|Polistes annularis at a mature nest|
Polistes annularis (P. annularis) is a species of paper wasp which lives throughout the Caribbean and in parts of North America. Its species name is Latin for "ringed" and it is known for its distinct red body color. It builds its nest under overhangs near bodies of water that minimize the amount of sunlight penetration.It clusters its nests together in large aggregations, and consumes nectar and other insects. Its principal predator is the ant, although birds are also known to prey on it. It is a primitively eusocial wasp, meaning that all individuals develop the capacity for reproduction, regardless of social caste. This primitive eusociality has been seen in bees as well, including the sweat bee, Lasioglossum zephyrum . As such, P. annularis demonstrates behavior typical of other polistine wasps, and has a dominance hierarchy, relatively small colony size, and a female-biased sex ratio. Unlike other wasps, P. annularis is relatively robust in winter conditions, and has also been observed to store honey in advance of hibernation. It is closely related to P. major, P. buysonni, and others in the subgenus Aphanilopterus, and slightly less related to the more common P. bellicosus, P. carolina, P. metricus, and P. fuscatus .
In biology, a species ( ) is the basic unit of classification and a taxonomic rank of an organism, as well as a unit of biodiversity. A species is often defined as the largest group of organisms in which any two individuals of the appropriate sexes or mating types can produce fertile offspring, typically by sexual reproduction. Other ways of defining species include their karyotype, DNA sequence, morphology, behaviour or ecological niche. In addition, paleontologists use the concept of the chronospecies since fossil reproduction cannot be examined. While these definitions may seem adequate, when looked at more closely they represent problematic species concepts. For example, the boundaries between closely related species become unclear with hybridisation, in a species complex of hundreds of similar microspecies, and in a ring species. Also, among organisms that reproduce only asexually, the concept of a reproductive species breaks down, and each clone is potentially a microspecies.
Paper wasps are vespid wasps that gather fibers from dead wood and plant stems, which they mix with saliva, and use to construct water-resistant nests made of gray or brown papery material. Some types of paper wasps are also sometimes called umbrella wasps, due to the distinctive design of their nests.
North America is a continent entirely within the Northern Hemisphere and almost all within the Western Hemisphere; it is also considered by some to be a northern subcontinent of the Americas. It is bordered to the north by the Arctic Ocean, to the east by the Atlantic Ocean, to the west and south by the Pacific Ocean, and to the southeast by South America and the Caribbean Sea.
While many other North American Polistes species show sexual dimorphism in coloration, P. annularis and P. erythrocephalus do not. 18.5–23.5 mm (0.73–0.93 in) long in females, and 17.5–19.5 mm (0.69–0.77 in) long in males. Both males and females are red-faced, which makes intersex determination less straightforward; however, it also makes it easier to recognize members of this species compared to other closely related species. Its initial metasomal segment is narrow, a feature that it has in common with P. bahamensis.This species differs from P. metricus in terms of the coloration of the antennae and thorax. There is geographical variation in coloration between northern and southern populations. In the north, the thorax of P. annularis has ferruginous (rust-red) markings on a predominantly black background, while in the south, the thorax is mostly ferruginous, with black markings. The legs also vary from black to ferruginous. In terms of size, the fore wings are
Sexual dimorphism is the condition where the two sexes of the same species exhibit different characteristics beyond the differences in their sexual organs. The condition occurs in many animals and some plants. Differences may include secondary sex characteristics, size, weight, color, markings, and may also include behavioral and cognitive differences. These differences may be subtle or exaggerated, and may be subjected to sexual selection. The opposite of dimorphism is monomorphism.
Polistes erythrocephalus is a species of paper wasp in the subfamily Polistinae of family Vespidae found in Central and South America. P. erythrocephalus is a eusocial wasp, meaning that it possesses both reproductive and non-reproductive castes. The cooperation between the two castes to raise young demonstrates the altruistic nature of these wasps. P. erythrocephalus exhibits a four-stage colony cycle, as do many other Polistes wasps. This species generally feeds on larvae, occasionally their own, and is preyed upon by species such as army ants.
Antennae, sometimes referred to as "feelers", are paired appendages used for sensing in arthropods.
P. annularis is very similar in appearance to P. bahamensis. To distinguish P. annularis from P. bahamensis, one should notice that P.annularis has no yellow mark on its mesopleuron and usually also has no yellow apical tergum band. In addition, its mesosomal yellow markings show less development.Within the P. annularis species, reproductives and foundresses can be readily distinguished, as well. Reproductive females can be recognized visually because their wings are unworn, since they do not forage much (unlike the workers). In their abdominal cavities, large amounts of white-colored fat are stored beneath the intersegmental membrane. Foundresses can be discriminated from workers on the basis of their differential behaviors. Nests can be identified by their paper material and the way their cells are openly exposed to the external environment. P. annularis is also classified as a primitively eusocial wasp, which means that all individuals develop the capacity to reproduce over their lifetimes, whether or not they actually do so.
The mesothorax is the middle of the three segments in the thorax of an insect, and bears the second pair of legs. Its principal sclerites are the mesonotum (dorsal), the mesosternum (ventral), and the mesopleuron (lateral) on each side. The mesothorax is the segment that bears the forewings in all winged insects, though sometimes these may be reduced or modified, as in beetles (Coleoptera) or Dermaptera, in which they are sclerotized to form the elytra, and the Strepsiptera, in which they are reduced to form halteres. All adult insects possess legs on the mesothorax. In some groups of insects, the mesonotum is hypertrophied, such as in Diptera, Hymenoptera, and Lepidoptera), in which the anterior portion of the mesonotum forms most of the dorsal surface of the thorax. In these orders, there is also typically a small sclerite attached to the mesonotum that covers the wing base, called the tegula. In one group of insects, the Hemiptera, the dorsal surface of the thorax is typically formed primarily of the prothorax, but also in part by the enlarged posterior portion of the mesonotum, called the scutellum; in the Coleoptera, the scutellum may or may not be visible, usually as a small triangular plate between the elytral bases, thus similar in position to the Hemipteran scutellum. In Diptera and Hymenoptera the mesothoracic scutellum is also distinct, but much smaller than the mesoscutum.
A tergum is the dorsal ('upper') portion of an arthropod segment other than the head. The anterior edge is called the base and posterior edge is called the apex or margin. A given tergum may be divided into hardened plates or sclerites commonly referred to as tergites. For a detailed explanation of the terminology, see Kinorhynchs have tergal and sternal plates too, though seemingly not homologous with those of arthropods.
The mesosoma is the middle part of the body, or tagma, of arthropods whose body is composed of three parts, the other two being the prosoma and the metasoma. It bears the legs, and, in the case of winged insects, the wings.
The mandible is the insect organ for biting and crushing, analogous to the jaw in mammals. In the genus Polistes , the lateral mandibular groove is smaller in size than in other genera of social wasps. A common misconception is that the mandibular gland is the anatomical portion shaped like a sac. In actuality, the sac formation is the gland reservoir that feeds into the gland itself. The actual gland is pressed up against the sac surface. Gland cells are shaped like polygons. Like poisonous structures in formicine ants, gland cells are continuous with the gland reservoir, but no filaments extend from the gland or sac as they do in the ants. The sac is closest to mandible’s medial portion. A duct exits the sac. The duct opening is encircled by a sphincter muscle controlling the gland’s secretions. The duct is opened by sclerotized bars in conjunction with the hypopharynx. When the hypopharynx moves, pressure forms on the opening of the duct via the bars. When the bars dissipate this pressure, the duct closes.
The paired submandibular glands are major salivary glands located beneath the floor of the mouth. They each weigh about 15 grams and contribute some 60–67% of unstimulated saliva secretion; on stimulation their contribution decreases in proportion as the parotid secretion rises to 50%.
In elementary geometry, a polygon is a plane figure that is described by a finite number of straight line segments connected to form a closed polygonal chain or polygonal circuit. The solid plane region, the bounding circuit, or the two together, may be called a polygon.
The Formicinae are a subfamily within the Formicidae containing ants of moderate evolutionary development.
The nest pedicel, which is the stalk by which the entire nest hangs from the horizontal face of the overhang, is made from a durable material composed of the wasps’ oral secretion. It has a nitrogen content of 11% and is mainly carbohydrates and proteins. Pedicel proteins are rich in glycine, proline, alanine, and serine. These amino acids are also found in the silks of other insects. Another minor component is N-acetylglucosamine, which is probably bound to the pedicel protein. Proline is a major component of structural proteins and likely contributes to the structural strength of the pedicel in holding up the rest of the nest. The pedicel suspends the nest high in the air and precludes many predators from getting close to the nest.However, birds often try to knock nests off the cliff, and colonies that hang low toward the ground can be attacked and eaten by raccoons. Cellulose makes up most of the nest paper. Larval silk is a protein with high amounts of serine and alanine. When larvae mature, silk is produced in their labial glands. Larvae spin cocoons that enclose themselves into their cell in the nest.
A carbohydrate is a biomolecule consisting of carbon (C), hydrogen (H) and oxygen (O) atoms, usually with a hydrogen–oxygen atom ratio of 2:1 (as in water) and thus with the empirical formula Cm(H2O)n (where m may be different from n). This formula holds true for monosaccharides. Some exceptions exist; for example, deoxyribose, a sugar component of DNA, has the empirical formula C5H10O4. The carbohydrates are technically hydrates of carbon; structurally it is more accurate to view them as aldoses and ketoses.
Proteins are large biomolecules, or macromolecules, consisting of one or more long chains of amino acid residues. Proteins perform a vast array of functions within organisms, including catalysing metabolic reactions, DNA replication, responding to stimuli, providing structure to cells and organisms, and transporting molecules from one location to another. Proteins differ from one another primarily in their sequence of amino acids, which is dictated by the nucleotide sequence of their genes, and which usually results in protein folding into a specific three-dimensional structure that determines its activity.
Glycine (symbol Gly or G; ) is an amino acid that has a single hydrogen atom as its side chain. It is the simplest amino acid, with the chemical formula NH2‐CH2‐COOH. Glycine is one of the proteinogenic amino acids. It is encoded by all the codons starting with GG (GGU, GGC, GGA, GGG). Glycine is also known as a "helix breaker", due to its ability to act as a hinge in the secondary structure of proteins.
Members of P. annularis have cuticular hydrocarbons on the surface of their bodies that may serve as social recognition factors. These are composed of a complex mixture containing dimethylalkanes, n-alkanes, and monomethylalkanes. They are straight-chain and have methyl branches. The most common chemicals are 13,17- dimethylhentriacontane (18%) 3-methyl-nonacosane (13%), 3-methylheptacosane (11%), and n-heptacosane (8%). These serve to protect the wasps from dehydration. Their composition tends to be unique to each species of wasp. Hydrocarbons are present on the surface of workers, males, eggs, and larvae, as well as the surface of the nest and its pedicel. The lipids in the nest paper probably function in kin recognition among workers, while those in the pedicel likely deter predators. The free fatty acids of the pedicel induce the necrophoric response in ants, which causes them to avoid the pedicel rather than cross over it and prey on the nest’s inhabitants. In ants, the necrophoric response is defined as the behavior of recognizing dead colony members and carrying them to a refuse pile away from the nest. Adult males have the hydrocarbon compounds as the workers, but they are present in different amounts. In males, the most common component is 3-methylnonacosane (21%); in eggs, 3-methylnonacosane makes up 23% of lipids; in larvae 13- and 15-methylnonacosane are the most common (15%). Nest paper and pedicel have much larger hydrocarbon units, between 27 and 31 carbons in length. The pedicel also contains hexadecanoic acid and octadecanoic acid.
A cuticle, or cuticula, is any of a variety of tough but flexible, non-mineral outer coverings of an organism, or parts of an organism, that provide protection. Various types of "cuticle" are non-homologous, differing in their origin, structure, function, and chemical composition.
In organic chemistry, a hydrocarbon is an organic compound consisting entirely of hydrogen and carbon. Hydrocarbons are examples of group 14 hydrides. Hydrocarbons from which one hydrogen atom has been removed are functional groups called hydrocarbyls. Because carbon has 4 electrons in its outermost shell carbon has exactly four bonds to make, and is only stable if all 4 of these bonds are used.
In chemistry, an open-chain compound or acyclic compound is a compound with a linear structure, rather than a cyclic one. An open-chain compound having no side chains is called a straight-chain compound. Many of the simple molecules of organic chemistry, such as the alkanes and alkenes, have both linear and ring isomers, that is, both acyclic and cyclic, with the latter often classified as aromatic. For those with 4 or more carbons, the linear forms can have straight-chain or branched-chain isomers. The lowercase prefix n- denotes the straight-chain isomer; for example, n-butane is straight-chain butane, whereas i-butane is isobutane. Cycloalkanes are isomers of alkenes, not of alkanes, because the ring's closure involves a C=C bond. Having no rings, all open-chain compounds are aliphatic.
P. annularis has been used as a model species to investigate the power of microsatellite markers in maternity assignment of social insects. Historically, maternity assignment has been problematic in social insects for several reasons: 1) Possible mothers are usually related so their offspring are highly genetically similar. 2) The real mothers may already have died, increasing the risk of assigning offspring to the wrong surviving mothers. 3) The father’s genome is inaccessible because males mate and die before their offspring are even born. Microsatellite markers have been demonstrated to nullify these problems in P. annularis. They are single-locus, codominant markers that vary dramatically for number of simple sequence repeats. They can be readily amplified using the polymerase chain reaction, and the samples of DNA can be minuscule. This allows scientists to access the genotypes of very young embryos and even sperm from spermathecae. Through the genotypes of stored sperm, alleles of dead fathers are recovered. They can then combine these data with the maternal genotype to improve the accuracy of the maternity assignment.
The first description of P. annularis was published by Carl Linnaeus in his 1763 Centuria Insectorum , where he named the species Vespa annularis.It was moved to the genus Polistes by Johan Christian Fabricius in 1804, two years after Pierre André Latreille had erected the new genus.
P. annularis is classified as part of the kingdom Animalia, the phylum Arthropoda, the subphylum Hexapoda, the class Insecta, the order Hymenoptera, the suborder Aculeata, the superfamily Vespoidea, and the family Vespidae. Its subphylum Hexapoda indicates it has six feet; the order Hymenoptera includes ants, bees, wasps, and sawflies; the Aculeata include ants, bees, and stinging wasps in particular; the Vespoidea include yellow jackets, hornets, paper wasps, potter wasps, mason wasps, and pollen wasps. The genus name Polistes is most likely derived from the Greek polistes (πολιστης) which is translated as “founder of a city”. The species name annularis is the Latin word that means “ringed”. A common name for P. annularis is the red paper wasp, due to its distinctive red coloration.
P. annularis is placed within the subfamily Polistinae (paper wasps), which is the second-largest of the subfamilies within the Vespidae. The Polistinae contain two main behavioral groups: wasps which form nests with large number of workers, and those wasps which found nests with few workers and foundresses (the latter including P. annularis). This subfamily likely arose in the mid- to late Jurassic period, around 145 to 175 million years ago. P. annularis diverged from P. bellicosus between 10 and 80 million years ago.It is currently placed in the New World subgenus Aphanilopterus.
P. annularis is found throughout the Caribbean and across the eastern United States from New York to Florida, west to a line from South Dakota to Texas.This range is similar to that of P. exclamans .
P. annularis forms its nests on the branches of trees and shrubs, as well as in sheltered parts of some buildings.However, it is also known to group its nests in large colonies called aggregations. These tend to be built on the underside of overhangs (rocky cliffs, for example) in close proximity to bodies of water. Ideally, the overhanging structure should block exposure to sunlight for most of the day. In the natural environment, P. annularis prefers cliffs by riversides. A limiting factor to nest building is the presence of a suitable overhang that minimizes sun exposure. The nests differ markedly from those of other species in the genus Polistes. They are much larger, with around 500 cells, and are wide, rather than the slender, elongated nests seen in some other species. P. annularis lives in nests made of paper that have cells exposed to the external environment. The word “cells” is used to describe the room-like excavations or depressions built by the foundresses and workers that house the wasps, their larvae, and their food stores.
In the springtime, mated females called foundresses join together in groups to start a new nest.They emerge from cracks within the rocky cliff wall where they have spent the winter in hibernation, and return to their natal nests from the previous fall season. They initiate construction of wholly new paper nests, normally only a few meters away from the natal nest of the foundresses, and the group of foundresses usually consists of females from the same natal nest. Groups of foundresses are termed “associations”, which vary in size, but they can vary from one (a sole foundress) to as many as 22 foundresses cooperating together to found a new colony (nest), with five females on average. Each of the foundresses has spermathecae that are fully loaded with sperm, since they have just mated the previous winter. Their ovaries are full of mature oocytes. Of all the foundresses in an association, only one foundress assumes the role of queen. This occurs promptly once the nest has been initiated, and at this time the foundresses establish a dominance hierarchy among themselves. The most dominant foundress becomes the queen. She lays the vast majority of eggs in comparison with the other foundresses. In the meantime, the other foundresses serve as foragers and nest-builders. They manage the nourishment and physical defense of the brood of larvae that are developing in the nest, until the larvae pupate and finally emerge from their pupae as the first generation of workers. At that point, the co-foundresses have finished their work of foraging, and remain on the nest from then on.
The first generation of offspring is composed mainly of female workers, but some males may be present. The appearance of males in the first brood varies from nest to nest. Only in subsequent generations (after the first generation of offspring) will some offspring develop as reproductives: females first, then males.Generally, several generations of female worker offspring emerge (hatch) from the nest over the course of the summer, and then reproductives start to be produced. Reproductives tend to emerge about one month before the nest is empty of developing brood. A few days after males emerge, they leave their natal nest. The probability of a given female developing as a worker or as a reproductive likely depends more on ambient conditions than on predetermined factors. Although the probability is very low, a worker herself can eventually mate and assume the role of queen in the event that all foundresses of the nest die or leave permanently. Between mid-July and mid-October, P. annularis nests arrest their brood production.
During the fall season, females prepare for winter by collecting nectar. This is stored in highly concentrated form in the cells of the nest. During the winter, P. annularis abandons its nest and resides in hibernacula, which are locations of shelter at which animals hibernate. On warmer days during the winter, females of P. annularis fly back to their nests to consume their stored nectar (which is now honey) and to interact with their nestmates. In early January, reproductive males and females commence mating at the hibernacula. In the following spring, foundresses are observed to retain association with their nestmates from the natal nest of the previous autumn.
P. annularis has been found to exhibit slight variations in its colony cycle from year to year based on environmental conditions, in part due to the ability of females to switch castes. Typically, the largest and top-ranking female founds a nest and lays the largest percentage of eggs, while subordinates forage. After workers emerge from the eggs, many of the subordinate foundresses disappear; the nest usually loses its original queen before more eggs can be laid at the end of the season. A worker with fully developed ovaries takes over the nest and becomes a gyne. Earlier queen death corresponds to an earlier arrest in rearing brood, which may be due to a decrease in relatedness between the new queen and the nascent females, or due to internal conflict on the nest. Additionally, if resources decrease, such as during a drought, brood rearing ends sooner than in more prosperous years, and females choose to become gynes as opposed to workers. Many of these variations can be rationalized via relatedness.
P. annularis queens have the tendency to outlive all of the subordinate cofoundresses of their associations. Over the course of the colony season, the number of mated workers with the ability to lay eggs increases, while queens’ dominance shows a trend of becoming stronger and more pronounced. In general, foundresses have greater inclusive fitness if they are associated with smaller colonies. Notably, lone foundresses (with no other foundresses in the association) tend to produce far more offspring than do the subordinate co-foundresses of other nests. The ability of a foundress to found a nest on her own is likely in correlation to the length of her wings (her body size), the mass of her dehydrated body, and the mass of her body fat. At nighttime and in the early morning, P. annularis’ entire female nest population is located on the nest.The moment that a foundress is established in the association of a new nest, she will from then on never leave that nest and join up with foundresses of a separate nest unless her proper nest is wrecked. In the event of a destroyed nest, a foundress may occasionally enter into the association of another nest’s foundresses who originally came from her same natal nest.
P. annularis, a eusocial animal, demonstrates a dominance hierarchy, due to group competition over scarce resources.Within a colony, certain wasps will chew on or attack others to demonstrate power. Individuals that are ranked differently demonstrate different behaviors; higher ranked wasps have a propensity for “tailwagging” and “checking cells” as compared to lower ranked workers, similar to Polistes dominula . Workers have been observed to forage for caterpillars more often than queens. Queens, the highest ranked individual in a nest, will usually lay the highest percentage of eggs, though subordinates are sometimes allowed to lay eggs as well. Should a foreign organism attempt to land, a female on the nest will engage the arriving wasp with her antennae. This clash may last for several minutes and may escalate into grappling. Queens are more active on larger and newer nests. Many of these behaviors are the result of high reproductive competition between females. Despite the hierarchy and its dependence on queen size, larger queens do not necessarily inhibit egg laying by subordinates better than smaller queens. However, queens do develop far larger and more developed ovaries than their subordinates, and often have more mature eggs within.
Much of P. annularis’s dominance hierarchy is dependent on dry weight, residue weight, wing length, and fat content. Females from different nests exhibit considerable variation in these factors, while females originating from the same nest are quite similar to each other in these factors. In some cases, the queen may be smaller than some of the worker wasps on the nest, weighing less and having a lower fat content, though this is atypical. Heavier wasps, as well as those with more fat content, typically have greater ovarian development; dry weight is typically more correlated with ovarian development than any other parameter.Ovarian development has been correlated with dominance hierarchy in other polistine wasps, Polistes gallicus and Polistes metricus .
Group nesting is especially prevalent and varied in P. annularis, with reports of foundresses per nest ranging from one to 28, with an arithmetic mean of 3.82 to 4.93, depending on the year. However, variation by year only explains 2% of the variance in the grouping size of foundresses. Only a small number of queens run a nest without a partner (about 5%), while about three-quarters of foundresses become subordinate to a queen on the nest. This species only become foundresses with other wasps if they were born in the same nest. Large aggregations of foundresses are seen when females reuse the nest in which they were born, either by reusing the cells themselves (uncommon) or by building a new nest on top of the old one.
Where females reuse the natal nest, between seven and eight foundresses typically may be seen on the nest, a significantly greater number than those seen on new nests (4.34).Foundress number plays a major role in determining the success of a colony. Colonies are on average 60 to 65% successful at producing workers and reproductives, respectively. However, nests with one foundress are only 20% successful at surviving until workers emerge. Nests with four or more foundresses have an 80% chance of success. Strangely, the inclusive fitness of subordinate foundresses is lower than their fitness in the case where they established a nest alone; it remains unclear why such subordinates do not leave the nest to establish their own. They may be “making the best of a bad job”, though evidence to indicate this is scant.
Multiple foundresses may create a nest; some studies have shown that four or five foundresses may inhabit a P. annularis nest.However, selective pressure tends to eliminate any additional foundresses once workers emerge. This is due to multiple factors. First, given the scarcity of space and resources, the foundresses compete with each other to raise the best offspring. In addition, workers can perform all the same functions as foundresses with minimal competition. Lastly, the relatedness between workers and their eggs versus those of the foundress - workers would be more related to their sisters than their own offspring. These factors may combine to result in the expulsion of the subordinate foundresses. Such behavior was first seen in another polistine wasp, P. gallicus. Subordinate foundress mortality has been found to significantly increase following worker emergence when compared to mortality rates prior to worker emergence. This pattern is also observed in P. exclamans and P. carolina , but not P. bellicosus. In some of these species, including P. annularis, subordinates decrease foraging rate following worker emergence.
Unlike other polistine wasps, P. annularis tends to more severe consequences after worker emergence, despite this change in behavior. This puzzle is currently unsolved, though it may deal with senescence. Decreased foraging also accompanies decreased aggression. Comparing across polistine wasps, foundress eviction is generally independent of rate of usurpation; P. annularis has a usurpation rate around 9%. When all foundresses are evicted, colony failure rate is high; in nests where multiple foundresses are evicted, around 19% of nests fail, but when only one foundress was originally present, almost 80% of nests fail. When pupae appear, queens are less aggressive towards their subordinates, as compared to the times at which only larvae are present.Some other social insects, such as ants, evict queens, while others, such as termites, seem to permit multiple queens.
In the absence of a queen, dominance conflicts arise between foundresses on the nest. Wasps routinely attack each other over a several-week period, and certain wasps eventually remit, leaving room for a new queen. Subordinates may then be chased from the nest. During the competitions, cell construction has been observed to stop, as well as oviposition.The new queen will lay more eggs than her cofoundresses, and dominate them as explained above. In so doing, she causes the ovaries of other workers to decrease in size, to the point that they will be eliminated following the hatching of new workers. The queen lays eggs, while the other females are constrained to laying eggs solely at the beginning of the association of the group. The queen may lay up to 55% of eggs, while her direct subordinates, named beta subordinates, lay most of the remaining eggs. Should the queen disappear, the previous beta subordinate takes over as the new queen, leading to increased aggression, which may result from the competition to lay eggs. When a foundress succeeds as the new queen, no additional aggression is observed, but if a worker becomes queen, aggression rises, likely because the dominance hierarchy is not as well established on these nests. Often when the queen dies, the oldest foundress succeeds her, due to her size and dominance in the nest. Despite aggression after the removal of a queen, brood care does not decrease.
Other species of Polistes exhibit a female-biased sex ratio due to the 3:1 relatedness between sisters, while still other members of the genus have a virtually unbiased sex ratio. Northern wasps tent to have biased ratios, while southern wasps are less biased, in large part because southern wasp sisters have lower relatedness. Since the relatedness between sisters in P. exclamans is 0.39, and since P. exclamans and P. annularis have similar geographic distributions, one may presume that the sex allocation patterns of P. annularis follow that of P. exclamans.
Members of the brood are highly related to the queen, but are less related to the subordinates and their mates, aligning more with a 1:1 sex ratio. As such, it is to the benefit of the wasp to be a reproductive queen as opposed to a worker, if feasible.
P. annularis was the first wasp which did not form large colonies to be observed storing honey in the autumn. The wasps store the honey over the winter to facilitate their survival in colder months and assist in the recognition of sisters, which will help construct new nests near their original one. The caching begins in early to midautumn, after which time the wasps retreat from the nest to hibernacula when the temperature drops below about 5 °C. They return to the nests when the weather permits, such as on warmer days. This behavior exposes P. annularis to attack from other insects of the same species, wasps of other species, such as those of the genus Vespula , and from mammals. However, Polistes species have evolved to hide their nests from most mammals or put them in areas as to make them inaccessible. Invading insects are attacked. Despite the fact that birds are common enemies of polistine wasps, none has been observed attacking nests for honey. The wasps may either gorge on the honey, or ration it, given that they are social insects. Additionally, wasps with nests containing honey are significantly more likely to survive the cold winter than those wasps whose nests do not contain honey.
Despite morphological similarities,queens and workers exhibit different behaviors over the winter. Queens overwinter, whereas workers do not. This difference in behavior may be s a direct consequence of the dominance hierarchy. Experimental treatment of wasps to cold conditions resulted in increased trehalose in both sexes, though females also increased levels of glucose and fructose, while males maintained or decreased these levels. Wasps at normal foraging temperature showed significantly lower carbohydrate levels than wasps treated at colder temperatures. In addition, exposing P. annularis to low temperatures over a two-week period caused many workers, but no foundresses and few males, to die. Foundresses appear to have greater glycogen storage capability than workers, helping them survive low temperatures. Males often have higher glucose, fructose, and trehalose levels higher than those of queens, indicating that mating may continue into autumn or winter. P. annularis cannot tolerate frost, though it has been shown to be able to survive at temperatures below the minimum temperature in the area in which it resides.
As new nests are established by P. annularis, many behavioral characteristics from the prior nest are taken to the new one. Notably, related siblings tend to aggregate together and go to the same nest. However, unlike in other Hymenoptera (eusocial insects), these wasps tend to act as independent agents; while the queen is at the top of the dominance hierarchy, the other wasps may lay eggs and forage for themselves as they see fit. As queens or foundresses evict other females, the aggregations begin to dissolve.
P. annularis females select a new nest site every year; they never use the same nest twice. The site is often within several meters of the previous one. Nests have been seen on cliffs and buildings, and less commonly in trees and on shrubs. Occasionally, wasps construct a new nest on the face of the old one, but they do not use the old one to store larvae. The old nest probably is not reused because it is often damaged, dirty, and parasitized in the late summer or winter. Other animals, such as moths, may use the empty nest during the winter.
Being a paper wasp, P. annularis gathers wood fibers to construct the new nest. The queen typically remains on the nest while subordinates search for wood. Fibers are often acquired by scraping the surface with the mandible, and mixing the resulting fibers with saliva to create a pulp. The pulp is added to the nest in a consistent manner.
When it comes to identifying how related a worker is to other workers, in P. annularis, this ability seems to be largely absent, or they are unable to make use of it to good effect. This comes at the cost of being able to especially aid closer relatives and thereby improve inclusive fitness. A super-sister relationship is one where sisters come from the same set of two parents (the same mother and father). Another way to consider this relationship is that they are full sisters instead of half sisters. Super sisters are related to each other genetically by three-fourths due to the specific sexual reproduction process among the Hymenoptera. Nonsuper-sisters have much lower relatedness by comparison. Therefore, preferentially helping one’s super-sisters is much better for inclusive fitness, but P. annularis seems not to follow this behavior when deciding which spring nest to join. The novel nests in springtime come from the same natal nests of the preceding fall, and generally the population of wasps in a new nest all have the common background of being from the same natal nest, but when two or more spring nests are derived from the same fall natal nest, workers may choose whichever nest they wish to join in the spring. Strangely, it seems, they do not show any preference for the nest whose members to which they are most genetically related.
For several reasons, P. annularis tends to form nests in crowded clumps. The species prefers overhangs that minimize sunlight exposure and flooding, and are near a body of water. This constraint means only a few locations are suitable for nesting. Consequently, aggregations of multiple nests tend to form on the same overhang in a very crowded manner. One cost of this crowding is direct reproductive competition between colonies. This takes the form of a usurpation of the current colony queen by a female from another colony. A foreign female can arrive at the nest, fight the reigning queen to the death or until the current queen is banished or becomes a subordinate, and then takes over the role of reproducing the majority of offspring in the colony. No selfish herd advantage is seen for a colony to be in the center of the aggregation, whereby the center would be safer than the periphery from predators, whereas in Ropalidia plebeiana , another species that forms nest aggregations, the entire nest aggregation is protected more so from predators.However, the cost of reproductive competition is increased for colonies in the center of the aggregation relative to colonies closer to the edge. Also, no advantage exists for a new colony to be established in close proximity to its preceding natal colony. P. annularis seems to nest in aggregations only because viable nesting locations are greatly limited.
As with many other species in the Hymenoptera, as well as other polistine wasps,P. annularis has been noted to engage in altruistic behavior. For example, despite the lack of drastic morphological differentiation between workers and foundresses, and the benefits procured by a worker becoming a foundress on a new nest, a worker may lay less than 10% as many eggs as her queen, independent of the number of females on the nest. This results in vastly decreased inclusive fitness for the worker and greatly increased inclusive fitness of the foundress, even if the sisters are related by a factor of 0.75, the maximum possible relatedness for outbred sisters. The workers acting in such a manner may create a direct cost upon which selection can act. However, evidence for this has been scant, and researchers are currently investigating why and how such levels of altruism are sustained in P. annularis.
Due to the dominance hierarchy, the queen leaves the nest as little as possible, and has the other wasps forage on her behalf. In small groups of wasps (two to three foundresses), the queen may be forced to forage. As workers emerge, they take over the role of foraging. P. annularis preys on moths, butterflies, flies, and other insects. Unlike other wasps in the genus, P. annularis generally takes its food from wooded areas, and not from fields. However, prey represents only 20% of food resources; the other 80% is liquid.P. annularis preys on caterpillars from a large number of lepidopteran families, including the Arctiidae, Saturniidae, Geometridae, Limacodidae, Lymantriidae, Notodontidae, Nymphalidae, Sphingidae, Erebidae, Noctuidae, Amphisbatidae, and Elachistidae. P. annularis tends to forage primarily in trees.
Ants, birds, and raccoons are predators of P. annularis.The principle predator is the ant. It is parasitized by Elasmus polistis and the moth Chalcoela iphitalis . P. annularis defends itself with venomous stingers. Antigen 5, which is present in their venom, is a major allergen. The nest pedicel contains lipids that provoke a necrophoric response from ants, protecting the nest from ant invasion.
The Polistinae are eusocial wasps closely related to the more familiar yellow jackets, but placed in their own subfamily, containing four tribes; with some 1100 species total, it is the second-most diverse subfamily within the Vespidae, and while most species are tropical or subtropical, they include some of the most frequently encountered large wasps in temperate regions. They are also known as paper wasps, which is a misleading term since other wasps also build nests out of paper, and because some epiponine wasps build theirs out of mud, nonetheless, the name "paper wasp" seems to apply mostly, but not exclusively, to the Polistinae, especially the Polistini. Many wasps, such as Polistes fuscatus,Polistes annularis, and Polistes exclamans, make their nests out of paper. Polistes annularis suspends its paper nests from cliff overhangs via a pedicel, whose free fatty acids induce the necrophoric response in ants and causes them to avoid the pedicel rather than cross and prey on the nest’s inhabitants. Polistes metricus foragers take off from their nests as if they already know how long their trip is. For short flights, they exit the nest flying horizontally, while for long flights they exit the nest flying straight up into a high altitude before pursuing their direction. Polistine brood cells are arranged in a hexagonal array, similar to the comb structure in a honey bee nest. At least one epiponine species stores honey in the comb, one of the only insects other than bees to store honey.
The European paper wasp is one of the most common and well-known species of social wasps in the genus Polistes. Its diet is more diverse than that of most Polistes species, giving it superior survival value over many other wasp species during a shortage of resources.
Polistes gallicus is a fairly common species of paper wasp found in various parts of Europe, excluding England, Denmark, and Scandinavia, from warmer climates to cooler regions north of the Alps. The distribution of P. gallicus also extends into northern regions of Africa, Israel, Iran, and even parts of China and Russia. Nests of these social insects are created in these various conditions. The Polistes species uses an oral secretion to construct their nests, which consist of a combination of saliva and chewed plant fibers. This structural mixture physically protects the nest from various harsh elements and from weathering over time.
Ropalidia marginata is an Old World species of paper wasp. It is primitively eusocial, not showing the same bias in brood care seen in other social insects with greater asymmetry in relatedness. The species employees a variety of colony founding strategies, sometimes with single founders and sometimes in groups of variable number. The queen does not use physical dominance to control workers; there is evidence of pheromones being used to suppress other female workers from overtaking queenship.
Polistes chinensis is a polistine vespid wasp in the cosmopolitan genus Polistes, and is commonly known as the Asian, Chinese or Japanese paper wasp. It is found in East Asia, in particular China and Japan. The subspecies P. chinensis antennalis is an invasive species in New Zealand, having arrived in 1979.
Polistes metricus is a wasp native to North America. In the United States, it ranges throughout the southern Midwest, the South, and as far northeast as New York, but has recently been spotted in southwest Ontario. A single female specimen has also been reported from Dryden, Maine. Polistes metricus is dark colored, with yellow tarsi and black tibia. Nests of Polistes metricus can be found attached to the sides of buildings, trees, and shrubbery.
Polistes fuscatus, whose common name is the golden or northern paper wasp, is widely found throughout southern Canada, the United States, and Central America. It often nests around human development. However, it greatly prefers areas in which wood is readily available for use as nest material, therefore they are also found near and in woodlands and savannas. P. fuscatus is a social wasp that is part of a complex society based around a single dominant queen along with other cofoundresses and a dominance hierarchy.
Polistes exclamans is a social wasp and is part of the family Vespidae of the order Hymenoptera. It is found throughout the United States, Mexico, the Bahamas, Jamaica and parts of Canada. Due to solitary nest founding by queens, P. exclamans has extended its range in the past few decades and now covers the eastern half of the United States, as well as part of the north. This expansion is typically attributed to changing global climate and temperatures. P. exclamans has three specific castes, including males, workers, and queens, but the dominance hierarchy is further distinguished by age. The older the wasp is, the higher it is in ranking within the colony. In most P. exclamans nests, there is one queen who lays all the eggs in the colony. The physiological similarities between the worker and queen castes have led to experiments attempting to distinguish the characteristics of these two castes and how they are determined, though males have easily identifiable physiological characteristics. Since P. exclamans live in relatively small, open combed nests, they are often subject to predators and parasites, such as Chalcoela iphitalis, Elasmus polistis, and birds. P. exclamans have defense and recognition strategies that help protect against these predators and parasites.
One of two types of red paper wasp, Polistes carolina is a species of social wasp in the family Vespidae. They are most commonly found in the eastern US from Texas through Nebraska. The wasp's common name is due to the reddish-brown color of its head and body. Red paper wasps are known to construct some of the largest nests of any wasp species and prefer to build their nests in protected spaces.
Belonogaster juncea juncea is a subspecies of Belonogaster juncea and is classified as a primitively eusocial wasp, meaning that the species is social while exhibiting a morphology that is indistinguishable from that of other castes. It is also classified as a type of African Paper Wasp. Many of the studies relating specifically to B. j. juncea take place at the University of Yaoundé in Cameroon.
Polistes instabilis, a type of paper wasp, is a neotropical, eusocial wasp that can be found in tropical and subtropical areas such as Central America and South America. It can be easily identified with its characteristic yellow, brown, and reddish markings, and it builds nests made from chewing plant fibers and making them into paper.
Polistes nimpha is a eusocial paper wasp found all over Europe, with particular sightings in Turkey, Finland, Estonia, and Latvia. It is also found in northern Africa, Pakistan, Iran, India, Kazakhstan, Mongolia, and China. The climate in these areas is relatively cold and snowy in the winter, while summers are usually hot and dry, with steppe vegetation. Polistes nimpha colonies are relatively small and easily manipulated.
Polistes bellicosus is a social paper wasp from the order Hymenoptera typically found within Texas, namely the Houston area. Like other paper wasps, Polistes bellicosus build nests by manipulating exposed fibers into paper to create cells. P. bellicosus often rebuild their nests at least once per colony season due to predation.
Belonogaster petiolata is a species of primitively eusocial wasp that dwells in southern Africa, in temperate or subhumid climate zones. This wasp species has a strong presence in South Africa and has also been seen in northern Johannesburg. Many colonies can be found in caves. The Sterkfontein Caves in South Africa, for example, contain large populations of B. petiolata.
Polistes biglumis is a species of social wasp within Polistes, the most common genus of paper wasp. It is distinguished mainly by its tendency to reside in montane climates in meadows or alpine areas. Selection pressure from the wasp's environment has led to several idiosyncrasies of its behavior and life cycle with respect to its relative species in the genus Polistes. It alone among paper wasps is often polyandrous. In addition, it has a truncated nesting season that gives rise to unique competitive dynamics among females of the species. P. biglumis wasps utilize an odor based recognition system that is the basis for all wasp to wasp interaction of the species. The wasp's life cycle is highly intertwined with that of Polistes atrimandibularis, an obligate social parasite wasp that frequently invades the combs of P. biglumis wasps.
Polistes sulcifer is a species of paper wasp in the genus Polistes that is found in Italy and Croatia. It is one of only three known Polistes obligate social parasites, sometimes referred to as "cuckoo paper wasps", and its host is the congeneric species Polistes dominula. As an obligate social parasite, this species has lost the ability to build nests, and relies on the host workers to raise its brood. P. sulcifer females use brute force, followed by chemical mimicry in order to successfully usurp a host nest and take over as the queen.
Polistes japonicus is a eusocial paper wasp found in Japan. It was first described by Henri Louis Frédéric de Saussure in 1858. It is closely related to Polistes formosanus. This species lives in small colonies with few workers and a foundress queen. Nests of these wasps are sometimes used as a traditional medicine in Korea, China, and Japan.
Polistes versicolor is a subtropical social wasp within Polistes, the most common genus of paper wasp. The most widely distributed South American wasp species, P. versicolor is particularly common in the Southeastern Brazilian states. This social wasp is commonly referred to as the yellow paper wasp due to the distinct yellow bands found on its thorax and abdomen. The P. versicolor nest, made of chewed vegetable fiber, is typically a single, uncovered comb attached to the substratum by a single petiole. The yellow wasp is frequently found in urban areas. New nests and colonies are usually founded by an association of females, sometimes in human buildings. The P. versicolor colony cycle broadly ranges from 3 to 10 months, although there appears to be no relationship between the colony's development and the season of the year. While yellow paper wasps do have clear annual colony cycles, many young queens have the opportunity to hibernate during the winter, forming optional winter aggregations. Dominance hierarchies within these aggregations are characterized by physical aggression of the dominant female(s) towards the associated females, who tend to be sisters. Wagging movements are also often used as a form of communication within the colony. The yellow paper wasp is generally predatory, capturing a wide range of insects, although it often feeds on pollen and honey as well. Therefore, P. versicolor can be useful as a pollinator or as effective pest control.