A simple eye or ocellus (sometimes called a pigment pit ) is a form of eye or an optical arrangement which has a single lens without the sort of elaborate retina that occurs in most vertebrates . These eyes are called "simple" to distinguish them from " compound eyes ", which have multiple lenses. They are not necessarily simple in the sense of being uncomplicated or basic.
74-562: Halictidae is the second-largest family of bees (clade Anthophila ) with nearly 4,500 species. They are commonly called sweat bees (especially the smaller species), as they are often attracted to perspiration . Halictid species are an extremely diverse group that can vary greatly in appearance. These bees occur all over the world and are found on every continent except Antarctica. Usually dark-colored (frequently brown or black) and often metallic, halictids are found in various sizes, colors and patterns. Several species are all or partly green and
148-401: A division of labour into reproductive and non-reproductive adults, plus overlapping generations. This division of labour creates specialized groups within eusocial societies which are called castes . In some species, groups of cohabiting females may be sisters, and if there is a division of labour within the group, they are considered semisocial . The group is called eusocial if, in addition,
222-663: A bee, be it a solitary or social species, involves the laying of an egg, the development through several moults of a legless larva , a pupation stage during which the insect undergoes complete metamorphosis , followed by the emergence of a winged adult. The number of eggs laid by a female during her lifetime can vary from eight or less in some solitary bees, to more than a million in highly social species. Most solitary bees and bumble bees in temperate climates overwinter as adults or pupae and emerge in spring when increasing numbers of flowering plants come into bloom. The males usually emerge first and search for females with which to mate. Like
296-431: A class of simple eyes. Many kinds of holometabolous larvae bear no other form of eyes until they enter their final stage of growth. Adults of several orders of hexapods also have stemmata, and never develop compound eyes at all. Examples include fleas , springtails , and Thysanura . Some other Arthropoda , such as some Myriapoda , rarely have any eyes other than stemmata at any stage of their lives (exceptions include
370-413: A clue to their ontogenetic role is their lateral position on the head; ocelli, that in other ways resemble stemmata, tend to be borne in sites median to the compound eyes, or nearly so. Among some researchers, this distinction has led to the use of the term "lateral ocelli" for stemmata. A number of genetic pathways are responsible for the occurrence and positioning of the ocelli. The gene orthodenticle
444-429: A compartment (a "cell") with an egg and some provisions for the resulting larva, then seals it off. A nest may consist of numerous cells. When the nest is in wood, usually the last (those closer to the entrance) contain eggs that will become males. The adult does not provide care for the brood once the egg is laid, and usually dies after making one or more nests. The males typically emerge first and are ready for mating when
518-452: A distinct retina, lens, and cornea. Many snails and slugs also have ocelli, either at the tips or bases of their tentacles. Some other gastropods, such as the Strombidae , have much more sophisticated eyes. Giant clams have ocelli that allow light to penetrate their mantles . Spiders do not have compound eyes, but instead have several pairs of simple eyes with each pair adapted for
592-466: A distinct set of genera which are commonly known by their nesting behavior or preferences, namely: carpenter bees, sweat bees , mason bees, plasterer bees , squash bees , dwarf carpenter bees , leafcutter bees, alkali bees and digger bees . Most solitary bees are fossorial , digging nests in the ground in a variety of soil textures and conditions, while others create nests in hollow reeds or twigs, or holes in wood . The female typically creates
666-409: A family of sawflies) are only "simple" in that they represent immature or embryonic forms of the compound eyes of the adult. They can possess a considerable degree of acuity and sensitivity, and can detect polarized light. They may be optimized for light sensitivity, as opposed to detailed image formation. In the pupal stage, such stemmata develop into fully fledged compound eyes. One feature offering
740-403: A few are red, purple, or blue. A number of them have yellow markings, especially the males, which commonly have yellow faces, a pattern widespread among the various families of bees. The family is one of many with short tongues and is best distinguished by the arcuate (strongly curved) basal vein found on the wing. Females in this family tend to be larger than the males. They are the group for which
814-545: A larva is fed repeatedly as it grows, as in honey bees . Some species line their tunnels with lactone secretions to help workers return to the nest. It is thought that each individual bee has its own unique chemical signature. All species (except for kleptoparasites ) are pollen feeders and may be important pollinators . Many species in the Halictidae are eusocial at least in part, such as Lasioglossum malachurum , with fairly well-defined queen and worker castes (though not
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#1732845687695888-525: A larva's food is supplied gradually as it develops, as is the case in honey bees and some bumblebees. Most other bees, including familiar insects such as carpenter bees , leafcutter bees and mason bees are solitary in the sense that every female is fertile, and typically inhabits a nest she constructs herself. There is no division of labor so these nests lack queens and worker bees for these species. Solitary bees typically produce neither honey nor beeswax . Bees collect pollen to feed their young, and have
962-440: A length of 39 millimetres (1.54 in). Bees feed on nectar and pollen , the former primarily as an energy source and the latter primarily for protein and other nutrients. Most pollen is used as food for their larvae . Vertebrate predators of bees include primates and birds such as bee-eaters ; insect predators include beewolves and dragonflies . Bee pollination is important both ecologically and commercially , and
1036-729: A male is haploid (has only one copy of each gene), his daughters (which are diploid , with two copies of each gene) share 100% of his genes and 50% of their mother's. Therefore, they share 75% of their genes with each other. This mechanism of sex determination gives rise to what W. D. Hamilton termed "supersisters", more closely related to their sisters than they would be to their own offspring. Workers often do not reproduce, but they can pass on more of their genes by helping to raise their sisters (as queens) than they would by having their own offspring (each of which would only have 50% of their genes), assuming they would produce similar numbers. This unusual situation has been proposed as an explanation of
1110-404: A number of neighbouring retinulae. Some jellyfish , sea stars , flatworms , and ribbonworms have the simplest "eyes" – pigment spot ocelli – which have randomly distributed pigment, and which have no other structure (such as a cornea , or lens ). The apparent "eye color" in these animals is red or black. Certain groups such as box jellyfish have more complex eyes, including some with
1184-438: A permanent, rigid, division of labor, such as Lasioglossum zephyrus or Halictus rubicundus , are considered primitively eusocial. Another example of a primitive eusocial bee species from this family is Halictus ligatus , for which aggression is one of the most influential behavioral attitudes for establishing hierarchy and social organization within the colony. Primitively eusocial species such as these provide insight into
1258-533: A single season colony cycle, even in the tropics, and only mated females hibernate. A few species have long active seasons and attain colony sizes in the hundreds, such as Halictus hesperus . Some species are eusocial in parts of their range and solitary in others, or have a mix of eusocial and solitary nests in the same population. The orchid bees (Apidae) include some primitively eusocial species with similar biology. Some allodapine bees (Apidae) form primitively eusocial colonies, with progressive provisioning :
1332-409: A specific task or tasks. The principal and secondary eyes in spiders are arranged in four, or occasionally fewer, pairs. Only the principal eyes have moveable retinas. The secondary eyes have a reflector at the back of the eyes. The light-sensitive part of the receptor cells is next to this, so they get direct and reflected light. In hunting or jumping spiders, for example, a forward-facing pair possesses
1406-506: Is Cretotrigona prisca , a corbiculate bee of Late Cretaceous age (~70 mya) found in New Jersey amber . A fossil from the early Cretaceous (~100 mya), Melittosphex burmensis , was initially considered "an extinct lineage of pollen-collecting Apoidea sister to the modern bees", but subsequent research has rejected the claim that Melittosphex is a bee, or even a member of the superfamily Apoidea to which bees belong, instead treating
1480-445: Is absent. The sideways-facing ocelli can be called "lateral ocelli", referring to their direction and position in the triplet, however this is not to be confused with the stemmata of some insect larvae, which are also known as lateral ocelli. A dorsal ocellus consists of a lens element ( cornea ) and a layer of photoreceptors ( rod cells ). The ocellar lens may be strongly curved or flat. The photoreceptor layer may also be separated from
1554-506: Is allelic to ocelliless, a mutation that stops ocelli from being produced. In Drosophila , the rhodopsin Rh2 is only expressed in simple eyes. While (in Drosophila at least) the genes eyeless and dachshund are both expressed in the compound eye but not the simple eye, no reported 'developmental' genes are uniquely expressed in the simple eye. Epidermal growth factor receptor ( Egfr ) promotes
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#17328456876951628-470: Is believed that mites eat fungi that attack pollen, so the relationship in this case may be mutualistic . Molecular phylogeny was used by Debevic et al , 2012, to demonstrate that the bees ( Anthophila ) arose from deep within the Crabronidae sensu lato , which was thus rendered paraphyletic . In their study, the placement of the monogeneric Heterogynaidae was uncertain. The small family Mellinidae
1702-412: Is determined by the environment in which it lives, and the behavioural tasks it must fulfill to survive. Arthropods differ widely in the habitats in which they live, as well as their visual requirements for finding food or conspecifics , and avoiding predators. Consequently, an enormous variety of eye types are found in arthropods to overcome visual problems or limitations. Use of the term simple eye
1776-609: Is flexible, and must be interpreted in proper context; for example, the eyes of most large animals are camera eyes and are sometimes considered "simple" because a single lens collects and focuses an entire image onto the retina (analogous to a camera ). By other criteria, the presence of a complex retina distinguishes the vertebrate camera eye from the simple stemma or ommatidia which make up compound eyes. Additionally, not all invertebrate ocelli and ommatidium have simple photoreceptors . Many have various forms of retinula (a retina-like cluster of photoreceptor cells), including
1850-444: Is the ancestral state for all eusocial species so far investigated, so it is likely that haplodiploidy contributed to the evolution of eusociality in bees. Bees may be solitary or may live in various types of communities. Eusociality appears to have originated from at least three independent origins in halictid bees. The most advanced of these are species with eusocial colonies; these are characterised by cooperative brood care and
1924-542: Is thought to have occurred due to rapid climatic cooling around the Eocene-Oligocene boundary , leading to the extinction of some bee lineages such as the tribe Melikertini . Over the Paleogene and Neogene , different bee lineages continued to spread all over the world, and the shifting habitats and connectedness of continents led to the isolation and evolution of many new bee tribes. The oldest non-compression bee fossil
1998-552: The Baltic Region and the Dominican Republic and imply that Halictidae have existed since at least 96-75 million years ago. The oldest fossil record of Halictidae dates back to Early Eocene with a number of species, such as Neocorynura electra and Augochlora leptoloba known from amber deposits. Currently, the family is divided into four subfamilies, many genera, and more than 2000 known species. Rophitinae appears to be
2072-533: The Early Cretaceous (about 124 million years ago) on the supercontinent of West Gondwana , just prior to its breakup into South America and Africa . The supercontinent is thought to have been a largely xeric environment at this time; modern bee diversity hotspots are also in xeric and seasonal temperate environments, suggesting strong niche conservatism among bees ever since their origins. Genomic analysis indicates that despite only appearing much later in
2146-674: The Stenotritidae ), and by the end of the Cretaceous, South American bees had also colonized North America. The North American fossil taxon Cretotrigona belongs to a group that is no longer found in North America, suggesting that many bee lineages went extinct during the Cretaceous-Paleogene extinction event . Following the K-Pg extinction, surviving bee lineages continued to spread into
2220-570: The Bumblebee Specialist Group to review the threat status of all bumblebee species worldwide using the IUCN Red List criteria. There are many more species of primitively eusocial than highly eusocial bees, but they have been studied less often. Most are in the family Halictidae , or "sweat bees". Colonies are typically small, with a dozen or fewer workers, on average. Queens and workers differ only in size, if at all. Most species have
2294-577: The Eocene-Oligocene boundary, around 34 Mya, of the Florissant shale. The Halictidae first appear in the Early Eocene with species found in amber. The Stenotritidae are known from fossil brood cells of Pleistocene age. The earliest animal-pollinated flowers were shallow, cup-shaped blooms pollinated by insects such as beetles , so the syndrome of insect pollination was well established before
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2368-574: The Northern Hemisphere, colonizing Europe from Africa by the Paleocene , and then spreading east to Asia . This was facilitated by the warming climate around the same time, allowing bees to move to higher latitudes following the spread of tropical and subtropical habitats. By the Eocene (~45 mya) there was already considerable diversity among eusocial bee lineages. A second extinction event among bees
2442-488: The appearance of being social. Large groups of solitary bee nests are called aggregations , to distinguish them from colonies . In some species, multiple females share a common nest, but each makes and provisions her own cells independently. This type of group is called "communal" and is not uncommon. The primary advantage appears to be that a nest entrance is easier to defend from predators and parasites when multiple females use that same entrance regularly. The life cycle of
2516-842: The bee families is based on Hedtke et al., 2013, which places the former families Dasypodaidae and Meganomiidae as subfamilies inside the Melittidae. English names, where available, are given in parentheses. Melittidae (inc. Dasypodainae , Meganomiinae ) at least 50 Mya [REDACTED] Apidae (inc. honeybees, cuckoo bees, carpenter bees) ≈87 Mya [REDACTED] Megachilidae (mason, leafcutter bees) ≈50 Mya [REDACTED] Andrenidae (mining bees) ≈34 Mya [REDACTED] Halictidae (sweat bees) ≈50 Mya [REDACTED] Colletidae (plasterer bees) ≈25 Mya [REDACTED] Stenotritidae (large Australian bees) ≈2 Mya [REDACTED] Bees differ from closely related groups such as wasps by having branched or plume-like setae (hairs), combs on
2590-671: The best known insects. Their colonies are established by swarms , consisting of a queen and several thousand workers. There are 29 subspecies of one of these species, Apis mellifera , native to Europe, the Middle East, and Africa. Africanized bees are a hybrid strain of A. mellifera that escaped from experiments involving crossing European and African subspecies; they are extremely defensive. Stingless bees are also highly eusocial . They practise mass provisioning , with complex nest architecture and perennial colonies also established via swarming. Many bumblebees are eusocial, similar to
2664-634: The best resolution (and even some telescopic ability) to help spot prey from a distance. Nocturnal spiders' eyes are very sensitive in low light levels and are large to capture more light, equivalent to f/0.58 in the rufous net-casting spider . The term "ocellus" (plural ocelli) is derived from the Latin oculus (eye), and literally means "little eye". In insects, two distinct ocellus types exist: dorsal (top-most) ocelli, and lateral ocelli (often referred to as ocelli and stemmata , respectively), most insects have dorsal ocelli while stemmata are found in
2738-674: The case of the best-known bee species, the western honey bee , for producing honey . Bees are a monophyletic lineage within the superfamily Apoidea . They are currently considered a clade , called Anthophila . There are over 20,000 known species of bees in seven recognized biological families . Some species – including honey bees , bumblebees , and stingless bees – live socially in colonies while most species (>90%) – including mason bees , carpenter bees , leafcutter bees , and sweat bees – are solitary. Bees are found on every continent except Antarctica , in every habitat on
2812-585: The compound eyes. Additionally, given the relatively simple neural arrangement of the eye (small number of synapses between detector and effector ), as well as the extremely large diameter of some ocellar interneurons (often the largest diameter neurons in the animal's nervous system), the ocelli are typically considered to be "faster" than the compound eyes. One common theory of ocellar function in flying insects holds that they are used to assist in maintaining flight stability. Given their underfocused nature, wide fields of view , and high light-collecting ability,
2886-405: The conclusion that, with some exceptions in predatory insects, the ocelli are incapable of perceiving proper images and are thus solely suitable for light-metering functions. Given the large aperture and low f -number of the lens, as well as high convergence ratios and synaptic gains (amplification of photoreceptor signals), the ocelli are generally considered to be far more sensitive to light than
2960-401: The decline in wild bees has increased the value of pollination by commercially managed hives of honey bees. The analysis of 353 wild bee and hoverfly species across Britain from 1980 to 2013 found the insects have been lost from a quarter of the places they inhabited in 1980. Human beekeeping or apiculture ( meliponiculture for stingless bees) has been practised for millennia, since at least
3034-412: The dorsal ocelli vary markedly throughout insect orders. They tend to be larger and more strongly expressed in flying insects (particularly bees, wasps, dragonflies and locusts) where they are typically found as a triplet. Two ocelli are directed to either side of the head, while a central (median) ocellus is directed forwards. In some terrestrial insects (e.g. some ants and cockroaches), the median ocellus
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3108-426: The early evening, so are technically considered " vespertine " (e.g. in the subgenus Sphecodogastra of Lasioglossum ), or sometimes truly nocturnal (e.g. in the genus Megalopta , such as the species M. genalis ). These bees, as is typical in such cases, have greatly enlarged ocelli . The other families with some crepuscular species are Andrenidae , Colletidae , and Apidae . Some Halictids are important in
3182-540: The early evolution of eusociality. Halictus sexcinctus , which exhibits social, communal, and eusocial organization, provides insight into the evolutionary reversal of eusociality. Phylogenetic data from this species suggests that a communal strategy serves as a transitional step between eusociality and a reversion back to solitary nesting. Several genera and species of halictids are kleptoparasites of other bees (mostly other halictids or bees of similar size). The behavior has evolved at least nine times independently within
3256-478: The eusocial Vespidae such as hornets in that the queen initiates a nest on her own rather than by swarming. Bumblebee colonies typically have from 50 to 200 bees at peak population, which occurs in mid to late summer. Nest architecture is simple, limited by the size of the pre-existing nest cavity, and colonies rarely last more than a year. In 2011, the International Union for Conservation of Nature set up
3330-402: The exceptional acrobatic abilities of these animals. Research on the ocelli is of high interest to designers of small unmanned aerial vehicles . Designers of these craft face many of the same challenges that insects face in maintaining stability in a three-dimensional world. Engineers are increasingly taking inspiration from insects to overcome these challenges. Stemmata (singular stemma) are
3404-480: The family Crabronidae , which were predators of other insects. The switch from insect prey to pollen may have resulted from the consumption of prey insects which were flower visitors and were partially covered with pollen when they were fed to the wasp larvae. This same evolutionary scenario may have occurred within the vespoid wasps, where the pollen wasps evolved from predatory ancestors. Based on phylogenetic analysis, bees are thought to have originated during
3478-488: The family. The most well-known and common are species in the genus Sphecodes , which are somewhat wasp -like in appearance (often shining black with blood-red abdomen- German: Blutbienen - usually 4–9 mm in body length); the female Sphecodes enters the cell with the provision mass, eats the host egg, and lays an egg of her own in its place. Halictidae is one of the four bee families that contain some crepuscular species; these halictids are active only at dusk or in
3552-521: The females emerge. Solitary bees are very unlikely to sting (only in self-defense, if ever), and some (esp. in the family Andrenidae ) are stingless. While solitary, females each make individual nests. Some species, such as the European mason bee Hoplitis anthocopoides , and the Dawson's Burrowing bee , Amegilla dawsoni, are gregarious, preferring to make nests near others of the same species, and giving
3626-605: The first appearance of bees. The novelty is that bees are specialized as pollination agents, with behavioral and physical modifications that specifically enhance pollination, and are the most efficient pollinating insects. In a process of coevolution , flowers developed floral rewards such as nectar and longer tubes, and bees developed longer tongues to extract the nectar. Bees also developed structures known as scopal hairs and pollen baskets to collect and carry pollen. The location and type differ among and between groups of bees. Most species have scopal hairs on their hind legs or on
3700-470: The forelimbs for cleaning their antennae, small anatomical differences in limb structure, and the venation of the hind wings; and in females, by having the seventh dorsal abdominal plate divided into two half-plates. Bees have the following characteristics: The largest species of bee is thought to be Wallace's giant bee Megachile pluto , whose females can attain a length of 39 millimetres (1.54 in). The smallest species may be dwarf stingless bees in
3774-456: The fossil record, all modern bee families had already diverged from one another by the end of the Cretaceous. The Melittidae , Apidae , and Megachilidae had already evolved on the supercontinent prior to its fragmentation. Further divergences were facilitated by West Gondwana's breakup around 100 million years ago, leading to a deep Africa-South America split within both the Apidae and Megachilidae,
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#17328456876953848-464: The group consists of a mother (the queen ) and her daughters ( workers ). When the castes are purely behavioural alternatives, with no morphological differentiation other than size, the system is considered primitively eusocial, as in many paper wasps ; when the castes are morphologically discrete, the system is considered highly eusocial. True honey bees (genus Apis , of which eight species are currently recognized) are highly eusocial, and are among
3922-636: The isolation of the Melittidae in Africa, and the origins of the Colletidae , Andrenidae and Halictidae in South America. The rapid radiation of the South American bee families is thought to have followed the concurrent radiation of flowering plants in the same region. Later in the Cretaceous (80 million years ago), colletid bees colonized Australia from South America (with an offshoot lineage evolving into
3996-420: The large and well-developed compound eyes of the house centipedes, Scutigera ). Behind each lens of a typical functional stemma lies a single cluster of photoreceptor cells, termed a retinula. The lens is biconvex , and the body of the stemma has a vitreous or crystalline core. Although stemmata are simple eyes, some kinds (such as those of the larvae of Lepidoptera and especially those of Tenthredinidae ,
4070-768: The larvae of some insect orders. Despite the shared name, they are structurally and functionally very different. Simple eyes of other animals may also be referred to as ocelli, but again the structure and anatomy of these eyes is quite distinct from those of insect dorsal ocelli. Dorsal ocelli are light-sensitive organs found on the dorsal surface or frontal surface of the head of many insects, including Hymenoptera ( bees , ants , wasps , sawflies ), Diptera (flies), Odonata ( dragonflies , damselflies ), Orthoptera ( grasshoppers , locusts ) and Mantodea (mantises). These ocelli coexist with compound eyes; thus, most insects possess two anatomically separate and functionally different visual pathways. The number, forms, and functions of
4144-470: The lens by a clear vitreous humour . The number of photoreceptors also varies widely, but may number in the hundreds or thousands for well-developed ocelli. In bees, locusts, and dragonflies, the lens is strongly curved; while in cockroaches it is flat. Locusts possess vitreous humour while blowflies and dragonflies do not. Two somewhat unusual features of ocelli are particularly notable and generally common between insect orders. These two factors have led to
4218-639: The lineage as incertae sedis within the Aculeata . The Allodapini (within the Apidae) appeared around 53 Mya. The Colletidae appear as fossils only from the late Oligocene (~25 Mya) to early Miocene . The Melittidae are known from Palaeomacropis eocenicus in the Early Eocene . The Megachilidae are known from trace fossils (characteristic leaf cuttings) from the Middle Eocene . The Andrenidae are known from
4292-495: The multiple (at least nine) evolutions of eusociality within Hymenoptera . Haplodiploidy is neither necessary nor sufficient for eusociality. Some eusocial species such as termites are not haplodiploid. Conversely, all bees are haplodiploid but not all are eusocial, and among eusocial species many queens mate with multiple males, creating half-sisters that share only 25% of each other's genes. But, monogamy (queens mating singly)
4366-565: The necessary adaptations to do this. However, certain wasp species such as pollen wasps have similar behaviours, and a few species of bee scavenge from carcases to feed their offspring. Solitary bees are important pollinators; they gather pollen to provision their nests with food for their brood. Often it is mixed with nectar to form a paste-like consistency. Some solitary bees have advanced types of pollen-carrying structures on their bodies. Very few species of solitary bee are being cultured for commercial pollination. Most of these species belong to
4440-488: The ocelli are superbly adapted for measuring changes in the perceived brightness of the external world as an insect rolls or pitches around its body axis during flight. Locusts and dragonflies in tethered flight have been observed to try and "correct" their flight posture based on changes in light. Other theories of ocellar function have ranged from roles as light adaptors or global excitatory organs to polarization sensors and circadian entrainers . Recent studies have shown
4514-442: The ocelli of some insects (most notably the dragonfly, but also some wasps) are capable of "form vision" similar to camera eyes, as the ocellar lens forms an image within, or close to, the photoreceptor layer. In dragonflies it has been demonstrated that the receptive fields of both the photoreceptors and the second-order neurons can be quite restricted. Further research has demonstrated these eyes not only resolve spatial details of
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#17328456876954588-403: The ommatidia of most insects and the central eyes of camel spiders . Jumping spiders and some other predatory spiders with seemingly simple eyes also emulate retinal vision in various ways. Many insects have unambiguously compound eyes consisting of multiple lenses (up to tens of thousands), but achieve an effect similar to that of a camera eye, in that each ommatidium lens focuses light onto
4662-454: The other members of Hymenoptera bees are haplodiploid ; the sex of a bee is determined by whether or not the egg is fertilised. After mating, a female stores the sperm, and determines which sex is required at the time each individual egg is laid, fertilised eggs producing female offspring and unfertilised eggs, males. Tropical bees may have several generations in a year and no diapause stage. Ocelli The structure of an animal's eye
4736-532: The planet that contains insect-pollinated flowering plants . The most common bees in the Northern Hemisphere are the Halictidae , or sweat bees, but they are small and often mistaken for wasps or flies. Bees range in size from tiny stingless bee species, whose workers are less than 2 millimetres (0.08 in) long, to the leafcutter bee Megachile pluto , the largest species of bee, whose females can attain
4810-456: The pollination of crops. Among these are the alkali bee , Lasioglossum vierecki and Lasioglossum leucozonium . While some halictid species are oligoleges (e.g., Rophites algirus which only visits the flowers of hedgenettle plants.), most are generalists making them potentially valuable overall pollinators. Only females have the ability to deliver a sting. Due to their non-aggressive nature, they are only likely to sting if disturbed;
4884-582: The same as the caste system in honey bees ), and certain manifestations of their social behavior appear to be facultative in various lineages. The first group of offspring continues to build and protect the nest as well as gather food for a new brood of larvae. An impressive variety of social and nesting behaviors are exhibited by halictids including solitary, communal, semi-social and primitively eusocial. Different biotic and abiotic factors can even affect these behaviors such as floral resources, location, altitude, season, and climate. Those species which do not have
4958-499: The sister group to the remaining three subfamilies (Nomiinae, Nomioidinae, Halictinae ) based on both morphology and molecular data. Subfamily Rophitinae : Subfamily Nomiinae : Subfamily Nomioidinae : Subfamily Halictinae : Tribe Halictini Tribe Thrinchostomini Tribe Augochlorini Unplaced fossil halictines: Bees Apiformes (from Latin 'apis' ) Bees are winged insects closely related to wasps and ants , known for their roles in pollination and, in
5032-417: The sting is minor. The most common instances of stinging occur from swatting at or accidentally making contact with a halictid trying to get a lick of one's sweat, seeking the dissolved electrolytes. Halictidae belongs to the hymenopteran subclade Aculeata (stinging Hymenoptera), superfamily Apoidea (bees and wasps), series Anthophila (true bees). Fossils from this family are typically found in amber from
5106-428: The term 'eusocial' was first coined by entomologist, Suzanne Batra . Most halictids nest in the ground, often in habitats like clay soil and river banks, though a few nest in wood. They mass-provision their young; a mass of pollen and nectar is formed inside a waterproof cell, an egg laid upon it, and the cell sealed off, so the larva is given all of its food at one time, as opposed to "progressive provisioning", where
5180-488: The times of Ancient Egypt and Ancient Greece . Bees have appeared in mythology and folklore, through all phases of art and literature from ancient times to the present day, although primarily focused in the Northern Hemisphere where beekeeping is far more common. In Mesoamerica , the Mayans have practiced large-scale intensive meliponiculture since pre-Columbian times. The immediate ancestors of bees were stinging wasps in
5254-604: The tribe Meliponini whose workers are less than 2 millimetres (0.08 in) in length. According to inclusive fitness theory, organisms can gain fitness not just through increasing their own reproductive output, but also that of close relatives. In evolutionary terms, individuals should help relatives when Cost < Relatedness * Benefit . The requirements for eusociality are more easily fulfilled by haplodiploid species such as bees because of their unusual relatedness structure. In haplodiploid species, females develop from fertilized eggs and males from unfertilized eggs. Because
5328-501: The underside of their abdomens. Some species in the family Apidae have pollen baskets on their hind legs, while very few lack these and instead collect pollen in their crops. The appearance of these structures drove the adaptive radiation of the angiosperms , and, in turn, bees themselves. Bees coevolved not only with flowers but it is believed that some species coevolved with mites. Some provide tufts of hairs called acarinaria that appear to provide lodgings for mites; in return, it
5402-443: The world, but also perceive motion. Second-order neurons in the dragonfly median ocellus respond more strongly to upwards-moving bars and gratings than to downwards-moving bars and gratings, but this effect is only present when ultraviolet light is used in the stimulus; when ultraviolet light is absent, no directional response is observed. Dragonfly ocelli are especially highly developed and specialised visual organs, which may support
5476-890: Was not included in this analysis. Further studies by Sann et al. , 2018, elevated the subfamilies (plus one tribe and one subtribe) of Crabronidae sensu lato to family status. They also recovered the placement of Heterogyna within Nyssonini and sunk Heterogynaidae . The newly erected family, Ammoplanidae , formerly a subtribe of Pemphredoninae , was recovered as the most sister family to bees. Ampulicidae (Cockroach wasps) [REDACTED] Astatidae [REDACTED] Bembicidae [REDACTED] Sphecidae ( sensu stricto ) [REDACTED] Crabronidae ( sensu stricto ) [REDACTED] Mellinidae [REDACTED] Pemphredonidae [REDACTED] Philanthidae [REDACTED] Psenidae [REDACTED] Ammoplanidae Anthophila (bees) [REDACTED] This cladogram of
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