping. Their claws keep them from being dislodged, and their mouthparts are adapted for piercing skin and sucking blood. They can leap 50 times their body length, a feat second only to jumps made by another group of insects, the superfamily of froghoppers. Flea larvae are worm-like, with no limbs; they have chewing mouthparts and feed on organic debris left on their hosts' skin. Genetic evidence indicates that fleas are a specialised lineage of parasitic scorpionflies (Mecoptera) ''sensu lato'', most closely related to the family Nannochor ...
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Lacewing
The insect order Neuroptera, or net-winged insects, includes the lacewings, mantidflies, antlions, and their relatives. The order consists of some 6,000 species. Neuroptera can be grouped together with the Megaloptera and Raphidioptera in the unranked taxon Neuropterida (once known as Planipennia) including: alderflies, fishflies, dobsonflies, and snakeflies. Adult Neuropterans have four membranous wings, all about the same size, with many veins. They have chewing mouthparts, and undergo complete metamorphosis. Neuropterans first appeared during the Permian period, and continued to diversify through the Mesozoic era. During this time, several unusually large forms evolved, especially in the extinct family Kalligrammatidae, often called "the butterflies of the Jurassic" for their large, patterned wings. Anatomy and biology Neuropterans are soft-bodied insects with relatively few specialized features. They have large lateral compound eyes, and may or may not also have o ...
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Beetle
Beetles are insects that form the order Coleoptera (), in the superorder Endopterygota. Their front pair of wings are hardened into wing-cases, elytra, distinguishing them from most other insects. The Coleoptera, with about 400,000 described species, is the largest of all orders, constituting almost 40% of described insects and 25% of all known animal life-forms; new species are discovered frequently, with estimates suggesting that there are between 0.9 and 2.1 million total species. Found in almost every habitat except the sea and the polar regions, they interact with their ecosystems in several ways: beetles often feed on plants and fungi, break down animal and plant debris, and eat other invertebrates. Some species are serious agricultural pests, such as the Colorado potato beetle, while others such as Coccinellidae (ladybirds or ladybugs) eat aphids, scale insects, thrips, and other plant-sucking insects that damage crops. Beetles typically have a particularly hard e ...
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Leafhopper
A leafhopper is the common name for any species from the family Cicadellidae. These minute insects, colloquially known as hoppers, are plant feeders that suck plant sap from grass, shrubs, or trees. Their hind legs are modified for jumping, and are covered with hairs that facilitate the spreading of a secretion over their bodies that acts as a water repellent and carrier of pheromones. They undergo a partial metamorphosis, and have various host associations, varying from very generalized to very specific. Some species have a cosmopolitan distribution, or occur throughout the temperate and tropical regions. Some are pests or vectors of plant viruses and phytoplasmas. The family is distributed all over the world, and constitutes the second-largest hemipteran family, with at least 20,000 described species. They belong to a lineage traditionally treated as infraorder Cicadomorpha in the suborder Auchenorrhyncha, but as the latter taxon is probably not monophyletic, many modern au ...
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Thrips
Thrips ( order Thysanoptera) are minute (mostly long or less), slender insects with fringed wings and unique asymmetrical mouthparts. Different thrips species feed mostly on plants by puncturing and sucking up the contents, although a few are predators. Entomologists have described approximately 6,000 species. They fly only weakly and their feathery wings are unsuitable for conventional flight; instead, thrips exploit an unusual mechanism, clap and fling, to create lift using an unsteady circulation pattern with transient vortices near the wings. Many thrips species are pests of commercially important crops. A few species serve as vectors for over 20 viruses that cause plant disease, especially the Tospoviruses. Some species of thrips are beneficial as pollinators or as predators of other insects or mites. In the right conditions, such as in greenhouses, many species can exponentially increase in population size and form large swarms because of a lack of natural predators ...
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Mayfly
Mayflies (also known as shadflies or fishflies in Canada and the upper Midwestern United States, as Canadian soldiers in the American Great Lakes region, and as up-winged flies in the United Kingdom) are aquatic insects belonging to the order Ephemeroptera. This order is part of an ancient group of insects termed the Palaeoptera, which also contains dragonflies and damselflies. Over 3,000 species of mayfly are known worldwide, grouped into over 400 genera in 42 families. Mayflies have ancestral traits that were probably present in the first flying insects, such as long tails and wings that do not fold flat over the abdomen. Their immature stages are aquatic fresh water forms (called "naiads" or "nymphs"), whose presence indicates a clean, unpolluted and highly oxygenated aquatic environment. They are unique among insect orders in having a fully winged terrestrial preadult stage, the subimago, which moults into a sexually mature adult, the imago. Mayflies "hatch" (emerge ...
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Silverfish
The silverfish (''Lepisma saccharinum'') is a species of small, primitive, wingless insect in the order Zygentoma (formerly Thysanura). Its common name derives from the insect's silvery light grey colour, combined with the fish-like appearance of its movements. The scientific name (''L. saccharinum'') indicates that the silverfish's diet consists of carbohydrates such as sugar or starches. While the common name ''silverfish'' is used throughout the global literature to refer to various species of Zygentoma, the Entomological Society of America restricts use of the term solely for ''Lepisma saccharinum''. Description The silverfish is a nocturnal insect typically long. Its abdomen tapers at the end, giving it a fish-like appearance. The newly hatched are whitish, but develop a greyish hue and metallic shine as they get older. It has two long cerci and one terminal filament at the tip of the abdomen between the cerci. It also has two small compound eyes, although other mem ...
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Wasp
A wasp is any insect of the narrow-waisted suborder Apocrita of the order Hymenoptera which is neither a bee nor an ant; this excludes the broad-waisted sawflies (Symphyta), which look somewhat like wasps, but are in a separate suborder. The wasps do not constitute a clade, a complete natural group with a single ancestor, as bees and ants are deeply nested within the wasps, having evolved from wasp ancestors. Wasps that are members of the clade Aculeata can Stinger, sting their prey. The most commonly known wasps, such as yellowjackets and hornets, are in the family Vespidae and are Eusociality, eusocial, living together in a nest with an egg-laying queen and non-reproducing workers. Eusociality is favoured by the unusual haplodiploid system of sex-determination system, sex determination in Hymenoptera, as it makes sisters exceptionally closely related to each other. However, the majority of wasp species are solitary, with each adult female living and breeding independently ...
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