Pollen is a powdery substance produced by most types of flowers of seed plants for the purpose of sexual reproduction. It consists of pollen grains (highly reduced microgametophytes ), which produce male gametes (sperm cells).
73-521: Amydetinae Cheguevariinae Chespiritoinae Cyphonocerinae Lamprohizinae Lampyrinae Luciolinae Ototretinae Photurinae Psilocladinae Pterotinae Genera incertae sedis : Anadrilus Kirsch, 1875 Araucariocladus Silveira and Mermudes, 2017 Crassitarsus Martin, 2019 Lamprigera Motschulsky, 1853 Oculogryphus Jeng, Engel, and Yang, 2007 Photoctus McDermott, 1961 Pollaclasis Newman, 1838 The Lampyridae are
146-501: A family of elateroid beetles with more than 2,000 described species, many of which are light-emitting . They are soft-bodied beetles commonly called fireflies , lightning bugs , or glowworms for their conspicuous production of light, mainly during twilight , to attract mates. Light production in the Lampyridae is thought to have originated as a warning signal that the larvae were distasteful. This ability to create light
219-771: A 54% increased chance of asthma attacks when exposed to pollen. The number of people in the United States affected by hay fever is between 20 and 40 million, including around 6.1 million children and such allergy has proven to be the most frequent allergic response in the nation. Hay fever affects about 20% of Canadians and the prevalence is increasing. There are certain evidential suggestions pointing out hay fever and similar allergies to be of hereditary origin . Individuals who suffer from eczema or are asthmatic tend to be more susceptible to developing long-term hay fever. Since 1990, pollen seasons have gotten longer and more pollen-filled, and climate change
292-409: A burglar who brushed against a Hypericum bush during a crime, and has even been proposed as an additive for bullets to enable tracking them. In some Native American religions , pollen was used in prayers and rituals to symbolize life and renewal by sanctifying objects, dancing grounds, trails, and sandpaintings . It may also be sprinkled over heads or in mouths. Many Navajo people believed
365-470: A female lays her fertilized eggs on or just below the surface of the ground. The eggs hatch three to four weeks later. In certain firefly species with aquatic larvae, such as Aquatica leii , the female oviposits on emergent portions of aquatic plants, and the larvae descend into the water after hatching. The larvae feed until the end of the summer. Most fireflies hibernate as larvae. Some do this by burrowing underground, while others find places on or under
438-569: A growing number of anecdotal reports, coupled with several published studies from Europe and Asia, suggest that fireflies are in trouble. Recent IUCN Red List assessments for North American fireflies have identified species with heightened extinction risk in the US, with 18 taxa categorized as threatened with extinction. Fireflies face threats including habitat loss and degradation, light pollution , pesticide use, poor water quality, invasive species, over-collection, and climate change . Firefly tourism,
511-524: A half weeks and emerge as adults. Adult diet varies among firefly species: some are predatory, while others feed on plant pollen or nectar . Some adults, like the European glow-worm, have no mouth, emerging only to mate and lay eggs before dying. In most species, adults live for a few weeks in summer. Fireflies vary widely in their general appearance, with differences in color, shape, size, and features such as antennae. Adults differ in size depending on
584-555: A legend that one night its flaws were repaired by fireflies. In Italy, the firefly ( Italian : lucciola ) appears in Canto XXVI of Dante's Inferno , written in the 14th century: Quante ’l villan ch’al poggio si riposa, nel tempo che colui che ’l mondo schiara la faccia sua a noi tien meno ascosa, come la mosca cede a la zanzara, vede lucciole giù per la vallea, forse colà dov’ e’ vendemmia e ara: di tante fiamme tutta risplendea l’ottava bolgia, ... As many as
657-437: A likely cause of firefly decline. These chemicals can not only harm fireflies directly but also potentially reduce prey populations and degrade habitat. Light pollution is an especially concerning threat to fireflies. Since the majority of firefly species use bioluminescent courtship signals, they are also very sensitive to environmental levels of light and consequently to light pollution . A growing number of studies investigating
730-399: A lumen (plural lumina). These reticulations may also be referred to as brochi. The pollen wall protects the sperm while the pollen grain is moving from the anther to the stigma; it protects the vital genetic material from drying out and solar radiation. The pollen grain surface is covered with waxes and proteins, which are held in place by structures called sculpture elements on the surface of
803-508: A multitude of viruses and eukaryotic parasites are present in the pollen. It is currently unclear if the parasites are introduced by the bee that collected the pollen or if it is from the flower. Though this is not likely to pose a risk to humans, it is a major issue for the bumblebee rearing industry that relies on thousands of tonnes of honey bee collected pollen per year. Several sterilization methods have been employed, though no method has been 100% effective at sterilisation without reducing
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#1732780630061876-538: A pheromone plume. Males can find females without the use of visual cues, so sexual communication in P. hemipterus appears to be mediated entirely by pheromones. The oldest known fossils of the Lampyridae family are Protoluciola and Flammarionella from the Late Cretaceous ( Cenomanian ~ 99 million years ago) Burmese amber of Myanmar, which belong to the subfamily Luciolinae . The light producing organs are clearly present. The ancestral glow colour for
949-505: A pollen allergy is by preventing contact with the material. Individuals carrying the ailment may at first believe that they have a simple summer cold, but hay fever becomes more evident when the apparent cold does not disappear. The confirmation of hay fever can be obtained after examination by a general physician . Antihistamines are effective at treating mild cases of pollinosis; this type of non-prescribed drugs includes loratadine , cetirizine and chlorpheniramine . They do not prevent
1022-562: A population, sexual selection encourages divergence of signaling patterns. Synchronization of flashing occurs in several species; it is explained as phase synchronization and spontaneous order. Tropical fireflies routinely synchronise their flashes among large groups, particularly in Southeast Asia. At night along river banks in the Malaysian jungles, fireflies synchronize their light emissions precisely. Current hypotheses about
1095-425: A process called microsporogenesis , four haploid microspores are produced from each diploid pollen mother cell, after meiotic division . After the formation of the four microspores, which are contained by callose walls, the development of the pollen grain walls begins. The callose wall is broken down by an enzyme called callase and the freed pollen grains grow in size and develop their characteristic shape and form
1168-471: A quickly growing sector of the travel and tourism industry, has also been identified as a potential threat to fireflies and their habitats when not managed appropriately. Like many other organisms, fireflies are directly affected by land-use change (e.g., loss of habitat area and connectivity), which is identified as the main driver of biodiversity changes in terrestrial ecosystems. Pesticides, including insecticides and herbicides , have also been indicated as
1241-424: A resistant outer wall called the exine and an inner wall called the intine. The exine is what is preserved in the fossil record. Two basic types of microsporogenesis are recognised, simultaneous and successive. In simultaneous microsporogenesis meiotic steps I and II are completed before cytokinesis , whereas in successive microsporogenesis cytokinesis follows. While there may be a continuum with intermediate forms,
1314-528: A small number feed on pollen as larvae (including some ant larvae). Spiders are normally considered carnivores but pollen is an important source of food for several species, particularly for spiderlings , which catch pollen on their webs . It is not clear how spiderlings manage to eat pollen however, since their mouths are not large enough to consume pollen grains. Some predatory mites also feed on pollen, with some species being able to subsist solely on pollen, such as Euseius tularensis , which feeds on
1387-797: A widespread anemophilous plant. Arizona was once regarded as a haven for people with pollen allergies, although several ragweed species grow in the desert. However, as suburbs grew and people began establishing irrigated lawns and gardens , more irritating species of ragweed gained a foothold and Arizona lost its claim of freedom from hay fever. Anemophilous spring blooming plants such as oak , birch , hickory , pecan , and early summer grasses may also induce pollen allergies. Most cultivated plants with showy flowers are entomophilous and do not cause pollen allergies. Symptoms of pollen allergy include sneezing , itchy, or runny nose, nasal congestion , red, itchy, and watery eyes. Substances, including pollen, that cause allergies can trigger asthma. A study found
1460-413: Is also associated with asthma exacerbations in some people, a phenomenon termed thunderstorm asthma . In the US, people often mistakenly blame the conspicuous goldenrod flower for allergies. Since this plant is entomophilous (its pollen is dispersed by animals), its heavy, sticky pollen does not become independently airborne. Most late summer and fall pollen allergies are probably caused by ragweed ,
1533-630: Is also present in a wide variety of plants and plant-derived food products. The U.S. Food and Drug Administration (FDA) has not found any harmful effects of bee pollen consumption, except for the usual allergies. However, FDA does not allow bee pollen marketers in the United States to make health claims about their produce, as no scientific basis for these has ever been proven. Furthermore, there are possible dangers not only from allergic reactions but also from contaminants such as pesticides and from fungi and bacteria growth related to poor storage procedures. A manufacturers's claim that pollen collecting helps
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#17327806300611606-468: Is an extensive fossil record of pollen grains, often disassociated from their parent plant. The discipline of palynology is devoted to the study of pollen, which can be used both for biostratigraphy and to gain information about the abundance and variety of plants alive — which can itself yield important information about paleoclimates. Also, pollen analysis has been widely used for reconstructing past changes in vegetation and their associated drivers. Pollen
1679-440: Is an important aspect of the pollination process. Bee pollen for human consumption is marketed as a food ingredient and as a dietary supplement . The largest constituent is carbohydrates , with protein content ranging from 7 to 35 percent depending on the plant species collected by bees. Honey produced by bees from natural sources contains pollen derived p-coumaric acid , an antioxidant and natural bactericide that
1752-409: Is another host to this phenomenon. Female "femme fatale" Photuris fireflies mimic the photic signaling patterns of the smaller Photinus , attracting males to what appears to be a suitable mate, then eating them. This provides the females with a supply of the toxic defensive lucibufagin chemicals. Many fireflies do not produce light. Usually these species are diurnal, or day-flying, such as those in
1825-410: Is around 20–25 μm. Some pollen grains are based on geodesic polyhedra like a soccer ball . Pollen is produced in the microsporangia in the male cone of a conifer or other gymnosperm or in the anthers of an angiosperm flower . In angiosperms, during flower development the anther is composed of a mass of cells that appear undifferentiated, except for a partially differentiated dermis. As
1898-706: Is described as monosulcate , has two sulci, as bisulcate , or more, as polysulcate . Colpate pollen has furrows other than across the middle of the outer faces, and similarly may be described as polycolpate if more than two. Syncolpate pollen grains have two or more colpi that are fused at the ends. Eudicots have pollen with three colpi ( tricolpate ) or with shapes that are evolutionarily derived from tricolpate pollen. The evolutionary trend in plants has been from monosulcate to polycolpate or polyporate pollen. Additionally, gymnosperm pollen grains often have air bladders, or vesicles, called sacci. The sacci are not actually balloons, but are sponge-like, and increase
1971-485: Is first found in the fossil record in the late Devonian period, but at that time it is indistinguishable from spores. It increases in abundance until the present day. Nasal allergy to pollen is called pollinosis , and allergy specifically to grass pollen is called hay fever . Generally, pollens that cause allergies are those of anemophilous plants (pollen is dispersed by air currents.) Such plants produce large quantities of lightweight pollen (because wind dispersal
2044-602: Is frequently portrayed as a sequential process that begins with placement on the vector, moves through travel, and ends with deposition. This transfer can be mediated by the wind, in which case the plant is described as anemophilous (literally wind-loving). Anemophilous plants typically produce great quantities of very lightweight pollen grains, sometimes with air-sacs. Non-flowering seed plants (e.g., pine trees) are characteristically anemophilous. Anemophilous flowering plants generally have inconspicuous flowers. Entomophilous (literally insect-loving) plants produce pollen that
2117-432: Is not the male gamete. It is a gametophyte , something that could be considered an entire organism, which then produces the male gamete. Each pollen grain contains vegetative (non-reproductive) cells (only a single cell in most flowering plants but several in other seed plants) and a generative (reproductive) cell. In flowering plants the vegetative tube cell produces the pollen tube , and the generative cell divides to form
2190-563: Is random and the likelihood of one pollen grain landing on another flower is small), which can be carried for great distances and are easily inhaled, bringing it into contact with the sensitive nasal passages. Pollen allergies are common in polar and temperate climate zones, where production of pollen is seasonal. In the tropics pollen production varies less by the season, and allergic reactions less. In northern Europe, common pollens for allergies are those of birch and alder , and in late summer wormwood and different forms of hay . Grass pollen
2263-403: Is relatively heavy, sticky and protein -rich, for dispersal by insect pollinators attracted to their flowers. Many insects and some mites are specialized to feed on pollen, and are called palynivores . In non-flowering seed plants, pollen germinates in the pollen chamber, located beneath the micropyle , underneath the integuments of the ovule. A pollen tube is produced, which grows into
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2336-409: Is responsible, according to a new study. The researchers attributed roughly half of the lengthening pollen seasons and 8% of the trend in pollen concentrations to climate changes driven by human activity. In Denmark , decades of rising temperatures cause pollen to appear earlier and in greater amounts, exacerbated by the introduction of new species such as ragweed. The most efficient way to handle
2409-586: Is thought to be a severe underestimate as the feeding habits are only known for 1,000 species). Similarly, Ladybird beetles mainly eat insects, but many species also eat pollen, as either part or all of their diet. Hemiptera are mostly herbivores or omnivores but pollen feeding is known (and has only been well studied in the Anthocoridae ). Many adult flies, especially Syrphidae , feed on pollen, and three UK syrphid species feed strictly on pollen (syrphids, like all flies , cannot eat pollen directly due to
2482-428: Is used for transferring haploid male genetic material from the anther of a single flower to the stigma of another in cross-pollination. In a case of self-pollination, this process takes place from the anther of a flower to the stigma of the same flower. Pollen is infrequently used as food and food supplement . Because of agricultural practices, it is often contaminated by agricultural pesticides. Pollen itself
2555-479: Is variously sculptured, and the character of the markings is often of value for identifying genus, species, or even cultivar or individual. The spines may be less than a micron in length (spinulus, plural spinuli) referred to as spinulose (scabrate), or longer than a micron (echina, echinae) referred to as echinate . Various terms also describe the sculpturing such as reticulate , a net like appearance consisting of elements (murus, muri) separated from each other by
2628-421: The buoyancy of the pollen grain and help keep it aloft in the wind, as most gymnosperms are anemophilous . Pollen can be monosaccate , (containing one saccus) or bisaccate (containing two sacci). Modern pine , spruce , and yellowwood trees all produce saccate pollen. The transfer of pollen grains to the female reproductive structure ( pistil in angiosperms) is called pollination . Pollen transfer
2701-408: The nucellus to provide nutrients for the developing sperm cells. Sperm cells of Pinophyta and Gnetophyta are without flagella , and are carried by the pollen tube, while those of Cycadophyta and Ginkgophyta have many flagella. When placed on the stigma of a flowering plant, under favorable circumstances, a pollen grain puts forth a pollen tube , which grows down the tissue of the style to
2774-514: The ovary , and makes its way along the placenta , guided by projections or hairs, to the micropyle of an ovule . The nucleus of the tube cell has meanwhile passed into the tube, as does also the generative nucleus, which divides (if it has not already) to form two sperm cells. The sperm cells are carried to their destination in the tip of the pollen tube. Double-strand breaks in DNA that arise during pollen tube growth appear to be efficiently repaired in
2847-502: The pistil of flowering plants, or from the male cone to the female cone of gymnosperms . If pollen lands on a compatible pistil or female cone, it germinates , producing a pollen tube that transfers the sperm to the ovule containing the female gametophyte. Individual pollen grains are small enough to require magnification to see detail. The study of pollen is called palynology and is highly useful in paleoecology , paleontology , archaeology , and forensics . Pollen in plants
2920-489: The Wikimedia System Administrators, please include the details below. Request from 172.68.168.226 via cp1108 cp1108, Varnish XID 219689901 Upstream caches: cp1108 int Error: 429, Too Many Requests at Thu, 28 Nov 2024 07:57:10 GMT Pollen Pollen grains have a hard coat made of sporopollenin that protects the gametophytes during the process of their movement from the stamens to
2993-472: The bark of trees. They emerge in the spring. At least one species, Ellychnia corrusca , overwinters as an adult. The larvae of most species are specialized predators and feed on other larvae, terrestrial snails , and slugs . Some are so specialized that they have grooved mandibles that deliver digestive fluids directly to their prey. The larval stage lasts from several weeks up to, in certain species, two or more years. The larvae pupate for one to two and
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3066-468: The bee colonies is also controversial. Pine pollen ( 송화가루 ; Songhwa Garu ) is traditionally consumed in Korea as an ingredient in sweets and beverages. The growing industries in pollen harvesting for human and bee consumption rely on harvesting pollen baskets from honey bees as they return to their hives using a pollen trap . When this pollen has been tested for parasites, it has been found that
3139-474: The body became holy when it traveled over a trail sprinkled with pollen. For agricultural research purposes, assessing the viability of pollen grains can be necessary and illuminating. A very common, efficient method to do so is known as Alexander's stain. This differential stain consists of ethanol , malachite green , distilled water , glycerol , phenol , chloral hydrate , acid fuchsin , orange G , and glacial acetic acid . (A less-toxic variation omits
3212-604: The causes of this behavior involve diet, social interaction, and altitude. In the Philippines, thousands of fireflies can be seen all year-round in the town of Donsol . In the United States, one of the most famous sightings of fireflies blinking in unison occurs annually near Elkmont, Tennessee , in the Great Smoky Mountains during the first weeks of June. Congaree National Park in South Carolina
3285-645: The dimly glowing " blue ghost " of the Eastern US may seem to emit blueish-white light from a distance and in low light conditions, but their glow is bright green when observed up close. Their perceived blue tint may be due to the Purkinje effect . During a study on the genome of Aquatica leii , scientists discovered two key genes are responsible for the formation, activation, and positioning of this firefly's light organ: Alabd-B and AlUnc-4. Adults emit light primarily for mate selection. Early larval bioluminescence
3358-557: The discharge of histamine , but it has been proven that they do prevent a part of the chain reaction activated by this biogenic amine , which considerably lowers hay fever symptoms. Decongestants can be administered in different ways such as tablets and nasal sprays . Allergy immunotherapy (AIT) treatment involves administering doses of allergens to accustom the body to pollen, thereby inducing specific long-term tolerance. Allergy immunotherapy can be administered orally (as sublingual tablets or sublingual drops), or by injections under
3431-566: The effects of artificial light at night on fireflies has shown that light pollution can disrupt fireflies' courtship signals and even interfere with larval dispersal. Researchers agree that protecting and enhancing firefly habitat is necessary to conserve their populations. Recommendations include reducing or limiting artificial light at night, restoring habitats where threatened species occur, and eliminating unnecessary pesticide use, among many others. Sundarbans Firefly Sanctuary in Bangladesh
3504-816: The evolution of flash signaling in the lineage, and is retained today in diurnally-active species. Some species, especially lightning bugs of the genera Photinus , Photuris , and Pyractomena , are distinguished by the unique courtship flash patterns emitted by flying males in search of females. In general, females of the genus Photinus do not fly, but do give a flash response to males of their own species. Signals, whether photic or chemical, allow fireflies to identify mates of their own species. Flash signaling characteristics include differences in duration, timing, color, number and rate of repetitions, height of flight, and direction of flight (e.g. climbing or diving) and vary interspecifically and geographically. When flash signals are not sufficiently distinguished between species in
3577-444: The fireflies which the peasant sees in the [ Tuscan ] valley below, when he is resting on the hill—in the season [midsummer] when the sun hides least from us, and at the time of day [dusk] when the fly gives place to the mosquito—perhaps in the fields where he tills the ground and gathers in the grapes; with that many flames the eighth ditch [of Hell] was shining, ... Cheguevariinae Too Many Requests If you report this error to
3650-462: The flower develops, fertile sporogenous cells, the archespore , form within the anther. The sporogenous cells are surrounded by layers of sterile cells that grow into the wall of the pollen sac. Some of the cells grow into nutritive cells that supply nutrition for the microspores that form by meiotic division from the sporogenous cells. The archespore cells divide by mitosis and differentiate to form pollen mother cells (microsporocyte, meiocyte ). In
3723-441: The generative cell forming the two sperm cells. Except in the case of some submerged aquatic plants, the mature pollen grain has a double wall. The vegetative and generative cells are surrounded by a thin delicate wall of unaltered cellulose called the endospore or intine , and a tough resistant outer cuticularized wall composed largely of sporopollenin called the exospore or exine . The exine often bears spines or warts, or
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#17327806300613796-427: The generative cell that carries the male genomic information to be passed on to the next plant generation. However, the vegetative cell that is responsible for tube elongation appears to lack this DNA repair capability. The sporopollenin outer sheath of pollen grains affords them some resistance to the rigours of the fossilisation process that destroy weaker objects; it is also produced in huge quantities. There
3869-679: The genus Ellychnia . A few diurnal fireflies that inhabit primarily shadowy places, such as beneath tall plants or trees, are luminescent. One such genus is Lucidota . Non-bioluminescent fireflies use pheromones to signal mates. Some basal groups do not show bioluminescence and use chemical signaling, instead. Phosphaenus hemipterus has photic organs, yet is a diurnal firefly and displays large antennae and small eyes. These traits strongly suggest pheromones are used for sexual selection, while photic organs are used for warning signals. In controlled experiments, males coming from downwind arrived at females first, indicating that males travel upwind along
3942-475: The grain. The outer pollen wall, which prevents the pollen grain from shrinking and crushing the genetic material during desiccation, is composed of two layers. These two layers are the tectum and the foot layer, which is just above the intine. The tectum and foot layer are separated by a region called the columella, which is composed of strengthening rods. The outer wall is constructed with a resistant biopolymer called sporopollenin. Pollen apertures are regions of
4015-544: The identification of classes of pollen. Pollen may be referred to as inaperturate (apertures absent) or aperturate (apertures present). The aperture may have a lid ( operculum ), hence is described as operculate . However the term inaperturate covers a wide range of morphological types, such as functionally inaperturate (cryptoaperturate) and omniaperturate. Inaperaturate pollen grains often have thin walls, which facilitates pollen tube germination at any position. Terms such as uniaperturate and triaperturate refer to
4088-499: The last common ancestor of all living fireflies has been inferred to be green, based on genomic analysis . The fireflies (including the lightning bugs) are a family, Lampyridae, of some 2,000 species within the Coleoptera. The family forms a single clade , a natural phylogenetic group. The term glowworm is used for both adults and larvae of firefly species such as Lampyris noctiluca , the common European glowworm, in which only
4161-578: The location of the light organ varies among species and between sexes of the same species. Fireflies have attracted human attention since classical antiquity ; their presence has been taken to signify a wide variety of conditions in different cultures and is especially appreciated aesthetically in Japan, where parks are set aside for this specific purpose. Fireflies are beetles and in many aspects resemble other beetles at all stages of their life cycle , undergoing complete metamorphosis . A few days after mating,
4234-1009: The nonflying adult females glow brightly; the flying males glow weakly and intermittently. In the Americas , "glow worms" are the closely related Coleopteran family Phengodidae , while in New Zealand and Australia, a "glow worm" is a luminescent larva of the fungus gnat Arachnocampa , within the true flies, Diptera . The phylogeny of the Lampyridae family, based on both phylogenetic and morphological evidence by Martin et al. 2019, is: [REDACTED] Elateridae [REDACTED] Rhagophthalmidae Phengodidae [REDACTED] Luciolinae [REDACTED] Pterotinae [REDACTED] Ototretinae [REDACTED] Lamprohizinae [REDACTED] Psilocladinae Amydetinae Photurinae [REDACTED] Lampyrinae [REDACTED] Firefly populations are thought to be declining worldwide. While monitoring data for many regions are scarce,
4307-416: The number of apertures present (one and three respectively). Spiraperturate refers to one or more apertures being spirally shaped. The orientation of furrows (relative to the original tetrad of microspores) classifies the pollen as sulcate or colpate . Sulcate pollen has a furrow across the middle of what was the outer face when the pollen grain was in its tetrad. If the pollen has only a single sulcus, it
4380-495: The nutritional value of the pollen In forensic biology , pollen can tell a lot about where a person or object has been, because regions of the world, or even more particular locations such a certain set of bushes, will have a distinctive collection of pollen species. Pollen evidence can also reveal the season in which a particular object picked up the pollen. Pollen has been used to trace activity at mass graves in Bosnia , catch
4453-474: The pollen of dozens of plant species. Members of some beetle families such as Mordellidae and Melyridae feed almost exclusively on pollen as adults, while various lineages within larger families such as Curculionidae , Chrysomelidae , Cerambycidae , and Scarabaeidae are pollen specialists even though most members of their families are not (e.g., only 36 of 40,000 species of ground beetles , which are typically predatory, have been shown to eat pollen—but this
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#17327806300614526-455: The pollen wall that may involve exine thinning or a significant reduction in exine thickness. They allow shrinking and swelling of the grain caused by changes in moisture content. The process of shrinking the grain is called harmomegathy. Elongated apertures or furrows in the pollen grain are called colpi (singular: colpus) or sulci (singular: sulcus ). Apertures that are more circular are called pores. Colpi, sulci and pores are major features in
4599-556: The presence of magnesium ions, ATP , and oxygen to produce light. Oxygen is supplied via an abdominal trachea or breathing tube. Gene coding for these substances has been inserted into many different organisms . Firefly luciferase is used in forensics , and the enzyme has medical uses – in particular, for detecting the presence of ATP or magnesium. Fireflies produce a "cold light", with no infrared or ultraviolet frequencies. The light may be yellow, green, or pale red, with wavelengths from 510 to 670 nanometers. Some species such as
4672-429: The skin (subcutaneous). Discovered by Leonard Noon and John Freeman in 1911, allergy immunotherapy represents the only causative treatment for respiratory allergies. Most major classes of predatory and parasitic arthropods contain species that eat pollen, despite the common perception that bees are the primary pollen-consuming arthropod group. Many Hymenoptera other than bees consume pollen as adults, though only
4745-614: The species, with the largest up to 25 mm (1 in) long. Many species have non-flying larviform females . These can often be distinguished from the larvae only because the adult females have compound eyes , unlike the simple eyes of larvae, though the females have much smaller (and often highly regressed) eyes than those of their males. The most commonly known fireflies are nocturnal , although numerous species are diurnal and usually not luminescent; however, some species that remain in shadowy areas may produce light. Most fireflies are distasteful to vertebrate predators, as they contain
4818-453: The steroid pyrones lucibufagins , similar to the cardiotonic bufadienolides found in some poisonous toads. All fireflies glow as larvae, where bioluminescence is an honest aposematic warning signal to predators . Light production in fireflies is due to the chemical process of bioluminescence . This occurs in specialized light-emitting organs , usually on a female firefly's lower abdomen . The enzyme luciferase acts on luciferin , in
4891-408: The structure of their mouthparts, but can consume pollen contents that are dissolved in a fluid). Some species of fungus, including Fomes fomentarius , are able to break down grains of pollen as a secondary nutrition source that is particularly high in nitrogen. Pollen may be valuable diet supplement for detritivores , providing them with nutrients needed for growth, development and maturation. It
4964-420: The two sperm nuclei. Pollen grains come in a wide variety of shapes, sizes, and surface markings characteristic of the species (see electron micrograph , right). Pollen grains of pines , firs , and spruces are winged. The smallest pollen grain, that of the forget-me-not ( Myosotis spp.), is 2.5–5 μm (0.005 mm) in diameter. Corn pollen grains are large, about 90–100 μm. Most grass pollen
5037-415: The type of microsporogenesis has systematic significance. The predominant form amongst the monocots is successive, but there are important exceptions. During microgametogenesis, the unicellular microspores undergo mitosis and develop into mature microgametophytes containing the gametes. In some flowering plants, germination of the pollen grain may begin even before it leaves the microsporangium, with
5110-435: Was adopted in the phylogeny of adult fireflies, and was repeatedly gained and lost before becoming fixed and retained as a mechanism of sexual communication in many species. Adult lampyrids have a variety of ways to communicate with mates in courtships: steady glows, flashing, and the use of chemical signals unrelated to photic systems. Chemical signals, or pheromones, are the ancestral form of sexual communication; this pre-dates
5183-414: Was established in 2019. Fireflies have featured in human culture around the world for centuries. In Japan, the emergence of fireflies ( Japanese : hotaru ) signifies the anticipated changing of the seasons; firefly viewing is a special aesthetic pleasure of midsummer, celebrated in parks that exist for that one purpose. The Japanese sword called Hotarumaru , made in the 14th century, is so named for
5256-508: Was suggested that obtaining nutrients from pollen, deposited on the forest floor during periods of pollen rains, allows fungi to decompose nutritionally scarce litter. Some species of Heliconius butterflies consume pollen as adults, which appears to be a valuable nutrient source, and these species are more distasteful to predators than the non-pollen consuming species. Although bats , butterflies and hummingbirds are not pollen eaters per se , their consumption of nectar in flowers
5329-519: Was then co-opted as a mating signal and, in a further development, adult female fireflies of the genus Photuris mimic the flash pattern of the Photinus beetle in order to trap their males as prey. Fireflies are found in temperate and tropical climates. Many live in marshes or in wet, wooded areas where their larvae have abundant sources of food. While all known fireflies glow as larvae, only some species produce light in their adult stage, and
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