Misplaced Pages

#669330

124-424: The pupae of different groups of insects have different names such as chrysalis for the pupae of butterflies and tumbler for those of the mosquito family. Pupae may further be enclosed in other structures such as cocoons , nests , or shells . The pupal stage follows the larval stage, or in some cases a prepupal stage, and precedes adulthood ( imago ) in insects with complete metamorphosis. The pupa

248-401: A bave . Bave diameters for tussah silk can reach 65 μm. See cited reference for cross-sectional SEM photographs. Silk has a smooth, soft texture that is not slippery, unlike many synthetic fibers . Silk is one of the strongest natural fibers, but it loses up to 20% of its strength when wet. It has a good moisture regain of 11%. Its elasticity is moderate to poor: if elongated even

372-637: A diapause (resting) stage, and the hatching may take place only in spring. Some temperate region butterflies, such as the Camberwell beauty , lay their eggs in the spring and have them hatch in the summer. Butterfly larvae, or caterpillars, consume plant leaves and spend practically all of their time searching for and eating food. Although most caterpillars are herbivorous, a few species are predators : Spalgis epius eats scale insects , while lycaenids such as Liphyra brassolis are myrmecophilous , eating ant larvae. Some larvae, especially those of

496-493: A butterfly cannot fly until the wings are unfolded. A newly emerged butterfly needs to spend some time inflating its wings with hemolymph and letting them dry, during which time it is extremely vulnerable to predators. The colourful patterns on many butterfly wings tell potential predators that they are toxic. Hence, the genetic basis of wing pattern formation can illuminate both the evolution of butterflies as well as their developmental biology . The colour of butterfly wings

620-570: A butterfly through metamorphosis has held great appeal to mankind. To transform from the miniature wings visible on the outside of the pupa into large structures usable for flight, the pupal wings undergo rapid mitosis and absorb a great deal of nutrients. If one wing is surgically removed early on, the other three will grow to a larger size. In the pupa, the wing forms a structure that becomes compressed from top to bottom and pleated from proximal to distal ends as it grows, so that it can rapidly be unfolded to its full adult size. Several boundaries seen in

744-417: A common family. In some species, such as the great spangled fritillary , the eggs are deposited close to but not on the food plant. This most likely happens when the egg overwinters before hatching and where the host plant loses its leaves in winter, as do violets in this example. The egg stage lasts a few weeks in most butterflies, but eggs laid close to winter, especially in temperate regions, go through

868-576: A few butterflies (e.g., harvesters ) eat harmful insects, and a few are predators of ants , while others live as mutualists in association with ants. Culturally, butterflies are a popular motif in the visual and literary arts. The Smithsonian Institution says "butterflies are certainly one of the most appealing creatures in nature". The Oxford English Dictionary derives the word straightforwardly from Old English butorflēoge , butter-fly; similar names in Old Dutch and Old High German show that

992-444: A few species. Some butterflies have organs of hearing and some species make stridulatory and clicking sounds. Many species of butterfly maintain territories and actively chase other species or individuals that may stray into them. Some species will bask or perch on chosen perches. The flight styles of butterflies are often characteristic and some species have courtship flight displays. Butterflies can only fly when their temperature

1116-606: A hard-ridged outer layer of shell, called the chorion . This is lined with a thin coating of wax which prevents the egg from drying out before the larva has had time to fully develop. Each egg contains a number of tiny funnel-shaped openings at one end, called micropyles ; the purpose of these holes is to allow sperm to enter and fertilize the egg. Butterfly eggs vary greatly in size and shape between species, but are usually upright and finely sculptured. Some species lay eggs singly, others in batches. Many females produce between one hundred and two hundred eggs. Butterfly eggs are fixed to

1240-424: A large satin waistcoat with flaps, were got up, of which the silk was perfect, but the lining entirely gone ... from the thread giving way ... No articles of dress of woollen cloth have yet been found.' Silk is a poor conductor of electricity and thus susceptible to static cling . Silk has a high emissivity for infrared light, making it feel cool to the touch. Unwashed silk chiffon may shrink up to 8% due to

1364-508: A leaf before eggs are laid on it. Many butterflies use chemical signals, pheromones ; some have specialized scent scales ( androconia ) or other structures ( coremata or "hair pencils" in the Danaidae). Vision is well developed in butterflies and most species are sensitive to the ultraviolet spectrum. Many species show sexual dimorphism in the patterns of UV reflective patches. Colour vision may be widespread but has been demonstrated in only

SECTION 10

#1732772362670

1488-416: A leaf with a special glue which hardens rapidly. As it hardens it contracts, deforming the shape of the egg. This glue is easily seen surrounding the base of every egg forming a meniscus. The nature of the glue has been little researched but in the case of Pieris brassicae , it begins as a pale yellow granular secretion containing acidophilic proteins. This is viscous and darkens when exposed to air, becoming

1612-738: A long history of a formative textile industry in ancient China, this find of silk textiles employing "complicated techniques" of weaving and dyeing provides direct evidence for silks dating before the Mawangdui -discovery and other silks dating to the Han dynasty (202 BC – 220 AD). Silk is described in a chapter of the Fan Shengzhi shu from the Western Han (202 BC – 9 AD). There is a surviving calendar for silk production in an Eastern Han (25–220 AD) document. The two other known works on silk from

1736-547: A longer lifespan of several months as adults. The thorax of the butterfly is devoted to locomotion. Each of the three thoracic segments has two legs (among nymphalids , the first pair is reduced and the insects walk on four legs). The second and third segments of the thorax bear the wings. The leading edges of the forewings have thick veins to strengthen them, and the hindwings are smaller and more rounded and have fewer stiffening veins. The forewings and hindwings are not hooked together ( as they are in moths ) but are coordinated by

1860-452: A necessity for their successful establishment. Many butterflies, such as the painted lady , monarch, and several danaine migrate for long distances. These migrations take place over a number of generations and no single individual completes the whole trip. The eastern North American population of monarchs can travel thousands of miles south-west to overwintering sites in Mexico . There is

1984-440: A number of small firms and cooperatives emerged. Among the most prominent of these was the cooperative utopian Northampton Association for Education and Industry, of which Sojourner Truth was a member. Following the destructive Mill River Flood of 1874 , one manufacturer, William Skinner , relocated his mill from Williamsburg to the then-new city of Holyoke . Over the next 50 years he and his sons would maintain relations between

2108-515: A one-way passage out; such features facilitate the escape of the adult insect after it emerges from the pupal skin. Some pupae remain inside the exoskeleton of the final larval instar and this last larval "shell" is called a puparium (plural, puparia). Flies of the group Muscomorpha have puparia, as do members of the order Strepsiptera , and the Hemipteran family Aleyrodidae . Butterflies Butterflies are winged insects from

2232-459: A protective covering for the pupa. Cocoons may be tough or soft, opaque or translucent, solid or meshlike, of various colors, or composed of multiple layers, depending on the type of insect larva producing it. Many moth caterpillars shed the larval hairs ( setae ) and incorporate them into the cocoon; if these are urticating hairs then the cocoon is also irritating to the touch. Some larvae attach small twigs, fecal pellets or pieces of vegetation to

2356-658: A reverse migration in the spring. It has recently been shown that the British painted lady undertakes a 9,000-mile round trip in a series of steps by up to six successive generations, from tropical Africa to the Arctic Circle — almost double the length of the famous migrations undertaken by monarch. Spectacular large-scale migrations associated with the monsoon are seen in peninsular India. Migrations have been studied in more recent times using wing tags and also using stable hydrogen isotopes . Butterflies navigate using

2480-412: A segmented palp. Adjoining these is the labium-hypopharynx which houses a tubular spinneret which is able to extrude silk. Caterpillars such as those in the genus Calpodes (family Hesperiidae) have a specialized tracheal system on the 8th segment that function as a primitive lung. Butterfly caterpillars have three pairs of true legs on the thoracic segments and up to six pairs of prolegs arising from

2604-435: A silken girdle may be spun to keep the pupa in a head-up position. Most of the tissues and cells of the larva are broken down inside the pupa, as the constituent material is rebuilt into the imago. The structure of the transforming insect is visible from the exterior, with the wings folded flat on the ventral surface and the two halves of the proboscis, with the antennae and the legs between them. The pupal transformation into

SECTION 20

#1732772362670

2728-417: A small amount, it remains stretched. It can be weakened if exposed to too much sunlight. It may also be attacked by insects, especially if left dirty. One example of the durable nature of silk over other fabrics is demonstrated by the recovery in 1840 of silk garments from a wreck of 1782 : 'The most durable article found has been silk; for besides pieces of cloaks and lace, a pair of black satin breeches, and

2852-421: A surface by a Velcro -like arrangement of a silken pad spun by the caterpillar , usually cemented to the underside of a perch, and the cremastral hook or hooks protruding from the rear of the chrysalis or cremaster at the tip of the pupal abdomen by which the caterpillar fixes itself to the pad of silk. ( Gr. kremastos 'suspended') Like other types of pupae, the chrysalis stage in most butterflies

2976-410: A time-compensated sun compass. They can see polarized light and therefore orient even in cloudy conditions. The polarized light near the ultraviolet spectrum appears to be particularly important. Many migratory butterflies live in semi-arid areas where breeding seasons are short. The life histories of their host plants also influence butterfly behaviour. Butterflies in their adult stage can live from

3100-541: A total of about 20,000 species. Traditionally, butterflies have been divided into the superfamilies Papilionoidea and the moth-like Hedyloidea . Recent work has discovered that Hedylidae, the only family within Hedyloidea, is nested within the Papilionoidea, meaning that Papilionoidea would be synonymous with Rhopalocera. The relationships between the rest of the 6 families are extremely well resolved, which

3224-470: A trend towards multivoltinism . Courtship is often aerial and often involves pheromones . Butterflies then land on the ground or on a perch to mate. Copulation takes place tail-to-tail and may last from minutes to hours. Simple photoreceptor cells located at the genitals are important for this and other adult behaviours. The male passes a spermatophore to the female; to reduce sperm competition, he may cover her with his scent, or in some species such as

3348-486: A tubular proboscis which is curled up at rest and expanded when needed to feed. The first and second maxillae bear palps which function as sensory organs. Some species have a reduced proboscis or maxillary palps and do not feed as adults. Many Heliconius butterflies also use their proboscis to feed on pollen; in these species only 20% of the amino acids used in reproduction come from larval feeding, which allow them to develop more quickly as caterpillars, and gives them

3472-437: A water-insoluble, rubbery material which soon sets solid. Butterflies in the genus Agathymus do not fix their eggs to a leaf; instead, the newly laid eggs fall to the base of the plant. Eggs are almost invariably laid on plants. Each species of butterfly has its own host plant range and while some species of butterfly are restricted to just one species of plant, others use a range of plant species, often including members of

3596-422: A week to nearly a year depending on the species. Many species have long larval life stages while others can remain dormant in their pupal or egg stages and thereby survive winters. The Melissa Arctic ( Oeneis melissa ) overwinters twice as a caterpillar. Butterflies may have one or more broods per year. The number of generations per year varies from temperate to tropical regions with tropical regions showing

3720-416: A white-colored silk thread with no mineral on the surface. The pupae are killed by either dipping them in boiling water before the adult moths emerge or by piercing them with a needle. These factors all contribute to the ability of the whole cocoon to be unravelled as one continuous thread, permitting a much stronger cloth to be woven from the silk. Wild silks also tend to be more difficult to dye than silk from

3844-493: Is a non-feeding, usually sessile stage, or highly active as in mosquitoes. It is during the pupal stage that the adult structures of the insect are formed while the larval structures are broken down. The adult structures grow from imaginal discs . The pupal stage may last weeks, months, or even years, depending on temperature and the species of insect. For example, the pupal stage lasts eight to fifteen days in monarch butterflies . The pupa may enter dormancy or diapause until

Pupa - Misplaced Pages Continue

3968-450: Is above 27 °C (81 °F); when it is cool, they can position themselves to expose the underside of the wings to the sunlight to heat themselves up. If their body temperature reaches 40 °C (104 °F), they can orientate themselves with the folded wings edgewise to the sun. Basking is an activity which is more common in the cooler hours of the morning. Some species have evolved dark wingbases to help in gathering more heat and this

4092-509: Is composed mostly of beta-sheets , due to a 59-mer amino acid repeat sequence with some variations. The flat surfaces of the fibrils reflect light at many angles, giving silk a natural sheen. The cross-section from other silkworms can vary in shape and diameter: crescent-like for Anaphe and elongated wedge for tussah . Silkworm fibers are naturally extruded from two silkworm glands as a pair of primary filaments (brin), which are stuck together, with sericin proteins that act like glue , to form

4216-547: Is concentrated in the Coimbatore , Erode , Bhagalpuri , Tiruppur , Salem , and Dharmapuri districts. Hyderabad , Andhra Pradesh , and Gobichettipalayam , Tamil Nadu , were the first locations to have automated silk reeling units in India. In the northeastern state of Assam , three different types of indigenous variety of silk are produced, collectively called Assam silk : Muga silk , Eri silk and Pat silk . Muga,

4340-413: Is contained in a protective silk case called a cocoon . The pupa of some species such as the hornet moth develops sharp ridges around the outside called adminicula that allow the pupa to move from its place of concealment inside a tree trunk when it is time for the adult to emerge. Pupa, chrysalis, and cocoon are frequently confused, but are quite distinct from each other. The pupa is the stage between

4464-458: Is derived from tiny structures called scales, each of which have their own pigments . In Heliconius butterflies, there are three types of scales: yellow/white, black, and red/orange/brown scales. Some mechanism of wing pattern formation are now being solved using genetic techniques. For instance, a gene called cortex determines the colour of scales: deleting cortex turned black and red scales yellow. Mutations, e.g. transposon insertions of

4588-403: Is especially evident in alpine forms. As in many other insects, the lift generated by butterflies is more than can be accounted for by steady-state, non-transitory aerodynamics . Studies using Vanessa atalanta in a wind tunnel show that they use a wide variety of aerodynamic mechanisms to generate force. These include wake capture , vortices at the wing edge, rotational mechanisms and

4712-410: Is extruded and inserted into the female's vagina. A spermatophore is deposited in the female, following which the sperm make their way to a seminal receptacle where they are stored for later use. In both sexes, the genitalia are adorned with various spines, teeth, scales and bristles, which act to prevent the butterfly from mating with an insect of another species. After it emerges from its pupal stage,

4836-509: Is forbidden. Modern attire has raised a number of issues, including, for instance, the permissibility of wearing silk neckties , which are masculine articles of clothing. In the Odyssey , 19.233, when Odysseus, while pretending to be someone else, is questioned by Penelope about her husband's clothing, he says that he wore a shirt "gleaming like the skin of a dried onion" (varies with translations, literal translation here) which could refer to

4960-451: Is good, especially in some species in the blue/violet range. The antennae are composed of many segments and have clubbed tips (unlike moths that have tapering or feathery antennae). The sensory receptors are concentrated in the tips and can detect odours. Taste receptors are located on the palps and on the feet. The mouthparts are adapted to sucking and the mandibles are usually reduced in size or absent. The first maxillae are elongated into

5084-581: Is native to the Americas, but in the nineteenth century or before, spread across the world, and is now found in Australia, New Zealand, other parts of Oceania, and the Iberian Peninsula . It is not clear how it dispersed; adults may have been blown by the wind or larvae or pupae may have been accidentally transported by humans, but the presence of suitable host plants in their new environment was

Pupa - Misplaced Pages Continue

5208-584: Is now part of Malaysia , a second generation of silkworm was being imported as early as 1764 for the country's silk textile industry, especially songket . However, since the 1980s, Malaysia is no longer engaged in sericulture but does plant mulberry trees. In Vietnamese legend, silk appeared in the first millennium AD and is still being woven today. The process of silk production is known as sericulture . The entire production process of silk can be divided into several steps which are typically handled by different entities. Extracting raw silk starts by cultivating

5332-531: 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

5456-402: Is often called metamorphosis , metamorphosis is really the whole series of changes that an insect undergoes from egg to adult. When emerging, the butterfly uses a liquid, sometimes called cocoonase , which softens the shell of the chrysalis. Additionally, it uses two sharp claws located on the thick joints at the base of the forewings to help make its way out. Having emerged from the chrysalis,

5580-402: Is one in which there is little movement. However, some butterfly pupae are capable of moving the abdominal segments to produce sounds or to scare away potential predators . Within the chrysalis, growth and differentiation occur. The adult butterfly emerges (ecloses) from this and expands its wings by pumping haemolymph into the wing veins. Although this sudden and rapid change from pupa to imago

5704-531: Is potentially large when compared with other natural fibers. A life-cycle assessment of Indian silk production shows that the production process has a large carbon and water footprint, mainly due to the fact that it is an animal-derived fiber and more inputs such as fertilizer and water are needed per unit of fiber produced. Silk fibers from the Bombyx mori silkworm have a triangular cross section with rounded corners, 5–10  μm wide. The fibroin-heavy chain

5828-465: Is restricted to the males, and studies have suggested that the nutrients collected may be provided as a nuptial gift , along with the spermatophore, during mating. In hilltopping , males of some species seek hilltops and ridge tops, which they patrol in search for females. Since it usually occurs in species with low population density, it is assumed these landscape points are used as meeting places to find mates. Butterflies use their antennae to sense

5952-415: Is soaked in extremely cold water and bleached before dyeing to remove the natural yellow coloring of Thai silk yarn. To do this, skeins of silk thread are immersed in large tubs of hydrogen peroxide . Once washed and dried, the silk is woven on a traditional hand-operated loom. The Rajshahi Division of northern Bangladesh is the hub of the country's silk industry. There are three types of silk produced in

6076-698: Is summarized in the below cladogram. Papilionidae [REDACTED] Hedylidae [REDACTED] Hesperiidae [REDACTED] Pieridae [REDACTED] Nymphalidae [REDACTED] Lycaenidae [REDACTED] Riodinidae [REDACTED] Butterfly adults are characterized by their four scale-covered wings, which give the Lepidoptera their name ( Ancient Greek λεπίς lepís, scale + πτερόν pterón, wing). These scales give butterfly wings their colour: they are pigmented with melanins that give them blacks and browns, as well as uric acid derivatives and flavones that give them yellows, but many of

6200-405: Is taken up by the gut, but there may also be large silk glands, and special glands which secrete distasteful or toxic substances. The developing wings are present in later stage instars and the gonads start development in the egg stage. When the larva is fully grown, hormones such as prothoracicotropic hormone (PTTH) are produced. At this point the larva stops feeding, and begins "wandering" in

6324-407: Is the capability of making sounds or vibrations to scare potential predators. A few species use chemical defenses including toxic secretions. The pupae of social hymenopterans are protected by adult members of the hive. Based on the presence or absence of articulated mandibles that are employed in emerging from a cocoon or pupal case, the pupae can be classified in to two types: Based on whether

SECTION 50

#1732772362670

6448-594: Is the presence of the silk protein fibroin in soil samples from two tombs at the neolithic site Jiahu in Henan , which date back about 8,500 years. The earliest surviving example of silk fabric dates from about 3630 BC, and was used as the wrapping for the body of a child at a Yangshao culture site in Qingtaicun near Xingyang , Henan. Legend gives credit for developing silk to a Chinese empress, Leizu (Hsi-Ling-Shih, Lei-Tzu). Silks were originally reserved for

6572-479: Is the second largest producer of silk in the world after China. About 97% of the raw mulberry silk comes from six Indian states, namely, Andhra Pradesh , Karnataka , Jammu and Kashmir , Tamil Nadu , Bihar , and West Bengal . North Bangalore, the upcoming site of a $ 20 million "Silk City" Ramanagara and Mysore , contribute to a majority of silk production in Karnataka. In Tamil Nadu , mulberry cultivation

6696-461: The Cretaceous . Butterflies have a four-stage life cycle , and like other holometabolous insects they undergo complete metamorphosis . Winged adults lay eggs on the food plant on which their larvae , known as caterpillars , will feed. The caterpillars grow, sometimes very rapidly, and when fully developed, pupate in a chrysalis . When metamorphosis is complete, the pupal skin splits,

6820-634: The Great Palace complex in Constantinople, and the cloth produced was used in imperial robes or in diplomacy, as gifts to foreign dignitaries. The remainder was sold at very high prices. Italy was the most important producer of silk during the Medieval age. The first center to introduce silk production to Italy was the city of Catanzaro during the 11th century in the region of Calabria . The silk of Catanzaro supplied almost all of Europe and

6944-479: The Lycaenidae , form mutual associations with ants. They communicate with the ants using vibrations that are transmitted through the substrate as well as using chemical signals. The ants provide some degree of protection to these larvae and they in turn gather honeydew secretions . Large blue ( Phengaris arion ) caterpillars trick Myrmica ants into taking them back to the ant colony where they feed on

7068-730: The Torah , a scarlet cloth item called in Hebrew "sheni tola'at" שני תולעת – literally "crimson of the worm" – is described as being used in purification ceremonies, such as those following a leprosy outbreak (Leviticus 14), alongside cedar wood and hyssop ( za'atar ). Eminent scholar and leading medieval translator of Jewish sources and books of the Bible into Arabic , Rabbi Saadia Gaon , translates this phrase explicitly as "crimson silk" – חריר קרמז حرير قرمز. In Islamic teachings, Muslim men are forbidden to wear silk. Many religious jurists believe

7192-474: The Weis-Fogh ' clap-and-fling ' mechanism. Butterflies are able to change from one mode to another rapidly. Butterflies are threatened in their early stages by parasitoids and in all stages by predators, diseases and environmental factors. Braconid and other parasitic wasps lay their eggs in lepidopteran eggs or larvae and the wasps' parasitoid larvae devour their hosts, usually pupating inside or outside

7316-521: The Yayoi period . The silk industry was dominant from the 1930s to 1950s, but is less common now. Silk from East Asia had declined in importance after silkworms were smuggled from China to the Byzantine Empire. However, in 1845, an epidemic of flacherie among European silkworms devastated the silk industry there. This led to a demand for silk from China and Japan , where as late as

7440-455: The ZW sex-determination system where females are the heterogametic sex (ZW) and males homogametic (ZZ). Butterflies are distributed worldwide except Antarctica, totalling some 18,500 species. Of these, 775 are Nearctic ; 7,700 Neotropical ; 1,575 Palearctic ; 3,650 Afrotropical ; and 4,800 are distributed across the combined Oriental and Australian / Oceania regions. The monarch butterfly

7564-540: The lepidopteran suborder Rhopalocera , characterized by large, often brightly coloured wings that often fold together when at rest, and a conspicuous, fluttering flight. The group comprises the superfamilies Hedyloidea (moth-butterflies in the Americas) and Papilionoidea (all others). The oldest butterfly fossils have been dated to the Paleocene , about 56 million years ago, though molecular likely originated in

SECTION 60

#1732772362670

7688-402: The monarch and the painted lady , migrate over long distances. Many butterflies are attacked by parasites or parasitoids , including wasps , protozoans , flies , and other invertebrates, or are preyed upon by other organisms. Some species are pests because in their larval stages they can damage domestic crops or trees; other species are agents of pollination of some plants. Larvae of

7812-600: The non-coding DNA around the cortex gene can turn a black-winged butterfly into a butterfly with a yellow wing band. When the butterfly Bicyclus anynana is subjected to repeated inbreeding in the laboratory, there is a dramatic decrease in egg hatching. This severe inbreeding depression is considered to be likely due to a relatively high mutation rate to recessive alleles with substantial damaging effects and infrequent episodes of inbreeding in nature that might otherwise purge such mutations. Although B. anynana experiences inbreeding depression when forcibly inbred in

7936-476: The 12th century. Other Italian cities involved in silk production were Genoa , Venice , and Florence . The Piedmont area of Northern Italy became a major silk producing area when water-powered silk throwing machines were developed. The Silk Exchange in Valencia from the 15th century—where previously in 1348 also perxal ( percale ) was traded as some kind of silk—illustrates the power and wealth of one of

8060-595: The 17th century. James I attempted to establish silk production in England, purchasing and planting 100,000 mulberry trees, some on land adjacent to Hampton Court Palace , but they were of a species unsuited to the silk worms, and the attempt failed. In 1732 John Guardivaglio set up a silk throwing enterprise at Logwood mill in Stockport ; in 1744, Burton Mill was erected in Macclesfield ; and in 1753 Old Mill

8184-646: The American silk industry and its counterparts in Japan, and expanded their business to the point that by 1911, the Skinner Mill complex contained the largest silk mill under one roof in the world, and the brand Skinner Fabrics had become the largest manufacturer of silk satins internationally. Other efforts later in the 19th century would also bring the new silk industry to Paterson, New Jersey , with several firms hiring European-born textile workers and granting it

8308-497: The Ancient Greek term χρυσός ( chrysós ) for gold. When the caterpillar is fully grown, it makes a button of silk which it uses to fasten its body to a leaf or a twig. Then the caterpillar's skin comes off for the final time. Under this old skin is a hard skin called a chrysalis. Because chrysalises are often showy and are formed in the open, they are the most familiar examples of pupae. Most chrysalides are attached to

8432-540: The Apollos ( Parnassius ) plugs her genital opening to prevent her from mating again. The vast majority of butterflies have a four-stage life cycle: egg , larva (caterpillar), pupa (chrysalis) and imago (adult). In the genera Colias , Erebia , Euchloe , and Parnassius , a small number of species are known that reproduce semi-parthenogenetically ; when the female dies, a partially developed larva emerges from her abdomen. Butterfly eggs are protected by

8556-591: The Chinese monopoly . Nonetheless, sericulture reached Korea with technological aid from China around 200 BC, the ancient Kingdom of Khotan by AD 50, and India by AD 140. In the ancient era, silk from China was the most lucrative and sought-after luxury item traded across the Eurasian continent, and many civilizations, such as the ancient Persians, benefited economically from trade. Archaeological evidence indicates that sericulture has been practiced since

8680-567: The Chinese word "sī" and other Asian sources—compare Mandarin sī "silk", Manchurian sirghe , Mongolian sirkek . The production of silk originated in China in the Neolithic period, although it would eventually reach other places of the world ( Yangshao culture, 4th millennium BC). Silk production remained confined to China until the Silk Road opened at some point during

8804-649: The Han period are lost. The first evidence of the long distance silk trade is the finding of silk in the hair of an Egyptian mummy of the 21st dynasty, c.1070 BC. The silk trade reached as far as the Indian subcontinent , the Middle East , Europe , and North Africa . This trade was so extensive that the major set of trade routes between Europe and Asia came to be known as the Silk Road . The emperors of China strove to keep knowledge of sericulture secret to maintain

8928-634: The Japanese silk industry and its position as the lead silk exporter of the world. Today, China exports the largest volume of raw silk in the world. Silk has a long history in India. It is known as Resham in eastern and north India, and Pattu in southern parts of India . Recent archaeological discoveries in Harappa and Chanhu-daro suggest that sericulture , employing wild silk threads from native silkworm species, existed in South Asia during

9052-530: The Middle East by Peter Gaddum . Wild silk taken from the nests of native caterpillars was used by the Aztecs to make containers and as paper. Silkworms were introduced to Oaxaca from Spain in the 1530s and the region profited from silk production until the early 17th century, when the king of Spain banned export to protect Spain's silk industry. Silk production for local consumption has continued until

9176-430: The abdomen, generally with short prolegs on segments 3–6 and 10; the three pairs of true legs on the thorax have five segments each. Many are well camouflaged; others are aposematic with bright colours and bristly projections containing toxic chemicals obtained from their food plants. The pupa or chrysalis, unlike that of moths, is not wrapped in a cocoon. Many butterflies are sexually dimorphic . Most butterflies have

9300-405: The abdominal segments. These prolegs have rings of tiny hooks called crochets that are engaged hydrostatically and help the caterpillar grip the substrate. The epidermis bears tufts of setae , the position and number of which help in identifying the species. There is also decoration in the form of hairs, wart-like protuberances, horn-like protuberances and spines. Internally, most of the body cavity

9424-502: The adult colour pattern are marked by changes in the expression of particular transcription factors in the early pupa. The reproductive stage of the insect is the winged adult or imago . The surface of both butterflies and moths is covered by scales, each of which is an outgrowth from a single epidermal cell. The head is small and dominated by the two large compound eyes . These are capable of distinguishing flower shapes or motion but cannot view distant objects clearly. Colour perception

9548-433: The adult insect climbs out, expands its wings to dry, and flies off. Some butterflies, especially in the tropics, have several generations in a year, while others have a single generation, and a few in cold locations may take several years to pass through their entire life cycle. Butterflies are often polymorphic , and many species make use of camouflage , mimicry , and aposematism to evade their predators. Some, like

9672-467: The air for wind and scents. The antennae come in various shapes and colours; the hesperiids have a pointed angle or hook to the antennae, while most other families show knobbed antennae. The antennae are richly covered with sensory organs known as sensillae . A butterfly's sense of taste is coordinated by chemoreceptors on the tarsi , or feet, which work only on contact, and are used to determine whether an egg-laying insect's offspring will be able to feed on

9796-434: The ant eggs and larvae in a parasitic relationship. Caterpillars mature through a series of developmental stages known as instars . Near the end of each stage, the larva undergoes a process called apolysis , mediated by the release of a series of neurohormones . During this phase, the cuticle , a tough outer layer made of a mixture of chitin and specialized proteins , is released from the softer epidermis beneath, and

9920-412: The appropriate season to emerge as an adult insect. In temperate climates pupae usually stay dormant during winter, while in the tropics pupae usually do so during the dry season . Insects emerge (eclose) from pupae by splitting the pupal case. Most butterflies emerge in the morning. In mosquitoes, the emergence is in the evening or night. In fleas, the process is triggered by vibrations that indicate

10044-658: The blues, greens, reds and iridescent colours are created by structural coloration produced by the micro-structures of the scales and hairs. As in all insects, the body is divided into three sections: the head, thorax , and abdomen . The thorax is composed of three segments, each with a pair of legs. In most families of butterfly the antennae are clubbed, unlike those of moths which may be threadlike or feathery. The long proboscis can be coiled when not in use for sipping nectar from flowers. Nearly all butterflies are diurnal , have relatively bright colours, and hold their wings vertically above their bodies when at rest, unlike

10168-405: The butterfly will usually sit on the empty shell in order to expand and harden its wings. However, if the chrysalis was near the ground (such as if it fell off from its silk pad), the butterfly would find another vertical surface to rest upon and harden its wings (such as a wall or fence). Moth pupae are usually dark in color and either formed in underground cells, loose in the soil, or their pupa

10292-486: The cultivated silkworm. A technique known as demineralizing allows the mineral layer around the cocoon of wild silk moths to be removed, leaving only variability in color as a barrier to creating a commercial silk industry based on wild silks in the parts of the world where wild silk moths thrive, such as in Africa and South America. Silk use in fabric was first developed in ancient China. The earliest evidence for silk

10416-441: The desiccated husk. Most wasps are very specific about their host species and some have been used as biological controls of pest butterflies like the large white butterfly . When the small cabbage white was accidentally introduced to New Zealand, it had no natural enemies. In order to control it, some pupae that had been parasitised by a chalcid wasp were imported, and natural control was thus regained. Some flies lay their eggs on

10540-511: The domesticated varieties in colour and texture and are therefore less uniform; second, cocoons gathered in the wild have usually had the pupa emerge from them before being discovered so the silk thread that makes up the cocoon has been torn into shorter lengths; and third, many wild cocoons are covered in a mineral layer that prevents attempts to reel from them long strands of silk. Thus, the only way to obtain silk suitable for spinning into textiles in areas where commercial silks are not cultivated

10664-740: The early center of the silk industry in America, when the Cheney Brothers became the first in the United States to properly raise silkworms on an industrial scale; today the Cheney Brothers Historic District showcases their former mills. With the mulberry tree craze of that decade, other smaller producers began raising silkworms. This economy particularly gained traction in the vicinity of Northampton, Massachusetts and its neighboring Williamsburg , where

10788-411: The emperors of China for their own use and gifts to others, but spread gradually through Chinese culture and trade both geographically and socially, and then to many regions of Asia . Because of its texture and lustre, silk rapidly became a popular luxury fabric in the many areas accessible to Chinese merchants. Silk was in great demand, and became a staple of pre- industrial international trade . Silk

10912-419: The epidermis begins to form a new cuticle. At the end of each instar, the larva moults , the old cuticle splits and the new cuticle expands, rapidly hardening and developing pigment. Development of butterfly wing patterns begins by the last larval instar. Caterpillars have short antennae and several simple eyes . The mouthparts are adapted for chewing with powerful mandibles and a pair of maxillae, each with

11036-741: The family Hesperiidae (skippers). Molecular clock estimates suggest that butterflies originated sometime in the Late Cretaceous , but only significantly diversified during the Cenozoic, with one study suggesting a North American origin for the group. The oldest American butterfly is the Late Eocene Prodryas persephone from the Florissant Fossil Beds , approximately 34   million years old. Butterflies are divided into seven families that contain

11160-409: The friction of their overlapping parts. The front two segments have a pair of spiracles which are used in respiration. The abdomen consists of ten segments and contains the gut and genital organs. The front eight segments have spiracles and the terminal segment is modified for reproduction. The male has a pair of clasping organs attached to a ring structure, and during copulation, a tubular structure

11284-500: The golden silk, and Eri are produced by silkworms that are native only to Assam. They have been reared since ancient times similar to other East and South-East Asian countries. Silk is produced year-round in Thailand by two types of silkworms, the cultured Bombycidae and wild Saturniidae. Most production is after the rice harvest in the southern and northeastern parts of the country. Women traditionally weave silk on hand looms and pass

11408-555: The grass was growing. The earliest Lepidoptera fossils date to the Triassic - Jurassic boundary, around 200   million years ago. Butterflies evolved from moths, so while the butterflies are monophyletic (forming a single clade ), the moths are not. The oldest known butterfly is Protocoeliades kristenseni from the Palaeocene aged Fur Formation of Denmark, approximately 55   million years old, which belongs to

11532-571: The great Mediterranean mercantile cities. Silk was produced in and exported from the province of Granada , Spain, especially the Alpujarras region, until the Moriscos , whose industry it was, were expelled from Granada in 1571. Since the 15th century, silk production in France has been centered around the city of Lyon where many mechanic tools for mass production were first introduced in

11656-1030: The laboratory it recovers within a few generation when allowed to breed freely. During mate selection, adult females do not innately avoid or learn to avoid siblings, implying that such detection may not be critical to reproductive fitness. Inbreeding may persist in B anynana because the probability of encountering close relatives is rare in nature; that is, movement ecology may mask the deleterious effect of inbreeding resulting in relaxation of selection for active inbreeding avoidance behaviors. Butterflies feed primarily on nectar from flowers. Some also derive nourishment from pollen , tree sap, rotting fruit, dung, decaying flesh, and dissolved minerals in wet sand or dirt. Butterflies are important as pollinators for some species of plants. In general, they do not carry as much pollen load as bees , but they are capable of moving pollen over greater distances. Flower constancy has been observed for at least one species of butterfly. Adult butterflies consume only liquids, ingested through

11780-557: The largest silk exporter in the world. This increase in exports was mostly due to the economic reforms during the Meiji period and the decline of the Qing dynasty in China, which led to rapid industrialization of Japan whilst the Chinese industries stagnated. During World War II , embargoes against Japan had led to adoption of synthetic materials such as nylon , which led to the decline of

11904-490: The larva and adult stages. The chrysalis generally refers to a butterfly pupa although the term may be misleading as there are some moths whose pupae resembles a chrysalis, e.g.: the plume winged moths of the family Pterophoridae and some geometrid moths. A cocoon is a silk case that the larvae of moths, and sometimes other insects, spin around the pupa. A cocoon is a casing spun of silk by many moths and caterpillars , and numerous other holometabolous insect larvae as

12028-460: The latter part of the 1st millennium BC, though China maintained its virtual monopoly over silk production for another thousand years. Several kinds of wild silk, produced by caterpillars other than the mulberry silkworm, have been known and spun in China , South Asia , and Europe since ancient times. However, the scale of production was always far smaller than for cultivated silks. There are several reasons for this: first, they differ from

12152-467: The lustrous quality of silk fabric. Aristotle wrote of Coa vestis , a wild silk textile from Kos . Sea silk from certain large sea shells was also valued. The Roman Empire knew of and traded in silk, and Chinese silk was the most highly priced luxury good imported by them. During the reign of emperor Tiberius , sumptuary laws were passed that forbade men from wearing silk garments, but these proved ineffectual. The Historia Augusta mentions that

12276-506: The majority of moths which fly by night, are often cryptically coloured (well camouflaged), and either hold their wings flat (touching the surface on which the moth is standing) or fold them closely over their bodies. Some day-flying moths, such as the hummingbird hawk-moth , are exceptions to these rules. Butterfly larvae , caterpillars , have a hard ( sclerotised ) head with strong mandibles used for cutting their food, most often leaves. They have cylindrical bodies, with ten segments to

12400-676: 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 ( bees , wasps , and ants ), silverfish , caddisflies , mayflies , thrips , leafhoppers , beetles , lacewings , fleas , flies , and midges . Other types of arthropods produce silk, most notably various arachnids , such as spiders . The word silk comes from Old English : sioloc , from Latin : sericum and Ancient Greek : σηρικός , romanized :  sērikós , "silken", ultimately from

12524-484: The most economically important of all lepidopterans. The silk moth is the only completely domesticated lepidopteran; it does not exist in the wild. Insects that pupate in a cocoon must escape from it, and they do this either by the pupa cutting its way out, or by secreting enzymes , sometimes called cocoonase , that soften the cocoon. Some cocoons are constructed with built-in lines of weakness along which they will tear easily from inside, or with exit holes that only allow

12648-401: The name is ancient, but modern Dutch and German use different words ( vlinder and Schmetterling ) and the common name often varies substantially between otherwise closely related languages. A possible source of the name is the bright yellow male of the brimstone ( Gonepteryx rhamni ); another is that butterflies were on the wing in meadows during the spring and summer butter season while

12772-488: The nickname "Silk City" as another major center of production in the United States. World War II interrupted the silk trade from Asia, and silk prices increased dramatically. U.S. industry began to look for substitutes, which led to the use of synthetics such as nylon . Synthetic silks have also been made from lyocell , a type of cellulose fiber, and are often difficult to distinguish from real silk (see spider silk for more on synthetic silks). In Terengganu , which

12896-422: The nineteenth and early twentieth centuries, Japanese exports competed directly with Chinese in the international market in such low value-added, labor-intensive products as raw silk. Between 1850 and 1930, raw silk ranked as the leading export for both countries, accounting for 20%–40% of Japan's total exports and 20%–30% of China's. Between the 1890s and the 1930s, Japanese silk exports quadrupled, making Japan

13020-470: The outside of caterpillars and the newly hatched fly larvae bore their way through the skin and feed in a similar way to the parasitoid wasp larvae. Predators of butterflies include ants, spiders, wasps, and birds. 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

13144-447: The outside of their cocoon in an attempt to disguise it from predators. Others spin their cocoon in a concealed location—on the underside of a leaf , in a crevice , down near the base of a tree trunk , suspended from a twig or concealed in the leaf litter . Contrary to popular belief, larvae do not completely liquify inside the cocoon. The silk in the cocoon of the silk moth can be unraveled to harvest silk fibre which makes this moth

13268-434: The possible presence of a suitable host. Prior to emergence, the adult inside the pupal exoskeleton is termed pharate . Once the pharate adult has eclosed from the pupa, the empty pupal exoskeleton is called an exuvia ; in most hymenopterans (ants, bees and wasps) the exuvia is so thin and membranous that it becomes "crumpled" as it is shed. Measuring the timing of this emergence is of interest to chronobiologists because

13392-531: The present day, sometimes spinning wild silk. King James I introduced silk-growing to the British colonies in America around 1619, ostensibly to discourage tobacco planting. The Shakers in Kentucky adopted the practice. The history of industrial silk in the United States is largely tied to several smaller urban centers in the Northeast region. Beginning in the 1830s, Manchester, Connecticut emerged as

13516-529: The proboscis. They sip water from damp patches for hydration and feed on nectar from flowers, from which they obtain sugars for energy, and sodium and other minerals vital for reproduction. Several species of butterflies need more sodium than that provided by nectar and are attracted by sodium in salt; they sometimes land on people, attracted by the salt in human sweat. Some butterflies also visit dung and scavenge rotting fruit or carcasses to obtain minerals and nutrients. In many species, this mud-puddling behaviour

13640-400: The process is regulated by circadian clocks in many species, necessitating different assays to measure eclosion timing. In a few taxa of the Lepidoptera, especially Heliconius , pupal mating is an extreme form of reproductive strategy in which the adult male mates with a female pupa about to emerge, or with the newly moulted female; this is accompanied by other actions such as capping of

13764-407: The pupal appendages are free or attached to the body, the pupae can be classified as one of three types: A chrysalis ( Latin : chrysallis , from Ancient Greek : χρυσαλλίς , chrysallís , plural: chrysalides , also known as an aurelia ) or nympha is the pupal stage of butterflies . The term is derived from the metallic–gold coloration found in the pupae of many butterflies, referred to by

13888-431: The quest for a suitable pupation site, often the underside of a leaf or other concealed location. There it spins a button of silk which it uses to fasten its body to the surface and moults for a final time. While some caterpillars spin a cocoon to protect the pupa, most species do not. The naked pupa, often known as a chrysalis, usually hangs head down from the cremaster, a spiny pad at the posterior end, but in some species

14012-399: The reasoning behind the prohibition lies in avoiding clothing for men that can be considered feminine or extravagant. There are disputes regarding the amount of silk a fabric can consist of (e.g., whether a small decorative silk piece on a cotton caftan is permissible or not) for it to be lawful for men to wear, but the dominant opinion of most Muslim scholars is that the wearing of silk by men

14136-466: The region: mulberry, endi, and tassar. Bengali silk was a major item of international trade for centuries. It was known as Ganges silk in medieval Europe. Bengal was the leading exporter of silk between the 16th and 19th centuries. The 7th century CE murals of Afrasiyab in Samarkand , Sogdiana , show a Chinese Embassy carrying silk and a string of silkworm cocoons to the local Sogdian ruler. In

14260-443: The reproductive system of the female with the sphragis , denying access to other males, or by exuding an anti-aphrodisiac pheromone. Pupae are usually immobile and are largely defenseless. To overcome this, pupae often are covered with a cocoon, conceal themselves in the environment, or form underground. Some species of Lycaenid butterflies are protected in their pupal stage by ants. Another means of defense by pupae of other species

14384-748: The silkworms on mulberry leaves. Once the worms start pupating in their cocoons, these are dissolved in boiling water in order for individual long fibres to be extracted and fed into the spinning reel. To produce 1 kg of silk, 104 kg of mulberry leaves must be eaten by 3000 silkworms. It takes about 5000 silkworms to make a pure silk kimono . The major silk producers are China (54%) and India (14%). Other statistics: Production in Int $ 1000 have been calculated based on 1999–2001 international prices Source: Food And Agricultural Organization of United Nations: Economic And Social Department: The Statistical Division The environmental impact of silk production

14508-400: The skill on to their daughters, as weaving is considered to be a sign of maturity and eligibility for marriage. Thai silk textiles often use complicated patterns in various colours and styles. Most regions of Thailand have their own typical silks. A single thread filament is too thin to use on its own so women combine many threads to produce a thicker, usable fiber. They do this by hand-reeling

14632-569: The third-century emperor Elagabalus was the first Roman to wear garments of pure silk, whereas it had been customary to wear fabrics of silk/cotton or silk/linen blends. Despite the popularity of silk, the secret of silk-making only reached Europe around AD 550, via the Byzantine Empire . Contemporary accounts state that monks working for the emperor Justinian I smuggled silkworm eggs to Constantinople from China inside hollow canes. All top-quality looms and weavers were located inside

14756-435: The threads onto a wooden spindle to produce a uniform strand of raw silk. The process takes around 40 hours to produce a half kilogram of silk. Many local operations use a reeling machine for this task, but some silk threads are still hand-reeled. The difference is that hand-reeled threads produce three grades of silk: two fine grades that are ideal for lightweight fabrics, and a thick grade for heavier material. The silk fabric

14880-727: The time of the Indus Valley civilisation (now in Pakistan and India) dating between 2450 BC and 2000 BC. Shelagh Vainker, a silk expert at the Ashmolean Museum in Oxford, who sees evidence for silk production in China "significantly earlier" than 2500–2000 BC, suggests, "people of the Indus civilization either harvested silkworm cocoons or traded with people who did, and that they knew a considerable amount about silk." India

15004-685: Was also used as a surface for writing, especially during the Warring States period (475–221 BCE). The fabric was light, it survived the damp climate of the Yangtze region, absorbed ink well, and provided a white background for the text. In July 2007, archaeologists discovered intricately woven and dyed silk textiles in a tomb in Jiangxi province, dated to the Eastern Zhou dynasty roughly 2,500 years ago. Although historians have suspected

15128-830: Was built in Congleton . These three towns remained the centre of the English silk throwing industry until silk throwing was replaced by silk waste spinning . British enterprise also established silk filature in Cyprus in 1928. In England in the mid-20th century, raw silk was produced at Lullingstone Castle in Kent. Silkworms were raised and reeled under the direction of Zoe Lady Hart Dyke , later moving to Ayot St Lawrence in Hertfordshire in 1956. During World War II , supplies of silk for UK parachute manufacture were secured from

15252-470: Was by tedious and labor-intensive carding . Some natural silk structures have been used without being unwound or spun. Spider webs were used as a wound dressing in ancient Greece and Rome, and as a base for painting from the 16th century. Caterpillar nests were pasted together to make a fabric in the Aztec Empire . Commercial silks originate from reared silkworm pupae, which are bred to produce

15376-619: Was sold in a large market fair in the port of Reggio Calabria , to Spanish, Venetian, Genovese, and Dutch merchants. Catanzaro became the lace capital of the world with a large silkworm breeding facility that produced all the laces and linens used in the Vatican. The city was world-famous for its fine fabrication of silks, velvets, damasks, and brocades. Another notable center was the Italian city-state of Lucca which largely financed itself through silk-production and silk-trading, beginning in

#669330