Mason bees mate immediately after hatching in the spring. The female then searches for an appropriate hole or crevice to build her nest. After preparing a brood chamber, she gathers pollen and nectar until she has enough to feed a larva to adulthood.
In entomology, the term brood is used to refer to the embryo or egg, the larva and the pupa stages in the life of holometabolous insects. The brood of honey bees develops within a bee hive. In man-made, removable frame hives, such as Langstroth hives, each frame which is mainly brood is called a brood frame. Brood frames usually have some pollen and nectar or honey in the upper corners of the frame. The rest of the brood frames cells may be empty or occupied by brood in various developmental stages. During the brood raising season, the bees may reuse the cells from which brood has emerged for additional brood or convert it to honey or pollen storage. Bees show remarkable flexibility in adapting cells to a use best suited for the hive's survival.
In modern removable frame hives the nursery area is in the brood chamber, which beekeepers prefer to be in the bottom box. In the late winter and early spring as the brood cycle begins, the queen starts to lay eggs within the winter cluster in proximity to available honey stores. Honey bees tend to greatly expand the brood chamber as the season progresses. The relative location of the brood chamber within the beehive may also change as bee keepers add more boxes or as wild bees build fresh comb into available cavities. Some beekeepers ensure that the queen will not go into the upper boxes (called supers or honey supers) by placing a screen called a queen excluder between the boxes. The screen has precisely measured open spaces through which a worker bee can pass, but not a queen. Some beekeepers do not use excluders, but try to keep the queen within the intended brood area by keeping a honey barrier of capped honey, which the queen is reluctant to cross, above the brood. In feral hives the honey bees tend to put the brood at bottom center of the cavity, and honey to the sides and above the brood, so beekeepers are trying to follow the natural tendency of the bees.
In the mid to late spring, just before a bee hive would naturally split by swarming, beekeepers often remove frames of brood, with adhering bees, to make up new starter hives, called "nucs" or nucleus colonies. In areas where the climate is mild, one frame may be sufficient to start a new colony, with an added queen. But usually two to three frames are used, together with a frame that is predominantly honey. This ensures that there will be enough adult bees to provide the brood the adequate temperature and sufficient feed if there are a few rainy days when bees cannot gather nectar. If there are not enough adult bees to warm the combs, the brood may die from cold temperature overnight (aptly called "chilled brood").
Bee brood frames are composed of brood at various stages of development - eggs, larvae, and pupae. In each cell of honeycomb, the queen lays an egg, gluing it to the bottom of the cell. The queen tends to lay brood in a circular or oval pattern. At the height of the brood laying season, the queen may lay so many eggs per day, that the brood on a particular frame may be virtually of the same age.
As the egg hatches, worker bees add royal jelly - a secretion from glands on the heads of young bees. For three days the young larvae are fed royal jelly, then they are fed nectar or diluted honey and pollen. A few female larvae in special queen cups may be selected to become queens. Their special queen cups are flooded with royal jelly for six days. The extra royal jelly speeds up the queen larvae development. Only the queen will have fully developed ovaries, i.e. she will be sexually mature. Drone brood develops from unfertilized eggs. Drone brood cells are larger than the cells of female worker bees.
Young larvae eat their way through the royal jelly in a circular pattern until they become crowded, then they stretch out lengthwise in the cell. Soon they begin to spin a cocoon, and their older sisters cap the cell as they go into the pupa stage. These cells collectively are called "capped brood."
Hives that are rated for pollination purposes are generally evaluated in terms of the number of frames of brood.
Nectar is a sugar-rich liquid produced by plants. It is produced in glands called nectaries, either within the flowers in which it attracts pollinating animals, or by extrafloral nectaries which provide a nutrient source to animal mutualists, which in turn provide anti-herbivore protection. Common nectar-consuming pollinators include bees, butterflies and moths, hummingbirds and bats.
Nectar is an ecologically important item, the sugar source for honey. It is also useful in agriculture and horticulture because the adult stages of some predatory insects feed on nectar such as almost all solitary wasps. In turn, these wasps then hunt agricultural pest insects as food for their young. For example, thread-waisted wasps (genus Ammophila) are known for hunting caterpillars that are destructive to crops.][
Nectar secretion increases as the flower is visited by pollinators. After pollination, the nectar is frequently reabsorbed into the plant.
Nectar is derived from Latin nectar, the favored drink of the gods, which in turn is the Latinized version of Greek νέκταρ, néktar, presumed to be a compound of the PIE roots *nek-, "death", and -*tar, "overcoming", i.e. has a similar etymology to ambrosia. The earliest recorded use of its current meaning, "sweet liquid in flowers," was in AD 1609.
Floral nectaries are generally located at the base of the perianth, so that pollinators are made to brush the flower's reproductive structures, the anthers and pistil, while accessing the nectar.
Extrafloral nectaries (also known as extranuptial nectaries) are nectar-secreting plant glands that develop outside of flowers and are not involved in pollination. They are highly diverse in form, location, size, and mechanism. They have been described in virtually all above-ground plant parts—including leaves (in which case they are known as foliar nectaries), petioles, stipules, cotyledons, fruits, and stems, among others. They range from single-celled trichomes to complex cup-like structures that may or may not be vascularized.
In contrast to floral nectaries, nectar produced outside the flower generally have a defensive function. The nectar attract predatory insects who will eat both the nectar and any plant-eating insects around, thus functioning as 'bodyguards'. Foraging predatory insects show a preference for plants with extrafloral nectaries, particularly some species of ants and wasps which have been observed to directly defend the plants. Among passion flowers, for example, extrafloral nectaries prevent herbivores by attracting ants and deterring two species of butterflies from laying eggs. In many carnivorous plants, extrafloral nectaries are also used to attract insect prey.
Extrafloral nectaries were originally believed to simply be excretory in nature (hydathodes). Their defensive functions were first recognized by the Italian botanist Federico Delpino in his important monograph Funzione mirmecofila nel regno vegetale (1886). Delpino's study was inspired by a disagreement between him and Charles Darwin with whom he corresponded with regularly. Darwin believed that extrafloral nectaries were simply hydathodes, while Delpino believed they had a defensive function, especially among myrmecophilic plants.
Extrafloral nectaries have been reported in over 3941 species of vascular plants belonging to 745 genera and 108 families. 99.7% of which belong to flowering plants (angiosperms), comprising 1.0 to 1.8% of all known species. They are most common among eudicots, occurring in 3642 species (of 654 genera and 89 families), particularly among rosids which comprise more than half of the known occurrences. The families showing the most number of recorded occurrences of extrafloral nectaries are Fabaceae, with 1069 species; Passifloraceae, with 438 species; and Malvaceae, with 301 species. The genera with the most number of recorded occurrences of extrafloral nectaries are Passiflora (322 species, Passifloraceae), Inga (294 species, Fabaceae), and Acacia (204 species, Fabaceae). Other genera with extrafloral nectaries include Salix (Salicaceae), Prunus (Rosaceae) and Gossypium (Malvaceae).
Foliar nectaries have also been observed in 39 species of ferns belonging to 7 genera and 4 families of Cyatheales and Polypodiales. They are absent, however, in bryophytes, gymnosperms, early angiosperms, magnoliids, and members of Apiales among the eudicots. Phylogenetic studies and the wide distribution of extrafloral nectaries among vascular plants point to multiple independent evolutionary origins of extrafloral nectaries in at least 457 independent lineages.
Although its main ingredient is natural sugar (i.e., sucrose (table sugar), glucose, and fructose), nectar is a brew of many chemicals. For example, the Nicotiana attenuata, a tobacco plant native to the US state of Utah, uses several volatile aromas to attract pollinating birds and moths. The strongest such aroma is benzyl acetone, but the plant also adds bitter nicotine, which is less aromatic and therefore may not be detected by the bird until after taking a drink. Researchers speculate the purpose of this addition is to drive the bird away after only a sip, motivating it to visit other plants to fill its hunger, and therefore maximizing the pollination efficiency gained by the plant for a minimum nectar output. Neurotoxins such as aesculin are present in some nectars such as that of the California Buckeye. All twenty of the normal amino acids found in protein have been identified in various nectars, with alanine, arginine, serine, proline, glycine, isoleucine, threonine, and valine being the most prevalent.
Stingless bees, sometimes called stingless honey bees or simply meliponines, are a large group of bees (approximately 500 species), comprising the tribe Meliponini (or subtribe Meliponina according to other authors). They belong in the family Apidae, and are closely related to common honey bees, carpenter bees, orchid bees and bumblebees. The common name is slightly misleading as male bees and bees of other species, such as those in the family Andrenidae, cannot sting. Meliponines have stingers, but they are highly reduced and cannot be used for defense.
Stingless bees can be found in most tropical or subtropical regions of the world, such as Australia, Africa, Southeast Asia, and tropical America. The majority of native eusocial bees of Central and South America are stingless bees, although only a few of them produce honey on a scale such that they are farmed by humans. They are also quite diverse in Africa, including Madagascar, and are farmed there also; meliponine honey is prized as a medicine in many African communities as well as in South America.
Being tropical, stingless bees are active all year round, although they are less active in cooler weather, with some species presenting diapause. Unlike other eusocial bees, they do not sting but will defend by biting if their nest is disturbed. In addition, a few (in the genus Oxytrigona) have mandibular secretions that cause painful blisters. Despite their lack of a sting, stingless bees, being eusocial, may have very large colonies made formidable by the number of defenders.
Stingless bees usually nest in hollow trunks, tree branches, underground cavities, or rock crevices but they have also been encountered in wall cavities, old rubbish bins, water meters, and storage drums. Many beekeepers keep the bees in their original log hive or transfer them to a wooden box, as this makes it easier to control the hive.
The bees store pollen and honey in large egg-shaped pots made of beeswax, typically mixed with various types of plant resin (sometimes called "propolis"). These pots are often arranged around a central set of horizontal brood combs, where the larval bees are housed. When the young worker bees emerge from their cells, they tend to remain inside the hive, performing different jobs. As workers age, they become guards or foragers. Unlike the larvae of honey bees, meliponine larvae are not fed directly. The pollen and nectar are placed in a cell, an egg is laid, and the cell is sealed until the adult bee emerges after pupation ("mass provisioning"). At any one time, hives can contain 300–80,000 workers, depending on species.
In a simplified sense, the sex of each bee depends on the number of chromosomes it receives. Female bees have two sets of chromosomes (diploid)—one set from the queen and another from one of the male bees or drones. Drones have only one set of chromosomes (haploid), and are the result of unfertilized eggs, though inbreeding can result in diploid drones.
Unlike true honey bees, whose female bees may become workers or queens strictly depending on what kind of food they receive as larvae (queens are fed royal jelly and workers are fed pollen), the caste system in meliponines is variable, and commonly based simply on the amount of pollen consumed; larger amounts of pollen yield queens in the genus Melipona. There is also a genetic component however, and as much as 25% (typically 5–14%) of the female brood may be queens. Queen cells in the former case can be distinguished from others by their larger size, as they are stocked with more pollen, but in the latter case the cells are identical to worker cells, and scattered among the worker brood. When the new queens emerge, they typically leave to mate, and most die. New nests are not established via swarms, but by a procession of workers who gradually construct a new nest at a secondary location. The nest is then joined by a newly mated queen, at which point many workers take up permanent residence and help the new queen raise her own workers. If a ruling queen is herself weak or dying, then a new queen can replace her.][ For Plebeia quadripunctata, although less than 1% of female worker cells produce dwarf queens, they comprise six out of seven queen bees, and one out of five proceed to head colonies of their own. They are reproductively active but less fecund than large queens.
Of the 1,600 species of wild bees native to Australia, about 14 species are stingless. These species bear a variety of names, including Australian native honey bees, native bees, sugar-bag bees and sweat bees (because they will land on a sweaty person to drink in dry times/areas). All are small, black in colour, with hairy extended hind legs for carrying nectar and pollen; because of the latter they are sometimes mistaken for bumblebees. The various stingless species look quite similar, with the two most common species, Trigona carbonaria and Austroplebeia australis, displaying the greatest variation, as the latter is smaller and less active. Both of these inhabit the area around Brisbane.
As stingless bees are harmless to humans, they have become an increasingly attractive addition to the suburban backyard. Most meliponine beekeepers do not keep the bees for honey but rather for the pleasure of conserving a native species whose original habitat is declining due to human development. In return, the bees pollinate crops, garden flowers, and bushland during their search for nectar and pollen.
While a number of beekeepers fill a small niche market for bush honey, native meliponines only produce small amounts and the structure of their hives makes the honey difficult to extract. It is only in warm areas of Australia such as Queensland and northern New South Wales that the bees can produce more honey than they need for their own survival. Harvesting honey from a nest in a cooler area could weaken or even kill the nest.
In warm areas of Australia, these bees can be used for minor honey production. They may also be kept successfully in boxes in these areas. Special methods are being developed to harvest moderate amounts of honey from stingless bees in these areas without causing harm.
Like the European honey bee (Apis mellifera), which provides most of Australia's commercially produced honey, stingless bees have enlarged areas on their back legs for carrying pollen back to the hive. After a foraging expedition, these pollen baskets or corbiculae can be seen stuffed full of bright orange or yellow pollen. Stingless bees also collect nectar, which they store in an extension of their gut called a crop. Back at the hive, the bees ripen or dehydrate the nectar droplets by spinning them inside their mouthparts until honey is formed. Ripening concentrates the nectar and increases the sugar content, though it is not nearly as concentrated as the honey from true honey bees; it is much thinner in consistency, and more prone to spoiling.
Stingless bees store their aromatic honey in clusters of small resin pots near the extremities of the nest. For honey production, the bees need to be kept in a box specially designed to make the honey stores accessible without damaging the rest of the nest structure. Some recent box designs for honey production provide a separate compartment for the honey stores so that honey pots can be removed without spilling honey into other areas of the nest.
Unlike a hive of commercial honeybees, which can produce 75 kilograms of honey a year, a hive of Australian stingless bees produces less than one kilogram. Stingless bee honey has a distinctive "bush" taste—a mix of sweet and sour with a hint of fruit. The taste comes from plant resins—which the bees use to build their hives and honey pots—and varies at different times of year depending on the flowers and trees visited.
Australian farmers rely heavily on the introduced Western honey bee to pollinate their crops. However, for some crops native bees may be better pollinators. Stingless bees have been shown to be valuable pollinators of crops such as macadamias and mangoes. They may also benefit strawberries, watermelons, citrus, avocados, lychees and many others. Research into the use of stingless bees for crop pollination in Australia is still in its very early stages, but these bees show great potential. Studies at the University of Western Sydney have shown these bees' excellent ability to work in confined areas such as glasshouses.
Brazil is home to several species of stingless bees belonging to meliponini tribe, with more than 300 species already identified and probably more yet to be discovered. 20 to 30 of these species have good potential as honey producers, and there are an increasing number of beekeepers dedicated to these bees. This activity has experienced significant growth throughout the country since August 2004, when national laws were changed to allow colonies of native species to be freely marketed, which was previously forbidden in an unsuccessful attempt to protect the species. Nowadays the capture or destruction of existing colonies in nature is still forbidden, and only new colonies formed by the bees themselves in artificial traps can be collected from the wild. Most colonies marketed are artificially produced by authorized beekeepers, through division of already existing captive colonies.
Also, much practical and academic work is being done about the best ways of keeping such bees, multiply their colonies and exploring the honey they produce. Among many others, species like jandaíra (Melipona subnitida) and true-uruçu (Melipona scutellaris) in the northeast of the country, mandaçaia (Melipona quadrifasciata) and yellow uruçu (Melipona rufiventris) in the south-southeast, jupara (Melipona compressipes manaosensis) and straw-bee (Scaptotrigona polistycta) in the north and jataí (Tetragonisca angustula) throughout the country are increasingly kept by small, medium and large producers. Through cultivation of honey or selling the colonies themselves, keeping stingless bees is an increasingly profitable activity. A single colony of species like mandaçaia and true-uruçu can be divided up to 4 times a year, and each of the new colonies obtained this way can be sold by about US$100.
Although the colony sizes of most of these bees are much smaller than those of the European honey bee, the per bee productivity can be quite high, with colonies containing less than a thousand bees been able to produce up to 3 or 4 liters of honey every year. Species of the genus Scaptotrigona have very large colonies and can produce from 8 to 12 liters of honey a year, but are somewhat aggressive and thus not popular among Brazilian meliponine beekeepers. Some larger breeders have more than 3,000 hives of the more tame but still highly productive species in the genus melipona, like the true uruçu and the jandaíra, each with 3,000 or more bees, and can produce over 1.5 tons of honey per year (in large bee farms the availability of flowers limits the honey production per colony). Being considered more palatable by not being overly sweet, and also having medicinal properties more pronounced than honey from bees of the apis genus due to the presence of anti-microbial substances at a much higher level, the honey from stingless bees returns very high values in the market, even five or ten times greater than the common honey produced by European or Africanized bees. This makes production very interesting, even though a much larger number of beehives is required so that they can produce equivalent amounts of honey.
The honey from stingless bees has a lighter color and a higher water content (from 25% up to 35%) compared to the honey from the genus apis, whose honey consists of 20% or less of water. This contributes to its less cloying taste, but also causes it to spoil more easily. Thus, for marketing, this honey needs to be processed through desiccation or pasteurization. In its natural state, it should be kept under refrigeration.
Due to the lack of a functional stinger and characteristic non-aggressive behavior of many Brazilian species of stingless bees, they can be kept without problems in densely populated environments such as cities, provided there are enough flowers at their disposal nearby. Some breeders (called meliponicultors) can produce honey even in apartments, up to the 12th floor.
Despite being in general fairly peaceful, with exception of a few species like the tubuna (Scaptotrigona bipuntacta), most Brazilian meliponini bees will usually react if their hives are molested, nipping with their jaws, entangling themselves in the hair and releasing propolis or even acid over their aggressors. But some species as the mandaçaia are extremely tame, not attacking humans even when their hives are opened for honey extraction or colony division. This, plus the fact it only form small colonies with 500 or 600 individuals, makes them particularly suitable for keeping at home as pets. And one single rational beehive of mandaçaia can produce up to 4 liters of honey a year, making the species very attractive for home keepers. However, it is somewhat selective about which flowers to visit, preferring the flora that occurs in their natural environment, and thus is difficult to be kept outside its region of origin, which is along the east coast of Brazil, from the state of Bahia to the south. Other species like the Tiúba (Melipona compressipes) and the True-uruçu (Melipona scutellaris) are also very tame and productive, but can only survive in regions with warm climate.
Another species suitable for keeping at home is the guaraipo (Melipona bicolor). It is also quite tame, their colonies don´t grow too big and they can produce two to three liters of honey a year. One interesting thing about this species is that their colonies usually have more than one single queen at a time (usually two or three, but there can be up to five), a phenomenon called poliginy. But once very common, the guaraipo is now rather rare in nature, mainly due to the destruction of the forests where they could be found, in the south-southeast of Brazil.
Other groups of Brazilian stingless bees, belonging to the tribe trigonini, genera plebeia, frieseomelitta and leurotrigona are also very tame and much smaller, one of them (Plebeia minima) reaching no more than 2.5 mm in length, and the lambe-olhos (licks-eyes, Leurotrigona muelleri) been even smaller, with 1.5 mm in length. Many of these species are generally known as "mirim" (kid), and they can be kept in very small artificial hives thus been interesting for keepers who wants them just for the pleasure of having a "toy" bee colony at home. Been so tiny these species produce only a very small amount of honey, typically less than 500 ml a year, and are thus unsuitable for commercial honey production.
The stingless bees Melipona beecheii and M. yucatanica are the only native bees cultured to any degree in Central America. They were extensively cultured by the Maya for honey, and regarded as sacred. These bees are endangered due to massive deforestation, altered agricultural practices (especially insecticides), and changing beekeeping practices with the arrival of the Africanized honey bee, which produces much greater honey crops.
Native meliponines (Melipona beecheii being the favorite) have been kept by the lowland Maya for thousands of years. The traditional Mayan name for this bee is Xunan kab, literally meaning "royal lady". The bees were once the subject of religious ceremonies and were a symbol of the bee-god Ah-Muzen-Cab, who is known from the Madrid Codex.
The bees were, and still are, treated as pets. Families would have one or many log-hives hanging in and around their house. Although they are stingless, the bees do bite and can leave welts similar to a mosquito bite. The traditional way to gather bees, still favored among the locals, is find a wild hive; then the branch is cut around the hive to create a portable log, enclosing the colony. This log is then capped on both ends with another piece of wood or pottery and sealed with mud. This clever method keeps the melipine bees from mixing their brood, pollen, and honey in the same comb as the European bees. The brood is kept in the middle of the hive, and the honey is stored in vertical "pots" on the outer edges of the hive. A temporary, replaceable cap at the end of the log allows for easy access to the honey while doing minimal damage to the hive. However, inexperienced handlers can still do irreversible damage to a hive, causing the hive to swarm and abscond from the log. On the other hand, with proper maintenance, hives have been recorded as lasting over 80 years, being passed down through generations. In the archaeological record of Mesoamerica, stone discs have been found that are generally considered to be the caps of long-disintegrated logs that once housed the beehives.
Tulum, the site of an ancient Mayan city on the Caribbean coast 130 km south of Cancun, has a god depicted repeatedly all over the site. Upside down, he appears as a small figure over many doorways and entrances. One of the temples, the "Templo del Dios Descendente" or the Temple of the Descending God, stands just left of the central plaza. Speculation is that he may be the "Bee God", Ah Muzen Cab, as seen in the Madrid Codex. It is possible that this was a religious/trade center with emphasis on Xunan kab, the "royal lady".
Balché, a traditional Mesoamerican alcoholic beverage similar to mead, was made from fermented honey and the bark of the leguminous Balché tree (Lonchocarpus violaceus), hence its name. It was traditionally brewed in a canoe. The drink was known to have entheogenic properties, that is, to produce mystical experiences, and was consumed in medicinal and ritual practices. Beekeepers would place the nests near the psychoactive plant Turbina corymbosa and possibly near Balché trees, forcing the bees to use nectar from these plants to make their honey. Additionally, brewers would add extracts of the bark of the Balché tree to the honey mixture before fermentation. The resulting beverage is responsible for psychotropic effects when consumed, due to the ergoline compounds in the pollen of the T. corymbosathe, the Melipona nectar gathered from the Balché flowers, or the hallucinogenic compounds of the Balché tree bark.
Lost-wax casting, a common metalworking method typically found where the inhabitants keep bees, was also used by the Maya. The wax from Melipona is soft and easy to work, especially in the humid Mayan lowland. This allowed the Maya to create smaller works of art, jewelry, and other metalsmithing that would be difficult to forge. It also makes use of the leftovers from honey extraction. If the hive was damaged beyond repair, the whole of the comb could be used, thus using all of the hive. With experienced keepers, though, only the honey pot could be removed, the honey extracted, and the wax used for casting or other purposes.
The outlook for meliponines in Mesoamerica is grim. The number of active Melipona beekeepers is rapidly declining in favor of the more economical, non-indigenous Africanized Apis mellifera. The high honey yield, 100 kilograms or more annually, along with the ease of hive care and ability to create new hives from existing stock, commonly outweighs the negative consequences of "killer bee" hive maintenance. Furthermore, there are flora that the Africanized honey bees do not visit, such as those in the tomato family, and several forest trees and shrubs, which rely on the native stingless bees for pollination. There has already been a decline in populations of native flora in areas where stingless bees have been displaced by Africanized honey bees. An additional blow to the art of meliponine beekeeping is that many of the meliponine beekeepers are now elderly men and women, whose hives may not be cared for once they die. The hives are considered similar to an old family collection, to be parted out once the collector dies or to be buried in whole or part along with the beekeeper upon death. In fact, a survey of a once-popular area of the Mayan lowlands shows the rapid decline of beekeepers, down to around 70 in 2004 from thousands in the late 1980s. It is traditional in the Mayan lowlands that the hive itself or parts of the hive be buried along with the beekeeper to volar al cielo, "to fly to heaven".][ There are conservation efforts underway in several parts of Mesoamerica.
Carpenter bees (the genus Xylocopa in the subfamily Xylocopinae) are large bees distributed worldwide. There are some 500 species of carpenter bee in 31 subgenera. Their name comes from the fact that nearly all species build their nests in burrows in dead wood, bamboo, or structural timbers (except those in the subgenus Proxylocopa, which nest in the ground). Members of the related tribe Ceratinini are sometimes referred to as "small carpenter bees".
The genus was described by French entomologist Pierre André Latreille in 1802. The name is derived from the Ancient Greek xylokopos/ξῦλοκὀπος "wood-cutter".
In several species, the females live alongside their own daughters or sisters, creating a small social group. They use wood bits to form partitions between the cells in the nest. A few species bore holes in wood dwellings. Since the tunnels are near the surface, structural damage is generally minor or nonexistent.
Carpenter bees can be important pollinators on open-faced flowers, even obligate pollinators on some, such as the Maypop (Passiflora incarnata), though many species are also known to "rob" nectar by slitting the sides of flowers with deep corollas.
In the United States, there are two eastern species, Xylocopa virginica, and Xylocopa micans, and three other species that are primarily western in distribution, Xylocopa varipuncta, Xylocopa tabaniformis orpifex and Xylocopa californica. X. virginica is by far the more widely distributed species. Some are often mistaken for a bumblebee species, as they can be similar in size and coloration, though most carpenter bees have a shiny abdomen, while in bumblebees the abdomen is completely clothed with dense hair. Males of some species have a white or yellow face, where the females do not; males also often have much larger eyes than the females, which relates to their mating behavior. Male bees are often seen hovering near nests, and will approach nearby animals. However, males are harmless, since they do not have a stinger. Female carpenter bees are capable of stinging, but they are docile and rarely sting unless caught in the hand or otherwise directly provoked.
Many Old World carpenter bees have a special pouch-like structure on the inside of their first metasomal tergite called the acarinarium where certain species of mites (Dinogamasus spp.) reside as commensals. The exact nature of the relationship is not fully understood, though in other bees that carry mites, the mites are beneficial, feeding either on fungi in the nest, or on other, harmful mites.
Carpenter bees are traditionally considered solitary bees, though some species have simple social nests in which mothers and daughters may cohabit. However, even solitary species tend to be gregarious, and often several will nest near each other. It has been occasionally reported that when females cohabit, there may be a division of labor between them, where one female may spend most of her time as a guard within the nest, motionless and near the entrance, while another female spends most of her time foraging for provisions.
Carpenter bees make nests by tunneling into wood, vibrating their bodies as they rasp their mandibles against the wood, each nest having a single entrance which may have many adjacent tunnels. The entrance is often a perfectly circular hole measuring about 16 millimetres (0.63 in) on the underside of a beam, bench, or tree limb. Carpenter bees do not eat wood. They discard the bits of wood, or re-use particles to build partitions between cells. The tunnel functions as a nursery for brood and storage for the pollen/nectar upon which the brood subsists. The provision masses of some species are among the most complex in shape of any group of bees; whereas most bees fill their brood cells with a soupy mass, and others form simple spheroidal pollen masses, Xylocopa form elongate and carefully sculpted masses that have several projections which keep the bulk of the mass from coming into contact with the cell walls, sometimes resembling an irregular caltrop. The eggs are very large relative to the size of the female, and are some of the largest eggs among all insects.
There are two very different mating systems that appear to be common in carpenter bees, and often this can be determined simply by examining specimens of the males of any given species. Species in which the males have large eyes are characterized by a mating system where the males either search for females by patrolling, or by hovering and waiting for passing females, whom they then pursue. In the other type of mating system, the males often have very small heads, but there is a large, hypertrophied glandular reservoir in the mesosoma, which releases pheromones into the airstream behind the male while it flies or hovers. The pheromone advertises the presence of the male to females.
The Megachilidae are a cosmopolitan family of (mostly) solitary bees whose pollen-carrying structure (called a scopa) is restricted to the ventral surface of the abdomen (rather than mostly or exclusively on the hind legs as in other bee families).
Megachilid genera are most commonly known as mason bees and leafcutter bees, reflecting the materials they build their nest cells from (soil or leaves, respectively); a few collect plant or animal hairs and fibers, and are called carder bees. All species feed on nectar and pollen, but a few are cleptoparasites (informally called "cuckoo bees"), feeding on pollen collected by other megachilid bees. Parasitic species do not possess scopae. The brightly colored scopa leads to a colloquial name used occasionally in North America - "jelly-belly bees".][ Megachilid bees are among the world's most efficient pollinators because of their energetic swimming-like motion in the reproductive structures of flowers, which moves pollen, as needed for pollination. One of the reasons they are efficient pollinators is their frequency of visits to plants, but this is because they are extremely inefficient at gathering pollen; compared to all other bee families, megachilids require on average nearly 10 times as many trips to flowers to gather sufficient resources to provision a single brood cell.
North America has many native megachilid species, but alfalfa leafcutter bees (Megachile rotundata) are an imported species used for pollination. The most significant native species is Osmia lignaria (the orchard mason bee or blue orchard bee), which is sold commercially for use in orchard crop pollination, and which can be attracted to nest in wooden blocks with holes drilled in them (which are also sold commercially for this purpose).
The general life cycle of nonparasitic Megachilidae generally is:
Some genera of Megachilids are brood parasites and, therefore, have no ventral scopa (e.g. Stelis and Coelioxys). They often parasitize related taxa. They typically enter the nest before it is sealed and lay their eggs in a cell. After hatching, the parasite larva kills the host larva, unless the female parasite has already done so, and then consumes the provisions. Parasitic species are of equal size or smaller than their victims.
The pollen basket or corbicula is part of the tibia on the hind legs of the four related lineages of apid bees that used to compose the family Apidae: the honey bees, bumblebees, stingless bees, and orchid bees. The corbicula ("little basket") is a polished cavity surrounded by a fringe of hairs, into which the pollen is placed; most other bees possess a structure called the scopa, which is similar in function, but is a dense mass of branched hairs into which pollen is pressed, with pollen grains held in place in the narrow spaces between the hairs. A honey bee moistens the forelegs with a protruding tongue and brushes the pollen that has collected on head, body and forward appendages to the hind legs. The pollen is transferred to the pollen comb on the hind legs and then combed, pressed, compacted, and transferred to the corbicula on the outside surface of the tibia of the hind legs. A single hair functions as a pin that secures the middle of the pollen load. Honey and/or nectar is used to moisten the dry pollen, producing the product known as bee pollen or bee bread. The mixing of the pollen with nectar or honey changes the color of the pollen. The color of the pollen can identify the pollen source.
Karl von Frisch and other bee researchers have observed that individual honey bees vary in their efficiency in packing pollen into the pollen basket; some are more efficient, others less. It takes an individual worker bee from three to eighteen minutes to complete a pollen load and return to the hive.
Mass provisioning is a term used in entomology to refer to a form of parental behavior in which an adult (most commonly a hymenopteran such as a bee or wasp) stocks all of the food for each offspring in a small chamber (a "cell") prior to laying the egg. In such cases, the food is typically in the form of paralyzed or dead prey items (in predatory wasps), or masses of mixed pollen and nectar (in bees); only rarely are other sorts of food resources used (such as floral oils, leaves, dung, or carrion). The most well-known examples from outside the Hymenoptera are various lineages of dung beetles, which typically provision with either leaves or dung. Once the provisions are in place and the egg is laid, the cell is almost invariably sealed, to protect the developing brood (Wilson, E.O. 1971).
In a few extreme cases, such as stingless bees (which are eusocial), the number of cells in a single nest can number in the thousands, but more typically a given nest will contain either a single cell, or only a small number (fewer than 10) (Wilson, E.O. 1971).
Many of the more well-known eusocial insects, such as ants and honey bees, practice progressive provisioning, where the larvae are fed directly and continually during their development (Wilson, E.O. 1971).
Wilson, E.O. (1971) The Insect Societies. Harvard, Belknap Press.
>300 species, including
Mason bee is a common name for species of bees in the genus Osmia, of the family Megachilidae. They are named from their habit of making compartments of mud in their nests, which are made in hollow reeds or holes in wood made by wood-boring insects.
A bumblebee is any member of the bee genus Bombus, in the family Apidae. There are over 250 known species, existing primarily in the Northern Hemisphere although they also occur in South America. They have been introduced to New Zealand and the Australian state of Tasmania.
Bumblebees are social insects that are characterised by black and yellow body hairs, often in bands. However, some species have orange or red on their bodies, or may be entirely black. Another obvious (but not unique) characteristic is the soft nature of the hair (long, branched setae), called pile, that covers their entire body, making them appear and feel fuzzy. They are best distinguished from similarly large, fuzzy bees by the form of the female hind leg, which is modified to form a corbicula: a shiny concave surface that is bare, but surrounded by a fringe of hairs used to transport pollen (in similar bees, the hind leg is completely hairy, and pollen grains are wedged into the hairs for transport).
The Megachilidae are a cosmopolitan family of (mostly) solitary bees whose pollen-carrying structure (called a scopa) is restricted to the ventral surface of the abdomen (rather than mostly or exclusively on the hind legs as in other bee families).
Plant reproduction is the production of new individuals or offspring in plants, which can be accomplished by sexual or asexual means. Sexual reproduction produces offspring by the fusion of gametes, resulting in offspring genetically different from the parent or parents. Asexual reproduction produces new individuals without the fusion of gametes, genetically identical to the parent plants and each other, except when mutations occur. In seed plants, the offspring can be packaged in a protective seed, which is used as an agent of dispersal.