125-455: A wasp is any insect of the narrow-waisted suborder Apocrita of the order Hymenoptera which is neither a bee nor an ant ; this excludes the broad-waisted sawflies (Symphyta), which look somewhat like wasps, but are in a separate suborder. The wasps do not constitute a clade , a complete natural group with a single ancestor, as bees and ants are deeply nested within the wasps, having evolved from wasp ancestors. Wasps that are members of
250-500: A brain and a ventral nerve cord . Most insects reproduce by laying eggs . Insects breathe air through a system of paired openings along their sides, connected to small tubes that take air directly to the tissues. The blood therefore does not carry oxygen; it is only partly contained in vessels, and some circulates in an open hemocoel . Insect vision is mainly through their compound eyes , with additional small ocelli . Many insects can hear, using tympanal organs , which may be on
375-478: A multicellular organism ; castes fulfill a specific role that contributes to the functioning and survival of the whole colony, while being incapable of independent survival outside the colony. In 1969, Charles D. Michener further expanded Batra's classification with his comparative study of social behavior in bees. He observed multiple species of bees ( Apoidea ) in order to investigate the different levels of animal sociality, all of which are different stages that
500-508: A body length of only 158 micrometres, the smallest known flying insect. There are estimated to be 100,000 species of ichneumonoid wasps in the families Braconidae and Ichneumonidae . These are almost exclusively parasitoids, mostly using other insects as hosts. Another family, the Pompilidae , is a specialist parasitoid of spiders. Some wasps are even parasitoids of parasitoids; the eggs of Euceros are laid beside lepidopteran larvae and
625-429: A colony may pass through. Eusociality, which is the highest level of animal sociality a species can attain, specifically had three characteristics that distinguished it from the other levels: E. O. Wilson extended the terminology to include other social insects, such as ants, wasps, and termites. Originally, it was defined to include organisms (only invertebrates) that had the following three features: Eusociality
750-407: A colony, there are both pleated fan-shaped "nest" fronds that collect and hold water, and gutter-shaped "strap" fronds that channel water: no solitary Platycerium species has both types. At the bottom of a colony, there are "nest" fronds that clasp the trunk of the tree supporting the fern, and drooping photosynthetic fronds. These are argued to be adapted to support the colony structurally, i.e. that
875-399: A crop inside their bodies, rather than on body hairs like bees, and pollinate flowers of Penstemon and the water leaf family, Hydrophyllaceae . The Agaonidae ( fig wasps ) are the only pollinators of nearly 1000 species of figs , and thus are crucial to the survival of their host plants. Since the wasps are equally dependent on their fig trees for survival, the coevolved relationship
1000-402: A danger as the wasps may sting if people come close to them. Stings are usually painful rather than dangerous, but in rare cases, people may suffer life-threatening anaphylactic shock . Some species of parasitic wasp, especially in groups such as Aphelinidae , Braconidae , Mymaridae , and Trichogrammatidae , are exploited commercially to provide biological control of insect pests . One of
1125-480: A football club in Scotland . Wasps have been modelled in jewellery since at least the nineteenth century, when diamond and emerald wasp brooches were made in gold and silver settings. A fashion for wasp waisted female silhouettes with sharply cinched waistlines emphasizing the wearer's hips and bust arose repeatedly in the nineteenth and twentieth centuries. The Ancient Greek playwright Aristophanes wrote
1250-408: A fur-like covering of soft hairs and a special body part for pollen storage ( pollen basket ) as some bees do, pollen does not stick to them well. However it has been shown that even without hairs, several wasp species are able to effectively transport pollen, therefore contributing for potential pollination of several plant species. Pollen wasps in the subfamily Masarinae gather nectar and pollen in
1375-419: A hive of half-sisters that share only 25% of their genes. The association between haplodiploidy and eusociality is below statistical significance. Haplodiploidy is thus neither necessary nor sufficient for eusociality to emerge. Relatedness does still play a part, as monogamy (queens mating singly) is the ancestral state for all eusocial species so far investigated. If kin selection is an important force driving
SECTION 10
#17328376201271500-552: A hundred species, are marine. Insects such as snow scorpionflies flourish in cold habitats including the Arctic and at high altitude. Insects such as desert locusts , ants, beetles, and termites are adapted to some of the hottest and driest environments on earth, such as the Sonoran Desert . Insects form a clade , a natural group with a common ancestor, among the arthropods . A phylogenetic analysis by Kjer et al. (2016) places
1625-443: A hundred thousand described species around the world, and a great many more as yet undescribed. For example, almost every one of some 1000 species of tropical fig trees has its own specific fig wasp ( Chalcidoidea ) that has co-evolved with it and pollinates it. Many wasp species are parasitoids; the females deposit eggs on or in a host arthropod on which the larvae then feed. Some larvae start off as parasitoids, but convert at
1750-413: A later stage to consuming the plant tissues that their host is feeding on. In other species, the eggs are laid directly into plant tissues and form galls , which protect the developing larvae from predators, but not necessarily from other parasitic wasps. In some species, the larvae are predatory themselves; the wasp eggs are deposited in clusters of eggs laid by other insects, and these are then consumed by
1875-648: A male is haploid, his daughters 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 first termed "supersisters", more closely related to their sisters than they would be to their own offspring. Even though workers often do not reproduce, they can pass on more of their genes by helping to raise their sisters than by having their own offspring (each of which would only have 50% of their genes). This unusual situation, where females may have greater fitness when they help rear sisters rather than producing offspring,
2000-498: A mutualistic relationship with a polydnavirus that weakens the host's immune system and replicates in the oviduct of the female wasp. One family of chalcidoid wasps, the Eucharitidae , has specialized as parasitoids of ants , most species hosted by one genus of ant. Eucharitids are among the few parasitoids that have been able to overcome ants' effective defences against parasitoids. Many species of wasp, including especially
2125-618: A nearly immobile pupa . Insects that undergo three-stage metamorphosis lack a pupa, developing through a series of increasingly adult-like nymphal stages. The higher level relationship of the insects is unclear. Fossilized insects of enormous size have been found from the Paleozoic Era, including giant dragonfly-like insects with wingspans of 55 to 70 cm (22 to 28 in). The most diverse insect groups appear to have coevolved with flowering plants . Adult insects typically move about by walking and flying; some can swim. Insects are
2250-508: A pheromone, helping their nest mates to find the food. Reproductive specialization generally involves the production of sterile members of the species, which carry out specialized tasks to care for the reproductive members. Individuals may have behavior and morphology modified for group defense, including self-sacrificing behavior . For example, members of the sterile caste of the honeypot ants such as Myrmecocystus fill their abdomens with liquid food until they become immobile and hang from
2375-466: A possible resolution to the paradox might lie in the close family relationship, which W.D. Hamilton quantified a century later with his 1964 inclusive fitness theory. After the gene-centered view of evolution was developed in the mid-1970s, non-reproductive individuals were seen as an extended phenotype of the genes, which are the primary beneficiaries of natural selection. According to inclusive fitness theory, organisms can gain fitness by increasing
2500-537: A protected environment; this may be the body of a host organism or a cell in a nest, where the larva either eats the provisions left for it or, in social species, is fed by the adults. Such larvae have soft bodies with no limbs, and have a blind gut (presumably so that they do not foul their cell). Adult solitary wasps mainly feed on nectar, but the majority of their time is taken up by foraging for food for their carnivorous young, mostly insects or spiders. Apart from providing food for their larval offspring, no maternal care
2625-571: A set of pheromones that alter the behavior of specific castes in the colony. These pheromones may act across different species, as observed in Apis andreniformis (black dwarf honey bee), where worker bees responded to queen pheromone from the related Apis florea (red dwarf honey bee). Pheromones are sometimes used in these castes to assist with foraging. Workers of the Australian stingless bee Tetragonula carbonaria , for instance, mark food sources with
SECTION 20
#17328376201272750-416: A species. Multilevel selection has been heavily criticized for its conflict with the kin selection theory. A reversal to solitarity is an evolutionary phenomenon in which descendants of a eusocial group evolve solitary behavior once again. Bees have been model organisms for the study of reversal to solitarity, because of the diversity of their social systems. Each of the four origins of eusociality in bees
2875-522: A stinger for both defence and for paralysing prey. In addition to their large compound eyes , wasps have several simple eyes known as ocelli , which are typically arranged in a triangle just forward of the vertex of the head. Wasps possess mandibles adapted for biting and cutting, like those of many other insects, such as grasshoppers , but their other mouthparts are formed into a suctorial proboscis , which enables them to drink nectar. The larvae of wasps resemble maggots , and are adapted for life in
3000-399: A true brood parasite is the paper wasp Polistes sulcifer , which lays its eggs in the nests of other paper wasps (specifically Polistes dominula ), and whose larvae are then fed directly by the host. Sand wasps Ammophila often save time and energy by parasitising the nests of other females of their own species, either kleptoparasitically stealing prey, or as brood parasites, removing
3125-525: A variety of ways. Male moths can sense the pheromones of female moths over great distances. Other species communicate with sounds: crickets stridulate , or rub their wings together, to attract a mate and repel other males. Lampyrid beetles communicate with light. Humans regard many insects as pests , especially those that damage crops, and attempt to control them using insecticides and other techniques. Others are parasitic , and may act as vectors of diseases . Insect pollinators are essential to
3250-483: A weak form of eusociality. It has been suggested that the colonial and epiphytic staghorn fern , too, may make use of a primitively eusocial division of labor. The term "eusocial" was introduced in 1966 by Suzanne Batra , who used it to describe nesting behavior in Halictid bees, on a scale of subsocial/solitary, colonial/communal, semisocial, and eusocial, where a colony is started by a single individual. Batra observed
3375-477: A wide variety of prey, mainly other insects (including other Hymenoptera), both larvae and adults. The Pompilidae specialize in catching spiders to provision their nests. Some social wasps are omnivorous, feeding on fallen fruit, nectar, and carrion such as dead insects. Adult male wasps sometimes visit flowers to obtain nectar . Some wasps, such as Polistes fuscatus , commonly return to locations where they previously found prey to forage. In many social species,
3500-529: Is 50%. Therefore, helping behavior is only advantageous if it is biased to helping sisters, which would drive the population to a 1:3 sex ratio of males to females. At this ratio, males, as the rarer sex, increase in reproductive value, reducing the benefit of female-biased investment. Further, not all eusocial species are haplodiploid: termites, some snapping shrimps, and mole rats are not. Conversely, many non-eusocial bees are haplodiploid, and among eusocial species many queens mate with multiple males, resulting in
3625-506: Is a parasitoid of the Atlas beetle Chalcosoma atlas . The female giant ichneumon wasp Megarhyssa macrurus is 12.5 centimetres (5 in) long including its very long but slender ovipositor which is used for boring into wood and inserting eggs. The smallest wasps are solitary parasitoid wasps in the family Mymaridae , including the world's smallest known insect, Dicopomorpha echmepterygis (139 micrometres long) and Kikiki huna with
3750-440: Is a group of species known as tarantula hawks , along with the giant scoliid of Indonesia ( Megascolia procer ). The smallest wasps are solitary parasitoid wasps in the family Mymaridae , including the world's smallest known insect, with a body length of only 0.139 mm (0.0055 in), and the smallest known flying insect, only 0.15 mm (0.0059 in) long. Wasps have appeared in literature from Classical times , as
3875-446: Is a species of ambrosia beetle native to Australia, and is the first beetle (order Coleoptera ) to be recognized as eusocial. This species forms colonies in which a single female is fertilized, and is protected by many unfertilized females, which serve as workers excavating tunnels in trees. This species has cooperative brood care, in which individuals care for juveniles that are not their own. Some gall-inducing insects , including
Wasp - Misplaced Pages Continue
4000-427: Is an aggregation of relatives (because the shrimp do not have to disperse to find food), and much competition for those nesting sites. Being the target of attack promotes a good defense system (soldier caste); soldiers promote the fitness of the whole nest by ensuring safety and reproduction of the queen. Eusociality offers a competitive advantage in shrimp populations. Eusocial species are more abundant, occupy more of
4125-497: Is correlated with the number of females in the nest, implying that having more females leads to more efficient building and provisioning of cells. In similar species with only one queen, such as Lasioglossum malachurum in Europe, the degree of eusociality depends on the clime in which the species is found. Termites (order Blattodea , infraorder Isoptera ) make up another large portion of highly advanced eusocial animals. The colony
4250-563: Is differentiated into various castes: the queen and king are the sole reproducing individuals; workers forage and maintain food and resources; and soldiers defend the colony against ant attacks. The latter two castes, which are sterile and perform highly specialized, complex social behaviors, are derived from different stages of pluripotent larvae produced by the reproductive caste. Some soldiers have jaws so enlarged (specialized for defense and attack) that they are unable to feed themselves and must be fed by workers. Austroplatypus incompertus
4375-604: Is distinguished from all other social systems because individuals of at least one caste usually lose the ability to perform behaviors characteristic of individuals in another caste. Eusocial colonies can be viewed as superorganisms . Eusociality has evolved among the insects , crustaceans , trematoda and mammals . It is most widespread in the Hymenoptera ( ants , bees , and wasps ) and in Blattodea ( termites ). A colony has caste differences: queens and reproductive males take
4500-411: Is fully mutualistic . Most solitary wasps are parasitoids. As adults, those that do feed typically only take nectar from flowers. Parasitoid wasps are extremely diverse in habits, many laying their eggs in inert stages of their host ( egg or pupa ), sometimes paralysing their prey by injecting it with venom through their ovipositor. They then insert one or more eggs into the host or deposit them upon
4625-461: Is generally considered Russell's best novel. In Stieg Larsson 's book The Girl Who Played with Fire (2006) and its film adaptation , Lisbeth Salander has adopted her kickboxing ringname, "The Wasp", as her hacker handle and has a wasp tattoo on her neck, indicating her high status among hackers, unlike her real world situation, and that like a small but painfully stinging wasp, she could be dangerous. Parasitoidal wasps played an indirect role in
4750-487: Is given. Some wasp species provide food for the young repeatedly during their development ( progressive provisioning ). Others, such as potter wasps (Eumeninae) and sand wasps ( Ammophila , Sphecidae ), repeatedly build nests which they stock with a supply of immobilised prey such as one large caterpillar, laying a single egg in or on its body, and then sealing up the entrance ( mass provisioning ). Predatory and parasitoidal wasps subdue their prey by stinging it. They hunt
4875-626: Is involved in caring for its own offspring (except for such actions as stealing other wasps' prey or laying in other wasp's nests). There are some species of solitary wasp that build communal nests, each insect having its own cell and providing food for its own offspring, but these wasps do not adopt the division of labour and the complex behavioural patterns adopted by eusocial species. Adult solitary wasps spend most of their time in preparing their nests and foraging for food for their young, mostly insects or spiders. Their nesting habits are more diverse than those of social wasps. Many species dig burrows in
5000-542: Is not divided between castes. Though controversial, it has been suggested that male homosexuality and female menopause could have evolved through kin selection . This would mean that humans sometimes exhibit a type of alloparental behavior known as " helpers at the nest ", with juveniles and sexually mature adolescents helping their parents raise subsequent broods, as in some birds, some non-eusocial bees , and meerkats . These species are not eusocial: they do not have castes, and helpers reproduce on their own if given
5125-491: Is often invoked to explain the multiple independent evolutions of eusociality (at least nine separate times) within the Hymenoptera. Against the supposed benefits of haplodiploidy for eusociality, Robert Trivers notes that while females share 75% of genes with their sisters in haplodiploid populations, they only share 25% of their genes with their brothers. Accordingly, the average relatedness of an individual to their sibling
Wasp - Misplaced Pages Continue
5250-687: Is often reliably predicted by ecological conditions, and switches in behavioral type have been experimentally induced by translocating offspring of solitary or social populations to warm and cool climates. In H. rubicundus , females produce a single brood in cooler regions and two or more broods in warmer regions, so the former populations are solitary while the latter are social. In another species of sweat bees, L. calceatum , social phenotype has been predicted by altitude and micro-habitat composition, with social nests found in warmer, sunnier sites, and solitary nests found in adjacent, cooler, shaded locations. Facultatively social bee species, however, which comprise
5375-430: Is the highest level of organization of sociality . It is defined by the following characteristics: cooperative brood care (including care of offspring from other individuals), overlapping generations within a colony of adults , and a division of labor into reproductive and non-reproductive groups. The division of labor creates specialized behavioral groups within an animal society, sometimes called castes. Eusociality
5500-607: Is used to control the peach-potato aphid. Wasps RFC is an English professional rugby union team originally based in London but now playing in Coventry; the name dates from 1867 at a time when names of insects were fashionable for clubs. The club's first kit is black with yellow stripes. The club has an amateur side called Wasps FC . Among the other clubs bearing the name are a basketball club in Wantirna, Australia, and Alloa Athletic F.C. ,
5625-491: The Damaraland mole-rat ( Fukomys damarensis ), both of which are highly inbred . Usually living in harsh or limiting environments, these mole-rats aid in raising siblings and relatives born to a single reproductive queen. However, this classification is controversial owing to disputed definitions of 'eusociality'. To avoid inbreeding , mole rats sometimes outbreed and establish new colonies when resources are sufficient. Most of
5750-830: The Latin word insectum from in , "cut up", as insects appear to be cut into three parts. The Latin word was introduced by Pliny the Elder who calqued the Ancient Greek word ἔντομον éntomon "insect" (as in entomology ) from ἔντομος éntomos "cut in pieces"; this was Aristotle 's term for this class of life in his biology , also in reference to their notched bodies. The English word insect first appears in 1601 in Philemon Holland 's translation of Pliny. In common speech, insects and other terrestrial arthropods are often called bugs . Entomologists to some extent reserve
5875-2241: The Paraneoptera , and Kjer et al. 2016 for the Holometabola . The numbers of described extant species (boldface for groups with over 100,000 species) are from Stork 2018. Archaeognatha (hump-backed/jumping bristletails, 513 spp) [REDACTED] Zygentoma (silverfish, firebrats, fishmoths, 560 spp) [REDACTED] Odonata (dragonflies and damselflies, 5,899 spp) [REDACTED] Ephemeroptera (mayflies, 3,240 spp) [REDACTED] Zoraptera (angel insects, 37 spp) [REDACTED] Dermaptera (earwigs, 1,978 spp) [REDACTED] Plecoptera (stoneflies, 3,743 spp) [REDACTED] Orthoptera (grasshoppers, crickets, katydids, 23,855 spp) [REDACTED] Grylloblattodea (ice crawlers, 34 spp) [REDACTED] Mantophasmatodea (gladiators, 15 spp) [REDACTED] Phasmatodea (stick insects, 3,014 spp) [REDACTED] Embioptera (webspinners, 463 spp) [REDACTED] Mantodea (mantises, 2,400 spp) [REDACTED] Blattodea (cockroaches and termites, 7,314 spp) [REDACTED] Psocodea (book lice, barklice and sucking lice, 11,000 spp) [REDACTED] [REDACTED] Hemiptera (true bugs, 103,590 spp) [REDACTED] Thysanoptera (thrips, 5,864 spp) [REDACTED] Hymenoptera (sawflies, wasps, bees, ants, 116,861 spp) [REDACTED] Strepsiptera (twisted-wing flies, 609 spp) [REDACTED] Coleoptera (beetles, 386,500 spp) [REDACTED] Raphidioptera (snakeflies, 254 spp) [REDACTED] Neuroptera (lacewings, 5,868 spp) [REDACTED] Megaloptera (alderflies and dobsonflies, 354 spp) [REDACTED] Lepidoptera (butterflies and moths, 157,338 spp) [REDACTED] Trichoptera (caddisflies, 14,391 spp) [REDACTED] Diptera (true flies, 155,477 spp) [REDACTED] Mecoptera (scorpionflies, 757 spp) [REDACTED] Siphonaptera (fleas, 2,075 spp) [REDACTED] [REDACTED] [REDACTED] [REDACTED] [REDACTED] [REDACTED] [REDACTED] Eusocial Eusociality ( Greek εὖ eu "good" and social )
6000-598: The Royal Navy have been named HMS Wasp , the first an 8-gun sloop launched in 1749. Eleven ships of the United States Navy have similarly borne the name USS Wasp , the first a merchant schooner acquired by the Continental Navy in 1775. The eighth of these, an aircraft carrier , gained two Second World War battle stars, prompting Winston Churchill to remark "Who said a Wasp couldn't sting twice?" In
6125-439: The class Insecta . They are the largest group within the arthropod phylum . Insects have a chitinous exoskeleton , a three-part body ( head , thorax and abdomen ), three pairs of jointed legs , compound eyes , and a pair of antennae . Insects are the most diverse group of animals, with more than a million described species ; they represent more than half of all animal species. The insect nervous system consists of
6250-584: The comedy play Σφῆκες ( Sphēkes ), The Wasps , first put on in 422 BC. The "wasps" are the chorus of old jurors. H. G. Wells made use of giant wasps in his novel The Food of the Gods and How It Came to Earth (1904): It flew, he is convinced, within a yard of him, struck the ground, rose again, came down again perhaps thirty yards away, and rolled over with its body wriggling and its sting stabbing out and back in its last agony. He emptied both barrels into it before he ventured to go near. When he came to measure
6375-546: The cuckoo wasps , are kleptoparasites , laying eggs in the nests of other wasps. Many of the solitary wasps are parasitoidal , meaning they lay eggs on or in other insects (any life stage from egg to adult) and often provision their own nests with such hosts . Unlike true parasites, the wasp larvae eventually kill their hosts. Solitary wasps parasitize almost every pest insect , making wasps valuable in horticulture for biological pest control of species such as whitefly in tomatoes and other crops. Wasps first appeared in
SECTION 50
#17328376201276500-520: The evolution of eusocial behaviour . Females are diploid , meaning that they have 2n chromosomes and develop from fertilized eggs. Males, called drones, have a haploid (n) number of chromosomes and develop from an unfertilized egg. Wasps store sperm inside their body and control its release for each individual egg as it is laid; if a female wishes to produce a male egg, she simply lays the egg without fertilizing it. Therefore, under most conditions in most species, wasps have complete voluntary control over
6625-471: The gall -forming aphid , Pemphigus spyrothecae (order Hemiptera ), and thrips such as Kladothrips (order Thysanoptera ), are described as eusocial. These species have very high relatedness among individuals due to their asexual reproduction (sterile soldier castes being clones produced by parthenogenesis ), but the gall-inhabiting behavior gives these species a defensible resource. They produce soldier castes for fortress defense and protection of
6750-515: The gene-centered view of evolution , eusociality was seen as paradoxical: if adaptive evolution unfolds by differential reproduction of individual organisms, the evolution of individuals incapable of passing on their genes presents a challenge. In On the Origin of Species , Darwin referred to the existence of sterile castes as the "one special difficulty, which at first appeared to me insuperable, and actually fatal to my theory". Darwin anticipated that
6875-538: The head , the mesosoma (including the thorax and the first segment of the abdomen) and the metasoma. There is a narrow waist, the petiole , joining the first and second segments of the abdomen. The two pairs of membranous wings are held together by small hooks and the forewings are larger than the hind ones; in some species, the females have no wings. In females there is usually a rigid ovipositor which may be modified for injecting venom, piercing or sawing. It either extends freely or can be retracted, and may be developed into
7000-673: The Crato Formation in Brazil, some 65 million years before the first fig trees. The Vespidae include the extinct genus Palaeovespa , seven species of which are known from the Eocene rocks of the Florissant fossil beds of Colorado and from fossilised Baltic amber in Europe. Also found in Baltic amber are crown wasps of the genus Electrostephanus . Wasps are a diverse group, estimated at well over
7125-618: The Hemiptera (true bugs), Lepidoptera (butterflies and moths), Diptera (true flies), Hymenoptera (wasps, ants, and bees), and Coleoptera (beetles), each with more than 100,000 described species. Insects are distributed over every continent and almost every terrestrial habitat. There are many more species in the tropics , especially in rainforests , than in temperate zones. The world's regions have received widely differing amounts of attention from entomologists. The British Isles have been thoroughly surveyed, so that Gullan and Cranston 2014 state that
7250-862: The Second World War, a German self-propelled howitzer was named Wespe , while the British developed the Wasp flamethrower from the Bren Gun Carrier . In aerospace, the Westland Wasp was a military helicopter developed in England in 1958 and used by the Royal Navy and other navies. The AeroVironment Wasp III is a miniature UAV developed for United States Air Force special operations. Insect Insects (from Latin insectum ) are hexapod invertebrates of
7375-424: The anatomy of the worker caste, which is sterile and provides support for the reproductive caste. Most eusocial societies exist in arthropods , while a few are found in mammals . Some ferns may exhibit a primitive form of eusocial behavior. Eusociality has evolved multiple times in different insect orders, including hymenopterans, termites, thrips, aphids, and beetles. The order Hymenoptera contains
7500-452: The bird family Meropidae) specialise in eating stinging insects, making aerial sallies from a perch to catch them, and removing the venom from the stinger by repeatedly brushing the prey firmly against a hard object, such as a twig. The honey buzzard attacks the nests of social hymenopterans, eating wasp larvae; it is the only known predator of the dangerous Asian giant hornet or "yak-killer" ( Vespa mandarinia ). Likewise, roadrunners are
7625-500: The body fluids of their prey. Although vespid mandibles are adapted for chewing and they appear to be feeding on the organism, they are often merely macerating it into submission. The impact of the predation of wasps on economic pests is difficult to establish. The roughly 140 species of beewolf ( Philanthinae ) hunt bees, including honeybees, to provision their nests; the adults feed on nectar and pollen. With their powerful stings and conspicuous warning coloration , social wasps are
SECTION 60
#17328376201277750-572: The ceilings of the underground nests, acting as food storage for the rest of the colony. Not all social insects have distinct morphological differences between castes. For example, in the Neotropical social wasp Synoeca surinama , caste ranks are determined by social displays in the developing brood. These castes are sometimes further specialized in their behavior based on age, as in Scaptotrigona postica workers. Between approximately 0–40 days old,
7875-419: The clade Aculeata can sting their prey. The most commonly known wasps, such as yellowjackets and hornets , are in the family Vespidae and are eusocial , living together in a nest with an egg-laying queen and non-reproducing workers. Eusociality is favoured by the unusual haplodiploid system of sex determination in Hymenoptera, as it makes sisters exceptionally closely related to each other. However,
8000-421: The colony against predators, kleptoparasites , and competitors. In these groups, eusociality is produced by both high relatedness and by living in a restricted, shared area. Eusociality has evolved in three different lineages in the colonial crustacean genus Synalphaeus . S. regalis , S. microneptunus , S. filidigitus , S. elizabethae , S. chacei , S. riosi , S. duffyi , and S. cayoneptunus are
8125-523: The colony, it is protected by a specialized caste of sterile soldier trematodes. Soldiers are smaller, more mobile, and develop along a different pathway than sexually mature reproductives. One difference is that a soldier's mouthparts (pharynx) is five times as big as those of the reproductives. They make up nearly a quarter of the volume of the soldier. These soldiers do not have a germinal mass, never metamorphose to be reproductive, and are, therefore, obligately sterile. Soldiers are readily distinguished from
8250-432: The cooperative behavior of the bees, males and females alike, as they took responsibility for at least one duty (i.e., burrowing, cell construction, oviposition ) within the colony. The cooperativeness was essential as the activity of one labor division greatly influenced the activity of another. Eusocial colonies can be viewed as superorganisms , with individual castes being analogous to different tissue or cell types in
8375-422: The cost of investing in non-reproductive offspring, and an increased risk of disease. All reversals to solitarity have occurred among primitively eusocial groups; none have followed the emergence of advanced eusociality. The "point of no return" hypothesis posits that the morphological differentiation of reproductive and non-reproductive castes prevents highly eusocial species such as the honeybee from reverting to
8500-424: The cuckoo or jewel wasps ( Chrysididae ), are kleptoparasites, laying their eggs in the nests of other wasp species to exploit their parental care. Most such species attack hosts that provide provisions for their immature stages (such as paralyzed prey items), and they either consume the provisions intended for the host larva, or wait for the host to develop and then consume it before it reaches adulthood. An example of
8625-548: The developing wasp larvae. The largest social wasp is the Asian giant hornet , at up to 5 centimetres (2.0 in) in length. The various tarantula hawk wasps are of a similar size and can overpower a spider many times its own weight, and move it to its burrow, with a sting that is excruciatingly painful to humans. The solitary giant scoliid , Megascolia procer , with a wingspan of 11.5 cm, has subspecies in Sumatra and Java ; it
8750-680: The dwarf mongoose, the breeding pair receives food priority and protection from subordinates and rarely has to defend against predators. Scientists have debated whether humans are prosocial or eusocial. Edward O. Wilson called humans eusocial apes, arguing for similarities to ants, and observing that early hominins cooperated to rear their children while other members of the same group hunted and foraged. Wilson and others argued that through cooperation and teamwork, ants and humans form superorganisms. Wilson's claims were vigorously rejected by critics of group selection theory, which grounded Wilson's argument, and because human reproductive labor
8875-438: The early phase of infection. This strategic positioning allows them to effectively defend against invaders, similar to how soldier distribution patterns are seen in other animals with defensive castes. They "appear to be an obligately sterile physical caste, akin to that of the most advanced social insects". Among mammals, two species in the rodent group Phiomorpha are eusocial, the naked mole-rat ( Heterocephalus glaber ) and
9000-509: The eight recorded species of parasitic shrimp that rely on fortress defense and live in groups of closely related individuals in tropical reefs and sponges. They live eusocially with a single breeding female, and a large number of male defenders armed with enlarged snapping claws. There is a single shared living space for the colony members, and the non-breeding members act to defend it. The fortress defense hypothesis additionally points out that because sponges provide both food and shelter, there
9125-476: The eponymous chorus of old men in Aristophanes ' 422 BC comedy The Wasps , and in science fiction from H. G. Wells 's 1904 novel The Food of the Gods and How It Came to Earth , featuring giant wasps with three-inch-long stings. The name 'Wasp' has been used for many warships and other military equipment. The wasps are a cosmopolitan paraphyletic grouping of hundreds of thousands of species, consisting of
9250-524: The eusocial phenotype, with one queen supported by sterile workers and sexually active males ( drones ). In queenless colonies, the lack of queen pheromones causes winged females to quickly shed their wings, develop ovaries and lay eggs. These virgin replacement queens assume the role of the queen and start to produce queen pheromones. Similarly, queen weaver ants Oecophylla longinoda have exocrine glands that produce pheromones which prevent workers from laying reproductive eggs. Similar mechanisms exist in
9375-722: The evolution of eusociality is supported by evidence such as experimentally induced reproductive division of labor, for example when normally solitary queens are forced together. Conversely, female Damaraland mole-rats undergo hormonal changes that promote dispersal after periods of high rainfall. Climate too appears to be a selective agent driving social complexity; across bee lineages and Hymenoptera in general, higher forms of sociality are more likely to occur in tropical than temperate environments. Similarly, social transitions within halictid bees , where eusociality has been gained and lost multiple times, are correlated with periods of climatic warming. Social behavior in facultative social bees
9500-437: The evolution of eusociality, monogamy should be the ancestral state, because it maximizes the relatedness of colony members. Increased parasitism and predation rates are the primary ecological drivers of social organization. Group living affords colony members defense against enemies, specifically predators, parasites, and competitors, and allows them to gain advantage from superior foraging methods. The importance of ecology in
9625-464: The families Vespidae , Crabronidae , Sphecidae , and Pompilidae , attack and sting prey items that they use as food for their larvae; while Vespidae usually macerate their prey and feed the resulting bits directly to their brood, most predatory wasps paralyze their prey and lay eggs directly upon the bodies, and the wasp larvae consume them. Apart from collecting prey items to provision their young, many wasps are also opportunistic feeders, and will suck
9750-512: The family Vespidae contains social species, primarily in the subfamilies Vespinae and Polistinae . With their powerful stings and conspicuous warning coloration , often in black and yellow, social wasps are frequent models for Batesian mimicry by non-stinging insects, and are themselves involved in mutually beneficial Müllerian mimicry of other distasteful insects including bees and other wasps. All species of social wasps construct their nests using some form of plant fiber (mostly wood pulp) as
9875-579: The first species to be used was Encarsia formosa , a parasitoid of a range of species of whitefly . It entered commercial use in the 1920s in Europe, was overtaken by chemical pesticides in the 1940s, and again received interest from the 1970s. Encarsia is being tested in greenhouses to control whitefly pests of tomato and cucumber , and to a lesser extent of aubergine (eggplant), flowers such as marigold , and strawberry . Several species of parasitic wasp are natural predators of aphids and can help to control them. For instance, Aphidius matricariae
10000-513: The fossil record in the Jurassic , and diversified into many surviving superfamilies by the Cretaceous . They are a successful and diverse group of insects with tens of thousands of described species; wasps have spread to all parts of the world except for the polar regions. The largest social wasp is the Asian giant hornet , at up to 5 centimetres (2.0 in) in length; among the largest solitary wasps
10125-406: The ground. Mud daubers and pollen wasps construct mud cells in sheltered places. Potter wasps similarly build vase-like nests from mud, often with multiple cells, attached to the twigs of trees or against walls. Predatory wasp species normally subdue their prey by stinging it, and then either lay their eggs on it, leaving it in place, or carry it back to their nest where an egg may be laid on
10250-449: The habitat, and use more of the available resources than non-eusocial species. The trematodes are a class of parasitic flatworm, also known as flukes. One species, Haplorchis pumilio , has evolved eusociality involving a colony creating a class of sterile soldiers. One fluke invades a host and establishes a colony of dozens to thousands of clones that work together to take it over. Since rival trematode species can invade and replace
10375-429: The hormonally based behavioral development of workers and suppress their ovarian development. Both behavioral effects mediated by the nervous system often leading to recognition of queens ( releaser ) and physiological effects on the reproductive and endocrine system ( primer ) are attributed to the same pheromones. These pheromones volatilize or are deactivated within thirty minutes, allowing workers to respond rapidly to
10500-416: The immature and mature reproductive worms. Soldiers are more aggressive than reproductives, attacking heterospecific trematodes that infect their host in vitro . H. pumilio soldiers do not attack conspecifics from other colonies. The soldiers are not evenly distributed throughout the host body. They are found in the highest numbers in the basal visceral mass, where competing trematodes tend to multiply during
10625-553: The individuals cooperatively care for the brood of a single reproductive female (the queen) to which they are most likely related. Thus, it is uncertain whether mole rats are truly eusocial, since their social behavior depends largely on their resources and environment. Some mammals in the Carnivora and Primates have eusocial tendencies, especially meerkats ( Suricata suricatta ) and dwarf mongooses ( Helogale parvula ). These show cooperative breeding and marked reproductive skews. In
10750-399: The individuals in the colony are to some degree specialized for tasks, a division of labor . Eusociality is a rare but widespread phenomenon in species in at least seven orders in the animal kingdom , as shown in the phylogenetic tree (non-eusocial groups not shown). All species of termites are eusocial, and it is believed that they were the first eusocial animals to evolve, sometime in
10875-592: The insects among the Hexapoda , six-legged animals with segmented bodies; their closest relatives are the Diplura (bristletails). Collembola (springtails) [REDACTED] Protura (coneheads) [REDACTED] Diplura (two-pronged bristletails) [REDACTED] Insecta (=Ectognatha) [REDACTED] The internal phylogeny is based on the works of Wipfler et al. 2019 for the Polyneoptera , Johnson et al. 2018 for
11000-417: The largest group of eusocial insects, including ants , bees , and wasps —divided into castes: reproductive queens , drones , more or less sterile workers, and sometimes also soldiers that perform specialized tasks. In the well-studied social wasp Polistes versicolor , dominant females perform tasks such as building new cells and ovipositing, while subordinate females tend to perform tasks like feeding
11125-561: The larvae and foraging. The task differentiation between castes can be seen in the fact that subordinates complete 81.4% of the total foraging activity, while dominants only complete 18.6% of the total foraging. Eusocial species with a sterile caste are sometimes called hypersocial. While only a moderate percentage of species in bees (families Apidae and Halictidae ) and wasps ( Crabronidae and Vespidae ) are eusocial, nearly all species of ants ( Formicidae ) are eusocial. Some major lineages of wasps are mostly or entirely eusocial, including
11250-465: The larvae exude copious amounts of salivary secretions that are avidly consumed by the adults. These include both sugars and amino acids , and may provide essential protein-building nutrients that are otherwise unavailable to the adults (who cannot digest proteins). In wasps, as in other Hymenoptera, sex is determined by a haplodiploid system, which means that females are unusually closely related to their sisters, enabling kin selection to favour
11375-406: The legs or other parts of the body. Their sense of smell is via receptors, usually on the antennae and the mouthparts. Nearly all insects hatch from eggs . Insect growth is constrained by the inelastic exoskeleton, so development involves a series of molts . The immature stages often differ from the adults in structure, habit and habitat. Groups that undergo four-stage metamorphosis often have
11500-561: The loss of their queen. The levels of two of the aliphatic compounds increase rapidly in virgin queens within the first week after emergence from the pupa , consistent with their roles as sex attractants during the mating flight. Once a queen is mated and begins laying eggs, she starts producing the full blend of compounds. In several ant species, reproductive activity is associated with pheromone production by queens. Mated egg-laying queens are attractive to workers, whereas young winged virgin queens elicit little or no response. Among ants,
11625-610: The majority of social bee diversity, have their lowest diversity in the tropics, being largely limited to temperate regions. Once pre-adaptations such as group formation, nest building, high cost of dispersal, and morphological variation are present, between-group competition has been suggested as a driver of the transition to advanced eusociality. M. A. Nowak, C. E. Tarnita, and E. O. Wilson proposed in 2010 that since eusociality produces an extremely altruistic society, eusocial groups should out-reproduce their less cooperative competitors, eventually eliminating all non-eusocial groups from
11750-506: The majority of wasp species are solitary, with each adult female living and breeding independently. Females typically have an ovipositor for laying eggs in or near a food source for the larvae, though in the Aculeata the ovipositor is often modified instead into a sting used for defense or prey capture. Wasps play many ecological roles . Some are predators or pollinators , whether to feed themselves or to provision their nests. Many, notably
11875-529: The models for many species of mimic. Two common cases are Batesian mimicry , where the mimic is harmless and is essentially bluffing, and Müllerian mimicry , where the mimic is also distasteful, and the mimicry can be considered mutual. Batesian mimics of wasps include many species of hoverfly and the wasp beetle . Many species of wasp are involved in Müllerian mimicry, as are many species of bee . While wasp stings deter many potential predators, bee-eaters (in
12000-402: The name "bugs" for a narrow category of " true bugs ", insects of the order Hemiptera , such as cicadas and shield bugs . Other terrestrial arthropods, such as centipedes , millipedes , woodlice , spiders , mites and scorpions , are sometimes confused with insects, since they have a jointed exoskeleton. Adult insects are the only arthropods that ever have wings, with up to two pairs on
12125-454: The narrow-waisted clade Apocrita without the ants and bees . The Hymenoptera also contain the somewhat wasplike but unwaisted Symphyta , the sawflies. The term wasp is sometimes used more narrowly for members of the Vespidae , which includes several eusocial wasp lineages, such as yellowjackets (the genera Vespula and Dolichovespula ), hornets (genus Vespa ), and members of
12250-469: The nineteenth-century evolution debate. The Ichneumonidae contributed to Charles Darwin 's doubts about the nature and existence of a well-meaning and all-powerful Creator. In an 1860 letter to the American naturalist Asa Gray , Darwin wrote: I own that I cannot see as plainly as others do, and as I should wish to do, evidence of design and beneficence on all sides of us. There seems to me too much misery in
12375-554: The only invertebrates that can achieve sustained powered flight; insect flight evolved just once. Many insects are at least partly aquatic , and have larvae with gills; in some species, the adults too are aquatic. Some species, such as water striders , can walk on the surface of water. Insects are mostly solitary, but some, such as bees , ants and termites , are social and live in large, well-organized colonies . Others, such as earwigs , provide maternal care, guarding their eggs and young. Insects can communicate with each other in
12500-428: The only real predators of tarantula hawk wasps . Social wasps are considered pests when they become excessively common, or nest close to buildings. People are most often stung in late summer and early autumn, when wasp colonies stop breeding new workers; the existing workers search for sugary foods and are more likely to come into contact with humans. Wasp nests made in or near houses, such as in roof spaces, can present
12625-401: The opportunity. One plant, the epiphytic staghorn fern, Platycerium bifurcatum ( Polypodiaceae ), may exhibit a primitive form of eusocial behavior amongst clones. The evidence for this is that individuals live in colonies, where they are structured in different ways, with fronds of differing size and shape, to collect and store water and nutrients for the colony to use. At the top of
12750-403: The other female's egg from the prey and laying their own in its place. According to Emery's rule , social parasites , especially among insects, tend to parasitise species or genera to which they are closely related. For example, the social wasp Dolichovespula adulterina parasitises other members of its genus such as D. norwegica and D. arenaria . Many wasp lineages, including those in
12875-563: The outside of the host. The host remains alive until the parasitoid larvae pupate or emerge as adults. The Ichneumonidae are specialized parasitoids, often of Lepidoptera larvae deeply buried in plant tissues, which may be woody . For this purpose, they have exceptionally long ovipositors; they detect their hosts by smell and vibration. Some of the largest species, including Rhyssa persuasoria and Megarhyssa macrurus , parasitise horntails , large sawflies whose adult females also have impressively long ovipositors. Some parasitic species have
13000-430: The prey item and the nest sealed, or several smaller prey items may be deposited to feed a single developing larva. Apart from providing food for their offspring, no further maternal care is given. Members of the family Chrysididae , the cuckoo wasps, are kleptoparasites and lay their eggs in the nests of unrelated host species. Like all insects, wasps have a hard exoskeleton which protects their three main body parts,
13125-569: The primary material, though this can be supplemented with mud, plant secretions (e.g., resin ), and secretions from the wasps themselves; multiple fibrous brood cells are constructed, arranged in a honeycombed pattern, and often surrounded by a larger protective envelope. Wood fibres are gathered from weathered wood, softened by chewing and mixing with saliva . The placement of nests varies from group to group; yellow jackets such as Dolichovespula media and D. sylvestris prefer to nest in trees and shrubs; Protopolybia exigua attaches its nests on
13250-627: The queen pheromone system of the fire ant Solenopsis invicta includes both releaser and primer pheromones. A queen recognition (releaser) pheromone is stored in the poison sac along with three other compounds. These compounds elicit a behavioral response from workers. Several primer effects have also been demonstrated. Pheromones initiate reproductive development in new winged females, called female sexuals. These chemicals inhibit workers from rearing male and female sexuals, suppress egg production in other queens of multiple queen colonies, and cause workers to execute excess queens. These pheromones maintain
13375-535: The reproduction of many flowering plants and so to their ecosystems. Many insects are ecologically beneficial as predators of pest insects, while a few provide direct economic benefit. Two species in particular are economically important and were domesticated many centuries ago: silkworms for silk and honey bees for honey . Insects are consumed as food in 80% of the world's nations, by people in roughly 3000 ethnic groups. Human activities are having serious effects on insect biodiversity . The word insect comes from
13500-415: The reproductive cycle depends on latitude ; Polistes erythrocephalus , for example, has a much longer (up to 3 months longer) cycle in temperate regions. The vast majority of wasp species are solitary insects. Having mated, the adult female forages alone and if it builds a nest, does so for the benefit of its own offspring. Some solitary wasps nest in small groups alongside others of their species, but each
13625-626: The reproductive output of other individuals that share their genes, especially their close relatives. Natural selection favors individuals to help their relatives when the cost of helping is less than the benefit gained by their relative multiplied by the fraction of genes that they share, i.e. when Cost < relatedness * Benefit . W. D. Hamilton suggested in 1964 that eusociality could evolve more easily among haplodiploid species such as Hymenoptera, because of their unusual relatedness structure. In haplodiploid species, females develop from fertilized eggs and males develop from unfertilized eggs. Because
13750-535: The roles of the sole reproducers, while soldiers and workers work together to create and maintain a living situation favorable for the brood. Queens produce multiple queen pheromones to create and maintain the eusocial state in their colonies; they may also eat eggs laid by other females or exert dominance by fighting. There are two eusocial rodents : the naked mole-rat and the Damaraland mole-rat . Some shrimps , such as Synalpheus regalis , are eusocial. E. O. Wilson and others have claimed that humans have evolved
13875-429: The sex of their offspring. Experimental infection of Muscidifurax uniraptor with the bacterium Wolbachia induced thelytokous reproduction and an inability to produce fertile, viable male offspring. Females of the solitary wasp parasitoid Venturia canescens can avoid mating with their brothers through kin recognition . In experimental comparisons, the probability that a female will mate with an unrelated male
14000-574: The solitary state. Pheromones play an important role in the physiological mechanisms of eusociality. Enzymes involved in the production and perception of pheromones were important for the emergence of eusociality within both termites and hymenopterans. The best-studied queen pheromone system in social insects is that of the honey bee Apis mellifera . Queen mandibular glands produce a mixture of five compounds, three aliphatic and two aromatic , which control workers. Mandibular gland extracts inhibit workers from constructing queen cells, which can delay
14125-402: The subfamilies Polistinae and Vespinae . The corbiculate bees (subfamily Apinae of family Apidae ) contain four tribes of varying degrees of sociality: the highly eusocial Apini (honey bees) and Meliponini (stingless bees), primitively eusocial Bombini (bumble bees), and the mostly solitary or weakly social Euglossini (orchid bees). Eusociality in these families is sometimes managed by
14250-582: The subfamily Polistinae . Hymenoptera in the form of Symphyta ( Xyelidae ) first appeared in the fossil record in the Lower Triassic . Apocrita, wasps in the broad sense, appeared in the Jurassic , and had diversified into many of the extant superfamilies by the Cretaceous ; they appear to have evolved from the Symphyta. Fig wasps with modern anatomical features first appeared in the Lower Cretaceous of
14375-449: The thing, he found it was twenty-seven and a half inches across its open wings, and its sting was three inches long. ... The day after, a cyclist riding, feet up, down the hill between Sevenoaks and Tonbridge, very narrowly missed running over a second of these giants that was crawling across the roadway. Wasp (1957) is a science fiction book by the English writer Eric Frank Russell ; it
14500-527: The thorax. Whether winged or not, adult insects can be distinguished by their three-part body plan, with head, thorax, and abdomen; they have three pairs of legs on the thorax. Estimates of the total number of insect species vary considerably, suggesting that there are perhaps some 5.5 million insect species in existence, of which about one million have been described and named. These constitute around half of all eukaryote species, including animals , plants , and fungi . The most diverse insect orders are
14625-518: The total of around 22,500 species is probably within 5% of the actual number there; they comment that Canada's list of 30,000 described species is surely over half of the actual total. They add that the 3000 species of the American Arctic must be broadly accurate. In contrast, a large majority of the insect species of the tropics and the southern hemisphere are probably undescribed. Some 30–40,000 species inhabit freshwater ; very few insects, perhaps
14750-420: The underside of leaves and branches; Polistes erythrocephalus chooses sites close to a water source. Other wasps, like Agelaia multipicta and Vespula germanica , like to nest in cavities that include holes in the ground, spaces under homes, wall cavities or in lofts. While most species of wasps have nests with multiple combs, some species, such as Apoica flavissima , only have one comb. The length of
14875-749: The upper Jurassic period (~150 million years ago). The other orders shown contain both eusocial and non-eusocial species, including many lineages where eusociality is inferred to be the ancestral state. Thus the number of independent evolutions of eusociality ( clades ) is not known. The major eusocial groups are shown in boldface in the phylogenetic tree. Mole-rats [REDACTED] Synalpheus spp. [REDACTED] [REDACTED] Kladothrips spp. [REDACTED] various Aphids [REDACTED] Austroplatypus incompertus [REDACTED] many Vespidae (wasps) [REDACTED] [REDACTED] many Bees [REDACTED] Staghorn fern Platycerium bifurcatum [REDACTED] Prior to
15000-399: The wasp larvae feed temporarily on their haemolymph , but if a parasitoid emerges from the host, the hyperparasites continue their life cycle inside the parasitoid. Parasitoids maintain their extreme diversity through narrow specialism. In Peru, 18 wasp species were found living on 14 fly species in only two species of Gurania climbing squash. Of the dozens of extant wasp families, only
15125-419: The workers perform tasks within the nest such as provisioning cell broods, colony cleaning, and nectar reception and dehydration. Once older than 40 days, S. postica workers move outside the nest for colony defense and foraging. In Lasioglossum aeneiventre , a halictid bee from Central America, nests may be headed by more than one female; such nests have more cells, and the number of active cells per female
15250-466: The world. I cannot persuade myself that a beneficent and omnipotent God would have designedly created the Ichneumonidae with the express intention of their feeding within the living bodies of caterpillars, or that a cat should play with mice. With its powerful sting and familiar appearance, the wasp has given its name to many ships, aircraft and military vehicles. Nine ships and one shore establishment of
15375-500: Was about twice as high as the chance of her mating with brothers. Female wasps appear to recognize siblings on the basis of a chemical signature carried or emitted by males. Sibling-mating avoidance reduces inbreeding depression that is largely due to the expression of homozygous deleterious recessive mutations. While the vast majority of wasps play no role in pollination, a few species can effectively transport pollen and pollinate several plant species. Since wasps generally do not have
15500-422: Was followed by at least one reversal to solitarity, giving a total of at least nine reversals. In a few species, solitary and eusocial colonies appear simultaneously in the same population, and different populations of the same species may be fully solitary or eusocial. This suggests that eusociality is costly to maintain, and can only persist when ecological variables favor it. Disadvantages of eusociality include
15625-511: Was then discovered in a group of chordates , the mole-rats. Further research distinguished another possibly important criterion for eusociality, "the point of no return". This is characterized by having individuals fixed into one behavioral group, usually before reproductive maturity. This prevents them from transitioning between behavioral groups, and creates a society with individuals truly dependent on each other for survival and reproductive success. For many insects, this irreversibility has changed
#126873