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131-518: Halpe homolea , the Indian ace or Ceylon ace , is a butterfly belonging to the family Hesperiidae . Male. Upperside blackish-brown. Forewing with five or six semi-hyaline spots, one or the other of them often absent, one inside the upper end of the cell, two obliquely, in the disc, near the bases of the median interspaces, these spots are sometimes quadrate, sometimes oblong, and sometimes quite round and small, and two small sub-apical spots, sometimes

262-637: 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

393-458: A forest or wild grasslands with native pollinators near agricultural crops, such as apples, almonds or coffee can improve their yield by about 20%. The benefits of native pollinators may result in forest owners demanding payment for their contribution in the improved crop results – a simple example of the economic value of ecological services. Farmers can also raise native crops in order to promote native bee pollinator species as shown with

524-500: A bee that collects oil from Diascia capsularis , which have long spur lengths that are selected for in order to deposit pollen on the oil-collecting bee, which in turn selects for even longer legs in R. neliana and again longer spur length in D. capsularis is selected for, thus, continually driving each other's evolution. The most essential staple food crops on the planet, like wheat , maize , rice , soybeans and sorghum are wind pollinated or self pollinating. When considering

655-493: 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

786-570: 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

917-1129: A certain frequency in order to cause pollen to be released from the anthers . In zoophily , pollination is performed by vertebrates such as birds and bats , particularly, hummingbirds , sunbirds , spiderhunters , honeyeaters , and fruit bats . Ornithophily or bird pollination is the pollination of flowering plants by birds. Chiropterophily or bat pollination is the pollination of flowering plants by bats. Plants adapted to use bats or moths as pollinators typically have white petals, strong scent and flower at night, whereas plants that use birds as pollinators tend to produce copious nectar and have red petals. Mammals are not generally thought of as pollinators, but some rodents, bats and marsupials are significant pollinators and some even specialise in such activities. In South Africa certain species of Protea (in particular Protea humiflora , P. amplexicaulis , P. subulifolia , P. decurrens and P. cordata ) are adapted to pollination by rodents (particularly Cape Spiny Mouse , Acomys subspinosus ) and elephant shrews ( Elephantulus species). The flowers are borne near

1048-399: A commercial crop can be produced without cross-pollination, though cross-pollination usually gives a better crop. Apples are considered self-incompatible , because a commercial crop must be cross-pollinated. Many commercial fruit tree varieties are grafted clones , genetically identical. An orchard block of apples of one variety is genetically a single plant. Many growers now consider this

1179-417: 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

1310-442: A critical point. This simultaneous collapse occurs, because pollinator species depend on each other when surviving under difficult conditions. Such a community-wide collapse, involving many pollinator species, can occur suddenly when increasingly harsh conditions pass a critical point and recovery from such a collapse might not be easy. The improvement in conditions needed for pollinators to recover, could be substantially larger than

1441-488: A decline in winter managed beehives, which has reached an unprecedented rate of colony losses at near 30%. At present, there is an enormous demand for beehive rentals that cannot always be met. There is a clear need across the agricultural industry for a management tool to draw pollinators into cultivations and encourage them to preferentially visit and pollinate the flowering crop. By attracting pollinators like honey bees and increasing their foraging behavior, particularly in

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1572-435: A discal, outwardly curved series of more or less obscure, ochreous-white spots from the costa to above the sub-median vein. Cilia of both wings whitish, with brown spots opposite the vein ends; all these markings very variable, in some examples the basal greyish-ochreous suffusion is very dull and indistinct, in some it is entirely absent, and in some examples all the spots on both wings are almost entirely absent. Antennte black,

1703-576: 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

1834-444: 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

1965-407: A focus on neonicotinoids effects on honey bee populations. Neonicotinoids insecticides have been used due to its low mammalian toxicity, target specificity, low application rates, and broad spectrum activity. However, the insecticides are able to make its way throughout the plant, which includes the pollen and nectar. Due to this, it has been shown to effect on the nervous system and colony relations in

2096-439: A good pollenizer is a plant that provides compatible, viable and plentiful pollen and blooms at the same time as the plant that is to be pollinated or has pollen that can be stored and used when needed to pollinate the desired flowers. Hybridization is effective pollination between flowers of different species , or between different breeding lines or populations. see also Heterosis . Peaches are considered self-fertile because

2227-606: 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

2358-486: A lack of animal food and of predation pressure, might therefore favour reptiles becoming more herbivorous and more inclined to feed on pollen and nectar. Most species of lizards in the families that seem to be significant in pollination seem to carry pollen only incidentally, especially the larger species such as Varanidae and Iguanidae , but especially several species of the Gekkonidae are active pollinators, and so

2489-508: 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

2620-416: 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

2751-404: A little paler and ochreous-tinted. Forewing with a dull ochreous-white streak below the basal half of the costa, the spots as above, but all tinted with ochreous, and a series of sub-marginal, more densely ochreous-tinted spots, one in each interspace, which become obsolete hindwards. Hindwing with the basal half of the wing smeared with dull greyish-ochreous, caused by minute scaling of that colour;

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2882-547: 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

3013-474: A mistake. One means of correcting this mistake is to graft a limb of an appropriate pollenizer (generally a variety of crabapple ) every six trees or so. The first fossil record for abiotic pollination is from fern -like plants in the late Carboniferous period. Gymnosperms show evidence for biotic pollination as early as the Triassic period. Many fossilized pollen grains show characteristics similar to

3144-452: 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

3275-468: A pollen grain lands close enough to the tip of an ovule, it is drawn in through the micropyle ( a pore in the integuments covering the tip of the ovule) often by means of a drop of liquid known as a pollination drop. The pollen enters a pollen chamber close to the nucellus, and there it may wait for a year before it germinates and forms a pollen tube that grows through the wall of the megasporangium (=nucellus) where fertilisation takes place. During this time,

3406-658: 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

3537-412: 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

3668-435: 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

3799-410: A third minute spot close to the costa; in some examples (perara) all the spots are absent, except the two discal spots which are small and round, but the genitalia of all of them are said to be alike, showing them to be of one variable species. Hindwing without markings. Cilia chequered brown and ochreous-grey on the forewing, whitish on the hindwing, with some small brown marks at the vein ends. Underside

3930-410: 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

4061-541: 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

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4192-470: 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

4323-486: 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

4454-437: 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

4585-422: 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

4716-511: A wide variety of agricultural crops, and ranks as the most frequent single species of pollinator for crops worldwide. Since the early 1900s, beekeepers in the United States started renting out their colonies to farmers to increase the farmer's crop yields, earning additional revenue from providing privatized pollination . As of 2016, 41% of an average US beekeeper's revenue comes from providing such pollination service to farmers, making it

4847-450: 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

4978-622: Is also estimated that about 42% of flowering plants have a mixed mating system in nature. In the most common kind of mixed mating system, individual plants produce a single type of flower and fruits may contain self-pollinated, out-crossed or a mixture of progeny types. Pollination also requires consideration of pollenizers , the plants that serve as the pollen source for other plants. Some plants are self-compatible ( self-fertile ) and can pollinate and fertilize themselves. Other plants have chemical or physical barriers to self-pollination . In agriculture and horticulture pollination management,

5109-431: Is an important pollinator for alfalfa seed in western United States and Canada. Bumblebees are increasingly raised and used extensively for greenhouse tomatoes and other crops. The ecological and financial importance of natural pollination by insects to agricultural crops , improving their quality and quantity, becomes more and more appreciated and has given rise to new financial opportunities. The vicinity of

5240-519: Is at least one species of the Lacertidae , Podarcis lilfordi , which pollinates various species, but in particular is the major pollinator of Euphorbia dendroides on various Mediterranean islands. Abiotic pollination uses nonliving methods such as wind and water to move pollen from one flower to another. This allows the plant to spend energy directly on pollen rather than on attracting pollinators with flowers and nectar . Pollination by wind

5371-417: Is believed that if pollinator populations continue to decrease these deficiencies will become even more prominent. Wild pollinators often visit a large number of plant species and plants are visited by a large number of pollinator species. All these relations together form a network of interactions between plants and pollinators. Surprising similarities were found in the structure of networks consisting out of

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5502-452: Is causing an acceleration of the loss of pollinators. Changes in land use, harmful pesticides, and advancing climate change threaten wild pollinators, key insect species that increase yields of three-fourths of crop varieties and are critical to growing healthy foods. In some situations, farmers or horticulturists may aim to restrict natural pollination to only permit breeding with the preferred individuals plants. This may be achieved through

5633-424: Is contained within the resistant. The pollen grains are dispersed by the wind to the female, ovulate cone that is made up of many overlapping scales (sporophylls, and thus megasporophylls), each protecting two ovules, each of which consists of a megasporangium (the nucellus) wrapped in two layers of tissue, the integument and the cupule, that were derived from highly modified branches of ancestral gymnosperms. When

5764-437: Is dependent on fertilisation: the result of pollination. The study of pollination by insects is known as anthecology . There are also studies in economics that look at the positives and negatives of pollination, focused on bees, and how the process affects the pollinators themselves. Pollen germination has three stages; hydration, activation and pollen tube emergence. The pollen grain is severely dehydrated so that its mass

5895-458: 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

6026-403: 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

6157-410: 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,

6288-451: 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

6419-634: Is more common amongst abiotic pollination. Some 98% of abiotic pollination is anemophily , i.e., pollination by wind. This probably arose from insect pollination (entomophily), most likely due to changes in the environment or the availability of pollinators. The transfer of pollen is more efficient than previously thought; wind pollinated plants have developed to have specific heights, in addition to specific floral, stamen and stigma positions that promote effective pollen dispersal and transfer. Pollination by water, hydrophily , uses water to transport pollen, sometimes as whole anthers; these can travel across

6550-581: 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

6681-498: Is necessary in producing fruit with nutritional value and various flavors. Crops that do not depend on animals for pollination but on the wind or self-pollination, like corn and potatoes, have doubled in production and make up a large part of the human diet but do not provide the micronutrients that are needed. The essential nutrients that are necessary in the human diet are present in plants that rely on animal pollinators. There have been issues in vitamin and mineral deficiencies and it

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6812-412: Is perhaps the most well known) has been noticed in recent years. These loss of pollinators have caused a disturbance in early plant regeneration processes such as seed dispersal and pollination. Early processes of plant regeneration greatly depend on plant-animal interactions and because these interactions are interrupted, biodiversity and ecosystem functioning are threatened. Pollination by animals aids in

6943-408: Is reduced, enabling it to be more easily transported from flower to flower. Germination only takes place after rehydration, ensuring that premature germination does not take place in the anther. Hydration allows the plasma membrane of the pollen grain to reform into its normal bilayer organization providing an effective osmotic membrane. Activation involves the development of actin filaments throughout

7074-465: 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

7205-698: 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

7336-405: 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

7467-408: Is the decline of biodiversity through the deaths of commercial and wild bees. Despite losing about a third of their workforce every year, beekeepers continue to rent out their bees to almond farms due to the high pay from the almond industry. In 2016, a colony rented out for almond pollination gave beekeepers an income of $ 165 per colony rented, around three times from average of other crops that use

7598-421: Is the fact that in open land the butterflies would be exposed to desiccation and predation. These open regions are caused by habitat destruction like logging for timber, livestock grazing, and firewood collection. Due to this destruction, butterfly species' diversity can decrease and it is known that there is a correlation in butterfly diversity and plant diversity. Besides the imbalance of the ecosystem caused by

7729-428: Is used by a small percentage of plants. Heavy rain discourages insect pollination and damages unprotected flowers, but can itself disperse pollen of suitably adapted plants, such as Ranunculus flammula , Narthecium ossifragum , and Caltha palustris . In these plants, excess rain drains allowing the floating pollen to come in contact with the stigma. In some orchids ombrophily occurs, and rain water splashes cause

7860-461: 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,

7991-479: 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

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8122-474: 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

8253-455: 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

8384-448: The combine harvesters follow the wheat harvest from Texas to Manitoba , beekeepers follow the bloom from south to north, to provide pollination for many different crops. In America, bees are brought to commercial plantings of cucumbers , squash , melons , strawberries , and many other crops. Honey bees are not the only managed pollinators: a few other species of bees are also raised as pollinators. The alfalfa leafcutter bee

8515-504: The dinosaur era. Insect pollinators such as honey bees ( Apis spp.), bumblebees ( Bombus spp.), and butterflies (e.g., Thymelicus flavus ) have been observed to engage in flower constancy , which means they are more likely to transfer pollen to other conspecific plants. This can be beneficial for the pollinators, as flower constancy prevents the loss of pollen during interspecific flights and pollinators from clogging stigmas with pollen of other flower species. It also improves

8646-540: 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

8777-402: 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

8908-600: 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

9039-407: The pollen from one flower to another. Abiotic pollination relies on wind, water or even rain. Adding natural habitat areas into farm systems generally improves pollination, as farms that are closer to natural habitat have higher crop yield because they are visited by more pollinators. About 80% of angiosperms rely on biotic pollination. (also called pollen vectors): organisms that carry or move

9170-540: 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

9301-472: The United States, an $ 11 billion industry based almost exclusively in the state of California, is heavily dependent on imported honeybees for pollination of almond trees. Almond industry uses up to 82% of the services in the pollination market. Each February, around 60% of the all bee colonies in the US are moved to California's Central Valley . Over the past decade, beekeepers across the US have reported that

9432-430: 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

9563-405: 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

9694-502: 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

9825-433: 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

9956-467: 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

10087-434: 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

10218-785: The anther cap to be removed, allowing for the pollen to be exposed. After exposure, raindrops causes the pollen to be shot upward, when the stipe pulls them back, and then fall into the cavity of the stigma. Thus, for the orchid Acampe rigida , this allows the plant to self-pollinate, which is useful when biotic pollinators in the environment have decreased. It is possible for a plant to have varying pollination methods, including both biotic and abiotic pollination. The orchid Oeceoclades maculata uses both rain and butterflies, depending on its environmental conditions. Pollination can be accomplished by cross-pollination or by self-pollination : An estimated 48.7% of plant species are either dioecious or self-incompatible obligate out-crossers. It

10349-436: The area is forage poor or even deadly to bees for the rest of the season. The other trend is the decline of pollinator populations , due to pesticide misuse and overuse, new diseases and parasites of bees, clearcut logging , decline of beekeeping, suburban development, removal of hedges and other habitat from farms , and public concern about bees. Widespread aerial spraying for mosquitoes due to West Nile fears

10480-524: The bees in the US as mentioned above, will be mixed with bees from thousands of other hives provided by different beekeepers, making them exponentially susceptible to diseases and mites that any of them could be carrying. The deaths do not stop at commercial honeybees as there is evidence of significant pathogen spillover to other pollinators including wild bumble bees, infecting up to 35-100% of wild bees within 2 km radius of commercial pollination. The negative externality of private pollination services

10611-438: The beginning of the mutualism between hymenopterans and angiosperms. Bees provide a good example of the mutualism that exists between hymenopterans and angiosperms. Flowers provide bees with nectar (an energy source) and pollen (a source of protein). When bees go from flower to flower collecting pollen they are also depositing pollen grains onto the flowers, thus pollinating them. While pollen and nectar, in most cases, are

10742-430: The biggest proportion of their income, with the rest coming from sales of honey, beeswax, government subsidy, etc. This is an example of how a positive externality , pollination of crops from beekeeping and honey-making, was successfully accounted for and incorporated into the overall market for agriculture. On top of assisting food production, pollination service provide beneficial spillovers as bees germinate not only

10873-426: The biotically dispersed pollen today. Furthermore, the gut contents, wing structures, and mouthpart morphology of fossilized beetles and flies suggest that they acted as early pollinators. The association between beetles and angiosperms during the early Cretaceous period led to parallel radiations of angiosperms and insects into the late Cretaceous. The evolution of nectaries in late Cretaceous flowers signals

11004-658: 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

11135-436: The case of neonicotinoids that harm bee colonies. Many researchers believe it is the synergistic effects of these factors which are ultimately detrimental to pollinator populations. In the agriculture industry, climate change is causing a "pollinator crisis". This crisis is affecting the production of crops, and the relating costs, due to a decrease in pollination processes. This disturbance can be phenological or spatial. In

11266-403: The center of large plots, we can increase grower returns and optimize yield from their plantings. ISCA Technologies, from Riverside, California , created a semiochemical formulation called SPLAT Bloom, that modifies the behavior of honey bees, inciting them to visit flowers in every portion of the field. Loss of pollinators, also known as pollinator decline (of which colony collapse disorder

11397-496: The colonies affected and the colonies themselves. Pollution and pesticides are detrimental to the health of the bees and their colonies as the bees' ability to pollinate and return to their colonies are great greatly compromised. Moreover, California's Central Valley is determined by the World Health Organization as the location of country's worst air pollution . Almond pollinating bees, approximately 60% of

11528-465: The conversion to secondary forest habitat. Defaunation of frugivores is also an important driver. These alterations are especially harmful due to the sensitivity of the pollination process of plants. Research on tropical palms found that defaunation has caused a decline in seed dispersal, which causes a decrease in genetic variability in this species. Habitat destruction such as fragmentation and selective logging remove areas that are most optimal for

11659-528: The crops, but also other plants around the area that they are set loose to pollinate, increasing biodiversity for the local ecosystem . There is even further spillover as biodiversity increases ecosystem resistance for wildlife and crops. Due to their role of pollination in crop production, commercial honeybees are considered to be livestock by the US Department of Agriculture . The impact of pollination varies by crop. For example, almond production in

11790-515: The cytoplasm of the cell, which eventually become concentrated at the point from which the pollen tube will emerge. Hydration and activation continue as the pollen tube begins to grow. In conifers, the reproductive structures are borne on cones. The cones are either pollen cones (male) or ovulate cones (female), but some species are monoecious and others dioecious . A pollen cone contains hundreds of microsporangia carried on (or borne on) reproductive structures called sporophylls. Spore mother cells in

11921-502: The decline in pollinators, it may jeopardise food security . Pollination is necessary for plants to continue their populations and 3/4 of the plant species that contribute to the world's food supply are plants that require pollinators. Insect pollinators, like bees, are large contributors to crop production, over 200 billion dollars worth of crop species are pollinated by these insects. Pollinators are also essential because they improve crop quality and increase genetic diversity, which

12052-441: 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

12183-458: The different types of pollinators, which removes pollinators food resources, nesting sites, and leads to isolation of populations. The effect of pesticides on pollinators has been debated because it is difficult to determine that a single pesticide is the cause as opposed to a mixture or other threats. Whether exposure alone causes damage, or if the duration and potency are also factors is unknown. However, insecticides have negative effects, as in

12314-419: 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

12445-741: 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

12576-526: The female gametophytes, which are very strongly reduced, each consisting only of a few cells, one of which is the egg. When a pollen grain adheres to the stigma of a carpel it germinates, developing a pollen tube that grows through the tissues of the style, entering the ovule through the micropyle. When the tube reaches the egg sac, two sperm cells pass through it into the female gametophyte and fertilisation takes place. Pollination may be biotic or abiotic. Biotic pollination relies on living pollinators to move

12707-570: The first case, species that normally occur in similar seasons or time cycles, now have different responses to environmental changes and therefore no longer interact. For example, a tree may flower sooner than usual, while the pollinator may reproduce later in the year and therefore the two species no longer coincide in time. Spatial disturbances occur when two species that would normally share the same distribution now respond differently to climate change and are shifting to different regions. The most known and understood pollinator, bees, have been used as

12838-409: 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

12969-507: The genetic variability and diversity within plants because it allows for out-crossing instead for self-crossing. Without this genetic diversity there would be a lack of traits for natural selection to act on for the survival of the plant species. Seed dispersal is also important for plant fitness because it allows plants the ability to expand their populations. More than that, it permits plants to escape environments that have changed and have become difficult to reside in. All of these factors show

13100-500: 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

13231-556: The ground, are yeasty smelling, not colourful, and sunbirds reject the nectar with its high xylose content. The mice apparently can digest the xylose and they eat large quantities of the pollen. In Australia pollination by flying, gliding and earthbound mammals has been demonstrated. Reptile pollinators are known, but they form a minority in most ecological situations. They are most frequent and most ecologically significant in island systems, where insect and sometimes also bird populations may be unstable and less species-rich. Adaptation to

13362-401: The honey bee populations. Butterflies too have suffered due to these modifications. Butterflies are helpful ecological indicators since they are sensitive to changes within the environment like the season, altitude, and above all, human impact on the environment . Butterfly populations were higher within the natural forest and were lower in open land. The reason for the difference in density

13493-672: The importance of pollinators for plants, which are a significant part of the foundation for a stable ecosystem. If only a few species of plants depended on Loss of pollinators is especially devastating because there are so many plant species rely on them. More than 87.5% of angiosperms , over 75% of tropical tree species, and 30-40% of tree species in temperate regions depend on pollination and seed dispersal. Factors that contribute to pollinator decline include habitat destruction , pesticide , parasitism / diseases , and climate change . The more destructive forms of human disturbances are land use changes such as fragmentation, selective logging, and

13624-433: The improvement needed to return to conditions at which the pollinator community collapsed. While there are 200,000 - 350,000 different species of animals that help pollination, honeybees are responsible for majority of the pollination for consumed crops, providing between $ 235 and $ 577 US billion of benefits to global food production. The western honey bee ( Apis mellifera L.) provides highly valued pollination services for

13755-421: The interactions between plants and pollinators. This structure was found to be similar in very different ecosystems on different continents, consisting of entirely different species. The structure of plant-pollinator networks may have large consequences for the way in which pollinator communities respond to increasingly harsh conditions. Mathematical models, examining the consequences of this network structure for

13886-1030: 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

14017-506: 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

14148-470: The megasporangium wall and delivers the sperm cells to the female gametophyte inside. Fertilisation takes place when the nucleus of one of the sperm cells enters the egg cell in the megagametophyte's archegonium. In flowering plants, the anthers of the flower produce microspores by meiosis. These undergo mitosis to form male gametophytes, each of which contains two haploid cells. Meanwhile, the ovules produce megaspores by meiosis, further division of these form

14279-476: The megaspore mother cell divides by meiosis to form four haploid cells, three of which degenerate. The surviving one develops as a megaspore and divides repeatedly to form an immature female gametophyte (egg sac). Two or three archegonia containing an egg then develop inside the gametophyte. Meanwhile, in the spring of the second year two sperm cells are produced by mitosis of the body cell of the male gametophyte. The pollen tube elongates and pierces and grows through

14410-412: The microsporangia divide by meiosis to form haploid microspores that develop further by two mitotic divisions into immature male gametophytes (pollen grains). The four resulting cells consist of a large tube cell that forms the pollen tube , a generative cell that will produce two sperm by mitosis , and two prothallial cells that degenerate. These cells comprise a very reduced microgametophyte , that

14541-402: The mortality rate of their bee colonies has stayed constant at about 30% every year, making the deaths an expected cost of business for the beekeepers. While the exact cause of this phenomenon is unknown, according to the US Department of Agriculture Colony Collapse Disorder Progress Report it can be traced to factors such as pollution, pesticides, and pathogens from evidences found in areas of

14672-430: The most frequent visitors, these include monkeys, lemurs, squirrels, rodents and possums. Entomophily , pollination by insects , often occurs on plants that have developed colored petals and a strong scent to attract insects such as bees, wasps, and occasionally ants ( Hymenoptera ), beetles ( Coleoptera ), moths and butterflies ( Lepidoptera ), and flies ( Diptera ). The existence of insect pollination dates back to

14803-479: The most notable reward attained from flowers, bees also visit flowers for other resources such as oil, fragrance, resin and even waxes. It has been estimated that bees originated with the origin or diversification of angiosperms . In addition, cases of coevolution between bee species and flowering plants have been illustrated by specialized adaptations. For example, long legs are selected for in Rediviva neliana ,

14934-401: 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

15065-676: The native sweat bees L. vierecki in Delaware and L. leucozonium in southwest Virginia. The American Institute of Biological Sciences reports that native insect pollination saves the United States agricultural economy nearly an estimated $ 3.1 billion annually through natural crop production; pollination produces some $ 40 billion worth of products annually in the United States alone. Pollination of food crops has become an environmental issue , due to two trends. The trend to monoculture means that greater concentrations of pollinators are needed at bloom time than ever before, yet

15196-456: 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. Pollination In angiosperms , after the pollen grain ( gametophyte ) has landed on the stigma , it germinates and develops a pollen tube which grows down the style until it reaches an ovary . Its two gametes travel down

15327-403: The ovule is not contained in a carpel, but exposed on the surface of a dedicated support organ, such as the scale of a cone, so that the penetration of carpel tissue is unnecessary. Details of the process vary according to the division of gymnosperms in question. Two main modes of fertilisation are found in gymnosperms: cycads and Ginkgo have motile sperm that swim directly to the egg inside

15458-463: The ovule, whereas conifers and gnetophytes have sperm that are unable to swim but are conveyed to the egg along a pollen tube. The study of pollination spans many disciplines, such as botany , horticulture , entomology , and ecology . The pollination process as an interaction between flower and pollen vector was first addressed in the 18th century by Christian Konrad Sprengel . It is important in horticulture and agriculture , because fruiting

15589-413: The pollen grains from the anther of one flower to the receptive part of the carpel or pistil (stigma) of another. Between 100,000 and 200,000 species of animal act as pollinators of the world's 250,000 species of flowering plant. The majority of these pollinators are insects , but about 1,500 species of birds and mammals visit flowers and may transfer pollen between them. Besides birds and bats which are

15720-399: The pollination season were too short. Some flowers have specialized mechanisms to trap pollinators to increase effectiveness, attach pollen to specific body parts (as happens in many orchid and Asclepias species ), or require specialized behaviors or morphology in order to extract pollen or nectar. One such syndrome is " buzz pollination " (or "sonication"), where a bee must vibrate at

15851-545: The prime example of the decline in pollinators. Bees are essential in the pollination of agricultural crops and wild plants and are one of the main insects that perform this task. Out of the bees species, the honey bee or Apis mellifera has been studied the most and in the United States, there has been a loss of 59% of colonies from 1947 to 2005. The decrease in populations of the honey bee have been attributed to pesticides, genetically modified crops, fragmentation, parasites and diseases that have been introduced. There has been

15982-1128: The probability that the pollinator will find productive flowers easily accessible and recognisable by familiar clues. The primary insect pollinators are hymenopterans , mostly bees , but also including sawflies , ants , and many species of wasps. Many flowers attract pollinators by odor. For example, orchid bee species such as Euglossa cordata are attracted to orchids this way, and it has been suggested that some orchid species intoxicate bees during visits which can last up to 90 minutes. However, in general, plants that rely on pollen vectors tend to be adapted to their particular type of vector, for example day-pollinated species tend to be brightly coloured and have little odor, but if they are pollinated largely by birds or specialist mammals, they tend to be larger and have larger nectar rewards than species that are strictly insect-pollinated. Night-blooming flowers have little color, but are often very aromatic. Plants with vertebrate pollinators also tend to spread their rewards over longer periods, having long flowering seasons; their specialist pollinators would be likely to starve if

16113-529: 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

16244-431: 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

16375-443: The shaft spotted with ochreous-white un the uuderside, club with an orange tip; palpi, head and body blackish-brown, palpi beneath grey, pectus and abdomen whitish; legs dull pale red. Female like the male, usually somewhat paler in colour, the spots on the forewing a little larger. This Hesperiinae -related article is a stub . You can help Misplaced Pages by expanding it . Butterfly Butterflies are winged insects from

16506-426: The stability of pollinator communities suggest that the specific way in which plant-pollinator networks are organized minimizes competition between pollinators and may even lead to strong indirect facilitation between pollinators when conditions are harsh. This means that pollinator species together can survive under harsh conditions. But it also means that pollinator species collapse simultaneously when conditions pass

16637-437: The surface of the water to carry dry pollen from one flower to another. In Vallisneria spiralis , an unopened male flower floats to the surface of the water, and, upon reaching the surface, opens up and the fertile anthers project forward. The female flower, also floating, has its stigma protected from the water, while its sepals are slightly depressed into the water, allowing the male flowers to tumble in. Rain pollination

16768-469: The top 15 crops contributing to the human diet globally in 2013, slightly over 10% of the total human diet of plant crops (211 out of 1916 kcal/person/day) is dependent upon insect pollination. Pollination management is a branch of agriculture that seeks to protect and enhance present pollinators and often involves the culture and addition of pollinators in monoculture situations, such as commercial fruit orchards . The largest managed pollination event in

16899-460: The tube to where the gametophyte(s) containing the female gametes are held within the carpel . After entering an ovule through the micropyle , one male nucleus fuses with the polar bodies to produce the endosperm tissues , while the other fuses with the egg cell to produce the embryo . Hence the term: " double fertilisation ". This process would result in the production of a seed, made of both nutritious tissues and embryo. In gymnosperms ,

17030-415: The use of pollination bags . In some instances growers' demand for beehives far exceeds the available supply. The number of managed beehives in the US has steadily declined from close to 6 million after WWII, to less than 2.5 million today. In contrast, the area dedicated to growing bee-pollinated crops has grown over 300% in the same time period. Additionally, in the past five years there has been

17161-484: The world is in California almond orchards, where nearly half (about one million hives ) of the US honey bees are trucked to the almond orchards each spring. New York 's apple crop requires about 30,000 hives; Maine 's blueberry crop uses about 50,000 hives each year. The US solution to the pollinator shortage, so far, has been for commercial beekeepers to become pollination contractors and to migrate. Just as

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