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Background: The poly-sensitization to Hymenoptera venom makes it difficult to select genuine allergens for immunotherapy and increases patients' costs. The objective of this study was to determine the culprit allergen in dual or triple-sensitized patients to three Hymenoptera venoms through molecular diagnosis and evaluating the results of incorporating the molecular diagnosis with skin tests. Methods: Thirty-two patients with anaphylactic reactions and dual or triple-sensitization to Hymenoptera venoms in skin tests entered this study. IgE-sensitization to whole extracts and molecules of Apis mellifera (Api m), Vespula vulgaris (Ves v), and Polistes dominulus (Pol d) was evaluated utilizing ALEX or ImmunoCAP. Results: Twenty-nine patients (90.6%) were male. IgE-sensitization to at least one of the allergenic molecules related to Apis mellifera, Vespula vulgaris, and Polistes dominulus was seen in 59.4, 53.1, and 21.9%, respectively. Among 32 patients, 14 (43.8) and 8 (25%), were mono-sensitized to Api m and Ves v components in ALEX, respectively. Double sensitization to Hymenoptera was identified in 18.8% of patients in ALEX. Api m 1+/Api m 2−/Api m 10− and Ves v 1+/Ves v 5+ demonstrated the most prevalent sensitizations patterns in our patients. Conclusions: The molecular diagnosis of IgE-sensitization to Hymenoptera venoms can be valuable, especially in patients who show dual or triple-sensitization in skin tests, as the ALEX results revealed mono and double-sensitization to Hymenoptera venoms in 22 and 6 patients, respectively. Regarding the high cost and adverse reactions of venom immunotherapy, especially for two or three venoms, incorporating the molecular diagnosis alongside skin tests for accurate diagnosis of the culprit venom could help decrease costs for patients. [ABSTRACT FROM AUTHOR]

The European paper wasp, Polistes dominula (Christ) (Hymenoptera: Vespidae), directly competes with native Polistes and is a safety concern for workers and homeowners. A previous investigation of Polistes behavior found that a portion of wasps died after consuming a solution of pear ester, a compound commonly found in fruits that is considered non-toxic to humans. The goal of our study was to corroborate those preliminary observations and investigate the toxicity of pear ester to P. dominula. Two experiments were performed. First, 3 wasp castes were fed 17% sugar water, or sugar water mixed with 0.5%, 1.0%, 5.0%, or 10.0% (w/v) solutions of pear ester. Mortality after 24 h ranged from 0% among wasps fed sugar water only, to >10% among wasps that were fed pear ester. Mortality increased logarithmically with pear ester concentration. Pear ester toxicity differed among wasp castes, with <5% mortality recorded among fall gynes to >10% mortality among workers. The second experiment attempted to define the relationship between morbidity and volume of pear ester consumed by P. dominula workers. Although results confirmed that ingestion of pear ester causes death or paralysis of P. dominula workers, there was no clear relationship between volume of ingested pear ester and wasp morbidity. About 80% of P. dominula were unaffected by pear ester despite consuming large quantities of the solution. This is the first study to demonstrate lethal effects of pear ester compound and may indicate its potential as an insecticide for paper wasps. La avispa cartonera europea, Polistes dominula (Christ) (Hymenoptera: Vespidae), compite directamente con las Polistes nativas y, además, es una preocupación de seguridad para trabajadores y familias en sus casas. Una investigación previa sobre el comportamiento de Polistes, encontró que algunas de las avispas morían después de consumir una solución de éster de pera, un compuesto comúnmente encontrado en frutas y que no es considerado tóxica para humanos. El objetivo de nuestro estudio fue corroborar esas observaciones preliminares e investigar la toxicidad del éster de pera para P. dominula. Se realizaron 2 experimentos. Primero, 3 castas de avispas fueron alimentadas con soluciones de 17% agua azucarada, o agua mezclada con 0.5%, 1.0%, 5.0% y 10.0% (p/v) con éster de pera. La mortalidad después de 24 horas varió desde 0% entre avispas alimentadas solamente con agua azucarada, a >10% entre avispas a las cuáles se les dio éster de pera. La mortalidad aumentó logarítmicamente con la concentración de éster de pera. La toxicidad del éster de pera varió entre las castas de avispas, con una mortalidad registrada <5% entre hembras reproductivas de otoño a >10% entre obreras. El segundo experimento intentó definir la relación entre morbilidad y volumen de éster de pera consumido por obreras de P. dominula. Aunque los resultados confirmaron que la ingesta de éster de pera causa la muerte o parálisis de obreras de P. dominula, no hubo una relación clara entre el volumen ingerido de éster de pera y morbilidad. Cerca del 80% de P. dominula no fue afectado por el éster de pera, a pesar, de haber consumido grandes cantidades de la solución. Este es el primer estudio que demuestra que la ingestión de éster de, pero por un insecto causa parálisis o muerte. Este es el primer estudio que demuestra efectos letales del compuesto de éster de pera y puede indicar su potencial como insecticidas para avispas papeleras. [ABSTRACT FROM AUTHOR]

Simple Summary: The heat-loving paper wasp Polistes dominula builds small nests in sheltered places in quite differing habitats, providing a favorable microclimate for brood development. Their careful choice of the nesting site enables them to keep the nest and brood temperature above the ambient air temperature. In temperate Austrian (Central European) climates, the cooling efforts of the adult wasps keep the mean comb temperature from exceeding approximately 39 °C, which seems to be a threshold for optimal development. Measurement of the nest and the body temperature of the wasps at typical nesting sites revealed a close relationship with the air temperature at the nests but a suboptimal correlation with climate data from a local standard weather station or model-generated macroclimate data. The comparison emphasizes the importance of microclimate measurements if it is to judge the vulnerability of insects to climate change. The paper wasp Polistes dominula is a thermophilic species originating from the Mediterranean climate, but is now widely spread in Europe. They live in quite differing habitats; and as synanthropic species, they have been established in human settlement areas. They build a single small comb at protected places with a favorable microclimate. We measured the temperature of the wasps, the nests and their environment at typical nesting sides in Austria (Europe) in the temperate climate, in order to reveal relationships between nest and body temperature and the habitats' microclimate. The temperatures of the comb and of the wasps' body were in a wide range (~20–37 °C) above the ambient air temperature at the nest. This is an advantage as higher temperatures accelerate the development speed of the brood. However, the mean comb temperature did not exceed approximately 38.6 °C. This was managed by cooling efforts of the adult wasps. The ambient air temperature near the nest (~1–2 cm) was always clearly elevated above the ambient air temperature at a local standard weather station in the habitat. A comparison with climate-model-generated macroclimate data revealed the necessity of measuring microclimate data for a reliable description of the insects' thermal environment. [ABSTRACT FROM AUTHOR]

The study of social wasp biology is often focused on understanding the factors involved in the evolution of social behavior. However, despite the importance of parasitism for the fitness of social insect colonies, little is known about the presence of parasitic protozoan infections in Neotropical social wasp populations. Herein, we report the first recorded occurrence of eugregarines in the midgut of the paper wasp Polistes versicolor. Our study shows 46% of the adults (n = 50) in the studied population were infected with gregarine trophozoites. No protozoans were identified in any of the sampled larvae (n = 14). This new record may indicate the existence of a new taxon within Order Eugregarinorida. [ABSTRACT FROM AUTHOR]

Honey is a healing compound produced by the Apidae bees. So far, the only genus of Apis with 9 known species worldwide is a honey bee. But species of paper wasps in the Vespidae can also produce honey. This research was conducted to study and identify the species of paper wasp honey producer in the South of Kerman. For this purpose, the activity areas of this wasp were identified, and specimens of this paper wasp were collected for species identification. The specimens were identified by keys and related articles and Confirmed by Dr. James M. Carpenter at the American Museum of natural history. Parapolybia escalerae (Meado-Waldo) was described by Mead-Waldo in the London British Museum in 1911 as a single female specimen from southwestern Iran. The World distribution of this paper wasp is in Pakistan, Turkey, and Iran. According to the results of this study, the species Parapolybia escalerae (Meado-Waldo, 1911) was identified for the first time in southeastern Iran (south of Kerman). This species was distributed south of Kerman from the tropical foothills of Jabalbarz Mountains (southern Jabalbarz to Mohammadabad) and Bahraseman. Parapolybia escalerae is introduced in the world as a paper wasp species of a honey producer. The paper wasp is known as dry or chocolate honey and has medicinal use. In this study, the male and queen specimens were collected and identified for the first time. This study found that this species of paper wasp, like the Apis florea, produces wild honey. A. florea has open nests and small colonies of a single comb, but P. escalerae is in the dark space of mountains and cliffs and produces many combs. The activity of this species was mostly observed on the Ziziphus sp. and Pistacia terebinthus trees. This paper wasp has a social life and includes three forms of queens, workers, and males. So far, only two species of Honey producing paper wasps have been reported in South America, including Brachygastra mellifica (Say, 1837), known as the Mexican Honey Wasp and Brachygastra lecheguana (Latreille, 1824), which are paper wasps belonging to the subfamily Polistinae. These two species have round nests and build their nests on tall trees and the ground in open spaces. Their honey has medicinal use in different regions of South America and is collected by local people. The paper wasp species P. escalerae works in the crevices of the rocks and has several flat combs. In Iran, the local people of the southern regions of Iran use this honey as medicine to treat respiratory diseases. [ABSTRACT FROM AUTHOR]

Paper wasps are a model system for the study of social evolution due to a high degree of inter- and intraspecific variation in cooperation, aggression, and visual signals of social status. Increasing the taxonomic coverage of genomic resources for this diverse clade will aid comparative genomic approaches for testing predictions about the molecular basis of social evolution. Here, we provide draft genome assemblies for two well-studied species of paper wasps, Polistes exclamans and Mischocyttarus mexicanus. The P. exclamans genome assembly is 221.5 Mb in length with a scaffold N50 of 4.11 Mb. The M. mexicanus genome assembly is 227 Mb in length with a scaffold N50 of 1.1 Mb. Genomes have low repeat content (9.54–10.75%) and low GC content (32.06–32.4%), typical of other social hymenopteran genomes. The DNA methyltransferase gene, Dnmt3  , was lost early in the evolution of Polistinae. We identified a second independent loss of Dnmt3 within hornets (genus: Vespa). [ABSTRACT FROM AUTHOR]

Mirror studies have uncovered evidence for self-awareness in several non-human animals; however, this approach has not been extended to invertebrates. Here, we examined mirror responses of Polistes paper wasps, insects with high social cognitive abilities. We used a highly replicated design, exposing wasps to mirror self-recognition (MSR) test stimuli (mirror, facial marking) and several control stimuli (non-reflective surfaces, invisible marks, and sham marks). We found that nest-founding queen wasps respond to mirrors with increases in antennation and touching over non-reflective surfaces. Visible marks also resulted in more exploratory behaviours (antennating and touching the mirror), but decreases in self-directed behaviours typically used as indicators of MSR. While this experiment does not support the notion that wasps possess self-awareness, it shows that wasps respond to subtle alterations in their visual environment and appearance with exploratory behaviour. This work thus increases our understanding of insects' cognitive abilities, suggesting high levels of perceptual richness. [ABSTRACT FROM AUTHOR]

A nest of a paper wasp, Polistes(Gyrostoma)sp., infested by the pyralid Hypsopygia mauritialis was dissected and examined in detail. The nest was found in Kagoshima, southern Japan, and collected in mid-September, 2021. Cell walls of the nest comb had many holes, and no brood or meconia remained, probably because of destruction from the feeding activities of the larval moths. The nest had a strange structure(fecal dangler)suspended from the nest comb: the fecal dangler was about 10 cm long and mainly comprised fecal grains of the moth mixed with pupal exuviae of the moth and fragments of wasp cocoons woven together with silk. The nest comb and fecal dangler contained 43 live moth larvae(only 13 of which were vigorous)and 8 live pupae. A total of at least 123 pupal exuviae were present. The feeding behavior and the function of the fecal dangler are discussed, and compared with other cases of Polistes nests infested by Hypsopygia species previously reported. [ABSTRACT FROM AUTHOR]

Ropalidia marginata is a common primitively eusocial wasp in peninsular India. Their colonies contain a single egg-laying queen and several non-egg-laying workers. Queens and workers are morphologically indistinguishable, and individuals can change from one role to the other. Unlike most primitively eusocial species, queens of R. marginata are docile, non-aggressive and non-interactive. Nevertheless, the queens maintain a complete reproductive monopoly mediated by non-volatile pheromones. Upon the death or removal of the queen, one worker becomes temporarily hyper-aggressive and becomes the next queen within about a week; we refer to her as the 'potential queen'. Because only one individual becomes hyper-aggressive and reveals herself as the potential queen, and the other wasps never challenge her, we have been much interested in identifying the potential queen in the presence of the queen. However, we have failed to do so until recently. Here, we recount the four decades of search for the potential queen, ending with the recent resolution that emerged from applying the novel technique of multilayer network analysis. Identifying the potential queen in the presence of the previous queen is now possible by integrating behavioural information from multiple social situations to form a holistic view of the social structure of the wasps. [ABSTRACT FROM AUTHOR]

The ability to recognize others is a frequent assumption of models of the evolution of cooperation. At the same time, cooperative behavior has been proposed as a selective agent favoring the evolution of individual recognition abilities. Although theory predicts that recognition and cooperation may co-evolve, data linking recognition abilities and cooperative behavior with evidence of selection are elusive. Here, we provide evidence of a selective link between individual recognition and cooperation in the paper wasp Polistes fuscatus through a combination of clinal, common garden, and population genomics analyses. We identified latitudinal clines in both rates of cooperative nesting and color pattern diversity, consistent with a selective link between recognition and cooperation. In behavioral experiments, we replicated previous results demonstrating individual recognition in cooperative and phenotypically diverse P. fuscatus from New York. In contrast, wasps from a less cooperative and phenotypically uniform Louisiana population showed no evidence of individual recognition. In a common garden experiment, groups of wasps from northern populations formed more stable and individually biased associations, indicating that recognition facilitates group stability. The strength of recent positive selection on cognition-associated loci likely to mediate individual recognition is substantially greater in northern compared with southern P. fuscatus populations. Collectively, these data suggest that individual recognition and cooperative nesting behavior have co-evolved in P. fuscatus because recognition helps stabilize social groups. This work provides evidence of a specific cognitive phenotype under selection because of social interactions, supporting the idea that social behavior can be a key driver of cognitive evolution. [Display omitted] • Cooperation and signal diversity covary across the geographic range of a paper wasp • The ability to recognize individuals is related to cooperation and signal diversity • Individual recognition stabilizes social groups • Selection on social cognition genes is stronger in more cooperative populations Using three distinct approaches—a geographic cline of signal diversity and cooperation, common garden behavioral experiments, and genomic analyses of selection—Tumulty et al. show that cooperation favors the evolution of individual recognition in a cooperatively breeding paper wasp. [ABSTRACT FROM AUTHOR]

Why workers forfeit direct reproduction is a crucial question in eusocial evolution. Worker reproduction provides an excellent opportunity to understand the mechanism of kin conflict resolution between the queen and workers. We evaluated behavioral and physiological differences among females in the paper wasp Polistes chinensis antennalis to examine why some workers reproduce under queenright conditions. Reproductive workers were old and foraged less early in the season; their cuticular hydrocarbon (CHC) profiles overlapped with those of queens but were significantly different. The distinct CHC profile of the eggs of the queen likely represented a cue for policing against those by workers. Juvenile hormone (JH) and dopamine seemed to be associated with gonadotropic function, and the JH level of reproductive workers was similar to that of the queen. The high JH level of reproductive workers likely facilitated their reproduction even under queenright conditions. Gene expression levels of the queen and reproductive workers differed only in vitellogenin. These results suggest that worker reproduction is facilitated by an increase in JH level; however, CHC is not a fertility-linked signal, but a queen-linked signal; consequently, reproductive workers without a queen-linked signal might be allowed to stay within the colony. [ABSTRACT FROM AUTHOR]

Purpose: To compare the outcomes of ocular injuries of hornets and paper wasps’ stings.Study design: Retrospective case series.Methods: Patients diagnosed with ocular injuries sustained by bee stings at Miyata Eye Hospital (Miyazaki, Japan) between August 2000 and July 2016 were enrolled. Retrospective data regarding type of bee, visual acuity, and treatment were collected from medical records. Outcomes of the hornet and wasp groups were compared.Results: Five eyes of 5 patients (3 men, 2 women; mean age 44.6±21.2 years [range 9-62 years]) were enrolled. The mean follow-up period was 50.6 ± 57.6 months (range 4 days to 121 months). The causative bee was hornet in 3 cases and wasp in 2. The anterior chamber was irrigated in 2 patients, both from the hornet group. The best-corrected visual acuity at the final visit was no light perception, light perception, and (0.02) in the hornet group, (1.5) and (1.2) in the wasp group.Conclusions: The hornet group exhibited significantly worse prognosis than the wasp group. Identifying the type of bee is important in establishing prognosis. [ABSTRACT FROM AUTHOR]

The founding individuals of a new group or lineage are uniquely poised to have long-lasting effects on their descendants. Here we explore how the behavioural traits of new foundresses influence their task allocation strategies and the downstream collective behaviour of their colonies. We collected individual paper wasp ( Polistes metricus ) queens from the wild and measured their boldness, aggressiveness, exploration, activity and time budgets in the laboratory. We then provided queens with food and nest materials and waited for their workers to eclose. We subsequently tested for links between queen behavioural traits (e.g. boldness, aggressiveness) and the collective aggressiveness of their colonies, as estimated by the number of workers that responded to and stung a model predator. We found that bolder queens (i.e. queens that were less likely to leave their nests after repeated exposure to an agonistic stimulus) spent more time nest guarding, reared more workers and produced groups that were less responsive to a model predator. Thus, there appears to be parent–offspring, or queen–worker, resemblance in the degree to which individuals remain on their nests in different social contexts (solitary queen versus queen + her worker group). To our knowledge this represents the first study to explicitly test for links between individual variation in foundress behaviour, worker production and intercolony collective behaviour; the results highlight the possibility that cross-contextual and transgenerational behavioural links could be a reasonably common and potentially important phenomenon in complex societies. [ABSTRACT FROM AUTHOR]

Additions to the knowledge of the paper wasp genus Polistes (Polistella) (Hymenoptera: Vespidae: Polistinae) from the northern part of Vietnam are presented. The males of two species, P. affinis Gusenleitner, 2006, and P. curcipunctum Nguyen, Kojima & Saito, 2011, are described for the first time. The nests of P. affinis Gusenleitner, 2006, and P. nipponensis Pérez, 1905, are also described. [ABSTRACT FROM AUTHOR]

Wasps of the genus Polistes build combs without any cover and hence are insufficiently protected against temperature fluctuations. Due to this fact, different types of thermoregulation of Polistes dominula nests were investigated using the modern method of thermography. The study of active mechanisms for nest thermoregulation revealed no brood incubation or clustering behaviour of P. dominula . Furthermore, we found out that wing fanning for cooling the nest was almost undetectable (4 documented cases). However, we could convincingly record that water evaporation is most effective for nest cooling. By the direct comparison of active (with brood and adults) and non-active (without brood and adults) nests, the start of cooling by water evaporation was detected above maximum outside temperatures of 25 °C or at nest temperatures above 35 °C. The powerful role of water in nest cooling was manifested by an average decrease of temperature of single cells of about 8 °C and a mean duration of 7 min until the cells reached again their initial temperature. The investigation of passive thermoregulatory mechanisms revealed that the architecture of the nest plays an important role. Based on the presented results, it can be assumed that the vertical orientation of cells helps maintaining the warmth of nests during the night, whereas the pedicel assists in cooling the nest during the day. Therefore, our study of nest thermoregulation has revealed that P. dominula wasps regulate the temperature of their nest actively by evaporative cooling and passively by a careful site selection and the architecture of their nests. [ABSTRACT FROM AUTHOR]

Comparative genomics of social insects has been intensely pursued in recent years with the goal of providing insights into the evolution of social behaviour and its underlying genomic and epigenomic basis. However, the comparative approach has been hampered by a paucity of data on some of the most informative social forms (e.g. incipiently and primitively social) and taxa (especially members of the wasp family Vespidae) for studying social evolution. Here, we provide a draft genome of the primitively eusocial model insect Polistes dominula, accompanied by analysis of caste-related transcriptome and methylome sequence data for adult queens and workers. Polistes dominula possesses a fairly typical hymenopteran genome, but shows very low genomewide GC content and some evidence of reduced genome size. We found numerous caste-related differences in gene expression, with evidence that both conserved and novel genes are related to caste differences. Most strikingly, these -omics data reveal a major reduction in one of the major epigenetic mechanisms that has been previously suggested to be important for caste differences in social insects: DNA methylation. Along with a conspicuous loss of a key gene associated with environmentally responsive DNA methylation (the de novo DNA methyltransferase Dnmt3), these wasps have greatly reduced genomewide methylation to almost zero. In addition to providing a valuable resource for comparative analysis of social insect evolution, our integrative -omics data for this important behavioural and evolutionary model system call into question the general importance of DNA methylation in caste differences and evolution in social insects. [ABSTRACT FROM AUTHOR]

Attractants are sought for trapping of Polistes spp. paper wasps when they are pestiferous. The serendipitous capture of Polistes metricus Say and Polistes bellicosus Cresson in traps baited with a wine/vinegar mixture for spotted wing drosophila, Drosophila suzukii (Matsumura) prompted experiments to determine the nature of the wasp response. Both wasp species were captured in subsequent field tests in traps baited with the same mixture of wine plus vinegar, and not in unbaited traps. Polistes bellicosus responses to wine, vinegar, ethanol (as a major volatile of wine), and acetic acid (as a major volatile of vinegar) were evaluated using a Y-tube olfactometer. In the olfactometer, P. bellicosus wasps were attracted to wine and not to vinegar. They also preferred wine alone to wine with vinegar, and were attracted to ethanol. Female wasps were deterred by acetic acid. In field tests comparing traps baited with wine, vinegar and a combination of the 2 materials, P. bellicosus and Polistes fuscatus (Fab.) were captured in traps baited with wine, but were not trapped with vinegar. The inclusion of vinegar with wine did not improve bait attractiveness in the field. We conclude that the paper wasp response to the D. suzukii bait of wine plus vinegar was largely the result of the wasp response to wine. This work constitutes the first demonstration of an attractive bait that can be used to trap P. bellicosus and P. metricus in situations where they are pestiferous, and suggests a potential source of a chemical attractant based on wine volatiles. [ABSTRACT FROM AUTHOR]

Several eusocial wasps are prominent invaders to remote islands. The paper wasp Polistes chinensis antennalis is native to East Asia, was introduced to New Zealand in 1979 and has expanded its distribution there. This provides an excellent opportunity to examine the impacts of an initial bottleneck and subsequent expansion on genetic structure. We analysed and compared the genetic population structures of the native (Japan and South Korea) and invasive New Zealand populations. Although 94% of individuals had shared haplotypes detected across both populations, the remaining 6% had private haplotypes identified in only one of the three countries. The genetic variation at microsatellite loci was lower in New Zealand than in native countries, and the genetic structure in New Zealand was clearly distinct from that in its native range. Higher frequencies of diploid-male- and triploid-female-producing colonies were detected in New Zealand than in the native countries, showing the reduction in genetic variation via a genetic bottleneck. At least two independent introductions were suggested, and the putative source regions for New Zealand were assigned as Kanto (central island) and Kyushu (south island) in Japan. Serial founder events following the initial introduction were also indicated. The estimated dispersal distance between mother and daughter in New Zealand was twice that in Japan. Thus, the introduction history of P. chinensis antennalis in New Zealand is probably the result of at least two independent introductions, passing through a bottleneck during introduction, followed by population expansion from the point of introduction. [ABSTRACT FROM AUTHOR]

In many signalling systems, intraspecific variation in recognition abilities is based on developmental stage, experience or caste. However, the occurrence of intraspecific variation in recognition has not been thoroughly examined in species with individual recognition. For example, previous work has shown that individual recognition is an important aspect of the social life of Polistes fuscatus (paper wasp) nest-founding queens, as individual recognition stabilizes dominance interactions and reduces aggression. To date, the potential for individual recognition among P. fuscatus workers has been largely ignored. Here, we explore whether there is intraspecific variation in individual recognition by testing P. fuscatus worker recognition abilities in a series of staged contests. The results indicate that P. fuscatus workers are capable of individual recognition: focal workers paired with previously encountered partners experienced significantly less aggression and more nonaggressive bodily contact than focal workers paired with unknown social partners. We propose two potential explanations for individual recognition among workers: (1) worker individual recognition may be favoured because it provides social benefits to workers, or (2) worker individual recognition may be a byproduct of selection for individual recognition in foundresses. Individual recognition is often considered a cognitively challenging form of recognition, so future studies that compare the sophistication of recognition across castes will be useful to assess whether there are more subtle differences in cognitive abilities or recognition behaviour between P. fuscatus nest-founding queens and workers. [Copyright &y& Elsevier]

Paper wasps negotiate over help using indicators of demand. Animal societies are composed of individuals whose genetic interests are often opposed. We conducted experiments on a cooperative paper wasp which reveal the behavioural rules by which group members settle these conflicts.Recent theory and empirical studies of avian biparental systems suggest that animals resolve conflict over parental care via a process of behavioral negotiation or “rules for responding.” Less is known, however, about whether negotiation over helping effort occurs in cooperatively breeding animal societies or whether behavioral negotiation requires a relatively large brain. In this study, we tested whether negotiation over help occurs in a social insect, the paper wasp Polistes dominulus, by recording individual responses to both observed and experimentally induced foraging returns by other group members. In our experiments, we manipulated food delivery to the nest in 2 ways: 1) by catching departing foragers and giving them larval food to take back to the nest and 2) by giving larval food directly to wasps on the nest, which they then fed to larvae, so increasing food delivery independently of helper effort. We found no evidence from Experiment 1 that helpers adjusted their own foraging effort according to the foraging effort of other group members. However, when food was provided directly to the nest, wasps did respond by reducing their own foraging effort. One interpretation of this result is that paper wasp helpers adjust their helping effort according to the level of offspring need rather than the work rate of other helpers. Negotiation based on indicators of demand rather than work rate is a likely mechanism to resolve conflict over investment in teams where helpers cannot observe each other’s work rate directly, as is commonly the case in insect and vertebrate societies. [ABSTRACT FROM PUBLISHER]

The mosaic brain evolution hypothesis predicts that the relative volumes of functionally distinct brain regions will vary independently and correlate with species' ecology. Paper wasp species (Hymenoptera: Vespidae, Polistinae) differ in light exposure: they construct open versus enclosed nests and one genus (Apoica) is nocturnal. We asked whether light environments were related to species differences in the size of antennal and optic processing brain tissues. Paper wasp brains have anatomically distinct peripheral and central regions that process antennal and optic sensory inputs. We measured the volumes of 4 sensory processing brain regions in paper wasp species from 13 Neotropical genera including open and enclosed nesters, and diurnal and nocturnal species. Species differed in sensory region volumes, but there was no evidence for trade-offs among sensory modalities. All sensory region volumes correlated with brain size. However, peripheral optic processing investment increased with brain size at a higher rate than peripheral antennal processing investment. Our data suggest that mosaic and concerted (size-constrained) brain evolution are not exclusive alternatives. When brain regions increase with brain size at different rates, these distinct allometries can allow for differential investment among sensory modalities. As predicted by mosaic evolution, species ecology was associated with some aspects of brain region investment. Nest architecture variation was not associated with brain investment differences, but the nocturnal genus Apoica had the largest antennal:optic volume ratio in its peripheral sensory lobes. Investment in central processing tissues was not related to nocturnality, a pattern also noted in mammals. The plasticity of neural connections in central regions may accommodate evolutionary shifts in input from the periphery with relatively minor changes in volume. © 2013 S. Karger AG, Basel [ABSTRACT FROM AUTHOR]

Discrimination among potential partners is a critical step in sexual selection to avoid wasting reproductive resources on an unsuitable mate. In the female-dominated hymenopteran societies males have often been regarded as ‘flying sperm containers’ spending all their time and energy in trying to acquire a mate. We investigated the male sexual preference for potential partners using as a model the primitively eusocial wasp Polistes dominula in which female caste is rather flexible and difficult to determine. By means of laboratory bioassays, we compared the males' behaviour towards females of different reproductive potential. Males were able to recognize female castes, strongly preferring reproductive females to workers, regardless of female age or health. The results show that in this species caste plays a key role in orienting male discrimination and preference, presumably through chemical cues, towards reproductive females both healthy and parasite-castrated. Overall, our study shows that social Hymenoptera males are not always ‘small mating machines’ eager to mate. [ABSTRACT FROM AUTHOR]

Theory on animal contests often assumes that individuals can rapidly and accurately assess their own resource-holding potential (RHP). In empirical work, individuals behave as if they ‘know’ their own RHP, but little is known about how such assessment occurs. Here, we test how juvenile hormone (JH) influences precontest behaviour in P. dominulus paper wasps. Previous work has shown that P. dominulus have variable black facial patterns that are a signal of agonistic ability and that JH influences fighting ability. In this experiment, we tested how JH influences rival challenge behaviour in the absence of direct social competition. Wasps were given the opportunity to challenge or avoid a model wasp guarding a patch of food. Individuals treated with the JH analogue methoprene were more likely to challenge rivals than were control individuals, and they also had a shorter latency to challenge than controls. However, hormone treatment was only one of multiple factors that influenced behaviour, suggesting that assessment prior to contests is based on the interplay between individual physiology and social context. Contest decisions were also dependent on a wasp's own facial pattern and mass, as well as the facial pattern of its rival. Interestingly, these complex assessment decisions occurred in the absence of direct social cues that could be acquired during a contest. These results are consistent with JH playing a role in self-assessment of RHP. Hormones such as JH are influenced by the physical and social environment, so they provide diverse information about relative RHP and may be commonly involved in assessment behaviour. [ABSTRACT FROM AUTHOR]

In the present study, the nest architectural patterns, elemental analysis and their behavior were carried out in three wasp species: Vespa velutina (Lepeletier), Polistes lavus (Cresson) and Sceliphron formosum (Smith) from the different localities of the Mansehra, Pakistan. The V. velutina nest was completely closed except for one opening for entry or exit with 1-10 layers of hexagonal cells inside the nest. The nests of P. lavus were found among bunches of leaves of trees with 1-5 layers and hexagonal cells same as in V. velutina. Nests of the S. formosum were pitcher-shaped, found in muddy places, and consisted of 1-10 cells. Social behavior of wasps showed strong foraging, defensive behaviors, pseudo-attack, subsequent erratic light, wing buzzing, mandibular pecking, abdominal pumping and abdominal twisting with highly developed parental care. It was concluded that the behaviors of these 3 wasp species was highly developed as compared with other insects. [ABSTRACT FROM AUTHOR]

Abstract: Social insect colonies contain attractive resources for many organisms. Cleptoparasites sneak into their nests and steal food resources. Social parasites sneak into their social organisations and exploit them for reproduction. Both cleptoparasites and social parasites overcome the ability of social insects to detect intruders, which is mainly based on chemoreception. Here we compared the chemical strategies of social parasites and cleptoparasites that target the same host and analyse the implication of the results for the understanding of nestmate recognition mechanisms. The social parasitic wasp Polistes atrimandibularis (Hymenoptera: Vespidae), and the cleptoparasitic velvet ant Mutilla europaea (Hymenoptera: Mutillidae), both target the colonies of the paper wasp Polistes biglumis (Hymenoptera: Vespidae). There is no chemical mimicry with hosts in the cuticular chemical profiles of velvet ants and pre-invasion social parasites, but both have lower concentrations of recognition cues (chemical insignificance) and lower proportions of branched alkanes than their hosts. Additionally, they both have larger proportions of alkenes than their hosts. In contrast, post-invasion obligate social parasites have proportions of branched hydrocarbons as large as those of their hosts and their overall cuticular profiles resemble those of their hosts. These results suggest that the chemical strategies for evading host detection vary according to the lifestyles of the parasites. Cleptoparasites and pre-invasion social parasites that sneak into host colonies limit host overaggression by having few recognition cues, whereas post-invasion social parasites that sneak into their host social structure facilitate social integration by chemical mimicry with colony members. [Copyright &y& Elsevier]

Although sexually selected ornaments are common across diverse taxa, little is known about mate choice and sexually selected ornamentation in social insects. Polistes dominulus paper wasps are a good system to study sexual selection, as males have a lek-based mating system as well as sexually dimorphic abdominal spots. Here, we demonstrate that the abdominal spots of male P. dominulus paper wasps function as signals in both inter- and intrasexual selection. Males with smaller, elliptically shaped spots were more dominant over male rivals and were more preferred by females than males with larger, irregularly shaped spots. Furthermore, experimental manipulation of male spots demonstrates that spot morphology acts as a signal. Males with experimentally reduced abdominal spots won a greater proportion of fights and were preferred by females as mates over control males. These results demonstrate that male ornaments are an important mediator of mating dynamics in P. dominulus paper wasps. They also highlight the importance of additional research examining sexually selected ornamentation in social insects. [Copyright &y& Elsevier]

Introduction: Aposematism is a defense system against predators consisting of the toxicity warning using conspicuous coloration. If the toxin production and aposematic coloration is costly, only individuals in good physical condition could simultaneously produce abundant poison and striking coloration. In such cases, the aposematic coloration not only indicates that the animal is toxic, but also the toxicity level of individuals. The costs associated with the production of aposematic coloration would ensure that individuals honestly indicate their toxicity levels. In the present study, we examine the hypothesis that a positive correlation exists between the brightness of warning coloration and toxicity level using as a model the paper wasp (Polistes dominula). Results: We collected wasps from 30 different nests and photographed them to measure the brightness of warning coloration in the abdomen. We also measured the volume of the poison gland, as well as the length, and the width of the abdomen. The results show a positive relationship between brightness and poison-gland size, which remained positive even after controlling for the body size and abdomen width. Conclusion: The results suggest that the coloration pattern of these wasps is a true sign of toxicity level: wasps with brighter colors are more poisonous (they have larger poison glands). [ABSTRACT FROM AUTHOR]

The macroparasite Xenos vesparum affects both the behaviour and the physical traits of its host, the social wasp Polistes dominulus. Female wasps, if parasitized, do not perform any social tasks and desert the colony to gather at specific sites, where the parasite mates; at the end of summer they form prehibernating clusters joined by healthy future queens to overwinter. Parasitized wasps become highly gregarious. In April, healthy wasps leave the aggregations to found new colonies, while parasitized wasps remain in overwintering groups and release parasites to infect wasp larvae only later in the season. We studied the prolonged gregarious behaviour of parasitized wasps and analysed the morphology of parasitized and healthy wasps in aggregations collected over a 7-year period to determine whether the parasite affects host size, wing symmetry, ovarian development and lipid stores. All parasitized wasps were smaller and had undeveloped ovaries and more wing fluctuating asymmetry than unparasitized wasps, irrespective of time of year, parasite load and parasite sex. If infected only by one or two X. vesparum females, the wasps had large fat bodies, which could facilitate their overwintering. In contrast, wasps infected by at least one male parasite had little lipid and died at the end of the summer. Thus, X. vesparum, may play a role in the fate of its host, by exploiting wasps'' tendency to form aggregations outside the colony and by altering its caste system, nutrient allocation, diapause timing and life span to achieve its own reproduction and dispersal. [ABSTRACT FROM AUTHOR]

Insect social parasites need to overcome host colonies’ defences to exploit their resources successfully. Sophisticated sensory deception mechanisms to break the host’s barriers have been repeatedly reported for many social parasites, possibly concealing the importance of open fighting, a more ancestral strategy. Understanding the relative importance of fooling and fighting is primarily challenging when the two strategies seem both available and advantageous. We focused on the paper wasp social parasite–host system Polistes sulcifer–P. dominulus, where both fooling and fighting have been suggested to play a role during usurpation contests. Host aggression is elicited by the chemical cues (hydrocarbons) that intruders bear on their cuticle. Parasites would benefit from reducing the amount of these cues before approaching the host colony. In addition, the parasites’ facial pattern has been shown to reduce the host’s aggressive reaction, probably by amplifying the mandibular width. We tested the occurrence of chemical and visual cheating through chemical analyses and laboratory usurpation trials, respectively. Usurping parasites did not conceal their identity by reducing cuticular hydrocarbons, nor did their facial pattern facilitate nest take-over. Contest outcome was instead predicted by the relative body size of the opponents. Fighting, rather than fooling, is therefore the strategy used by P. sulcifer usurping females. The importance of physical strength could thus explain why chemical or visual tricks do not play a role in taking over the host colony despite their potential usefulness. Our findings suggest that the evolution of sophisticated cheating mechanisms can be prevented by the ability to fight. [Copyright &y& Elsevier]

Obligate social parasite insects are specialized in exploiting the parental service of the workers of another social species by invading their colonies. As social insects are usually aggressive towards intruders, social parasites have to circumvent the host’s nestmate recognition system to enter the host colony successfully. Many studies on paper wasps have shown that, after host nest invasion, Polistes social parasites change their chemical profile to match the host’s odour, thus allowing their acceptance into its colony. However, a social parasite’s usurpation strategy may benefit from signals that reduce or eliminate the aggression of the host. We used lure presentation experiments to investigate whether Polistes sulcifer, a social parasite of the paper wasp P. dominulus, is able to reduce the aggressive reaction of its host. We found that the parasite lure elicited lower host aggressiveness than the conspecific lure, suggesting that parasite species have evolved cues able to inhibit host aggressiveness. We investigated separately the effects of chemical and visual patterns on host aggressiveness. The lower host reaction to the parasite lure was not due to chemical cues, but was elicited by the visual facial pattern of the parasite. Experimental manipulation of this visual pattern demonstrated that the black lower part of the clypeus of the parasite is the trait able to reduce host aggression. This pattern can be considered an honest signal since it visually amplifies the mandibular width, giving information about the parasite’s dangerousness. [Copyright &y& Elsevier]

Identifying broad-scale evolutionary processes that maintain phenotypic polymorphisms has been a major goal of modern evolutionary biology. There are numerous mechanisms, such as negative frequency-dependent selection, that may maintain polymorphisms, although it is unknown which mechanisms are prominent in nature. Traits used for individual recognition are strikingly variable and have evolved independently in numerous lineages, providing an excellent model to investigate which factors maintain ecologically relevant phenotypic polymorphisms. Theoretical models suggest that individuals may benefit by advertising their identities with distinctive, recognizable phenotypes. Here, we test the benefits of advertising one's identity with a distinctive phenotype. We manipulated the appearance of Polistes fuscatus paper wasp groups so that three individuals had the same appearance and one individual had a unique, easily recognizable appearance. We found that individuals with distinctive appearances received less aggression than individuals with nondistinctive appearances. Therefore, individuals benefit by advertising their identity with a unique phenotype. Our results provide a potential mechanism through which negative frequency-dependent selection may maintain the polymorphic identity signals in P. fuscatus. Given that recognition is important for many social interactions, selection for distinctive identity signals may be an underappreciated and widespread mechanism underlying the evolution of phenotypic polymorphisms in social taxa. [ABSTRACT FROM AUTHOR]

Foundresses and workers of Polistes paper wasps show slight morphological and physiological differences. However, after the emergence of the workers, the castes can be readily discriminated by their behaviour: the dominant foundress is the principal egg-layer, whereas workers perform different tasks linked to colony development. Previous studies have demonstrated in this genus that defence of the colony by the workers is more effectively carried out by a collective response elicited by venom volatiles used as alarm pheromones. In the present study, gas chromatography-mass spectrometry analyses of the venom volatiles of foundresses and workers of Polistes dominulus (Christ) show predominantly quantitative differences. Spiroacetals, mainly (E,E)-2,8-dimethyl-1,7-dioxaspiro[5.5]undecane, are significantly higher in the venom volatiles fraction of workers, whereas the amount of N-(3-methylbutyl)acetamide is almost double in foundresses. On the basis of the chemical results, behavioural assays were performed on fifteen field colonies to test the alarm response of the resident wasps to venom extracts from foundresses and workers. Our behavioural results suggest that worker venom has a stronger alarm effect on the colonies than that of the foundresses, which seems unable to elicit the complete alarm response ending with a final attack and sting. The venom volatiles of P. dominulus workers serve mainly to alarm the colony whilst those of foundresses may also be linked to additional functions related to conspecific interactions. [ABSTRACT FROM AUTHOR]

Using demography data for the primitively eusocial wasp Ropalidia fasciata collected at 10 survey stations over 5 years, the effects of foundress group size (FGS) on colony survival rate and production of progeny were examined. The distribution pattern for the frequency of nests established by different numbers of foundresses fit a 0-truncated negative binomial distribution. The rate of nest failure up to the beginning of June decreased with FGS, and colony survival rate up to June and September increased with FGS. Although there were large variations among stations and years, the survival rate of colonies established by a single foundress (haplometrotic colonies) was significantly lower than that of colonies established by two or more foundresses (pleometrotic colonies). The number of new adults that emerged per colony up to the end of July increased with FGS, but there was no significant correlation between number of new adults per foundress and FGS. The number of potential foundresses produced per colony tended to increase with FGS, but there was no significant difference among the values produced per foundress for the three FGS categories. The percentage parasitism by an ichneumon parasitoid, Arthula formosana, tended to be higher in colonies established by a small number of foundresses. The relation between FGS and the productivity of the new foundresses was not statistically significant, suggesting that independent founding may be a better strategy for future subordinate foundresses. However, the long colony life span (mean 100 days, maximum 240 days) as compared with the shorter life span of foundresses (40 or 50 days) may be a good condition for the coexistence of many egg-layers in a colony. [ABSTRACT FROM AUTHOR]

The ecological constraints model (ECM) was formulated to predict how different ecological factors affect cooperative-breeding vertebrates. Within these groups some individuals help raise nondescendent young because of constraints that limit their own reproduction (e.g. limited foods, reproductive opportunities and nesting sites). Despite similarities between cooperative-breeding vertebrates and facultatively social insects, few studies have explicitly and experimentally determined how the ECM applies to social insects. In this study, we examined the potential effects of predation, density and nest site limitation as well as differences in nest site quality on the alternative nesting tactics of the paper wasp Mischocyttarus mexicanus. Accurate field estimates of density were possible because multiple nests are initiated in isolated Sabal palmetto trees. Results from a 17-month census showed more solitary nesting when density was low and nest sites were plentiful. In addition, females appeared to prefer nests initiated on unoccupied east-facing fronds. We then examined the potential effect of density and nest site limitation in a field experiment by adding or removing fronds from S. palmetto and forcing all females to renest. The percentage of haplometrotic females decreased when fronds were removed (increased density treatment), increased when fronds were added (decreased density treatment), and showed a mixed response when frond number remained unchanged (control density treatment). Nest site limitation did not appear to affect renesting females: the percentage of available unoccupied fronds was not affected by treatment. Mischocyttarus mexicanus females responded primarily to their social environment within palm groves and to variation in nest site quality, instead of constraints that typically affect cooperative-breeding vertebrates. [Copyright &y& Elsevier]

We tested 14 pairs of microsatellite primers that had been developed for the genus Polistes to assess their applicability for determining genetic structure in a colony of the genus Parapolybia. At least one of the 14 Polistes primer sets was useful for Parapolybia indica, and the locus identified by this primer set was highly polymorphic. Using this primer set, we estimated the average relatedness among female nestmates of Parapolybia indica to be 0.82 ± 0.05 (mean ± SE), indicating that in this species single mating is normal, although some cases of multiple mating was found. [ABSTRACT FROM AUTHOR]

Nineteen species of the paper wasp genus Ropalidia are recorded from Vietnam, of which three are new records for Vietnam. A key to all of the species, distribution records and taxonomic remarks are given. New synonymies proposed are: Ropalidia bicolorata parvula van der Vecht, 1962, under R. bicolorata van der Vecht, 1962; R. hongkongensis juncta van der Vecht, 1941, under R. hongkongensis (de Saussure, 1854); Icaria jucunda Cameron, 1898, and R. marginata sundaica van der Vecht, 1941, under R. marginata (Lepeletier, 1836); R. rufocollaris atrata van der Vecht, 1941, under R. rufocollaris (Cameron, 1900); and R. stigma rufa van der Vecht, 1941 and R. stigma nigrolineata van der Vecht, 1962, under R. stigma (Smith, 1858). [ABSTRACT FROM AUTHOR]

The taxonomy of the Australian species of twoRopalidiaspecies groups, theR. stigmagroup andR. variegatagroup, is revised and their distribution patterns are discussed. Two species in theR. stigmagroup (R. darwiniandR. elegantula), and four species in theR. variegatagroup (R. flavinoda,R. gregaria,R. mutabilisandR. revolutionalis) are recognized in Australia, with a new synonymy ofR. mutabilis torresianaRichards, 1978, underR. gregaria(de Saussure, 1854).Icaria torridaSmith, 1863, from Seram Island is synonymized withR. unicolor(Smith, 1859). [ABSTRACT FROM AUTHOR]

Mating structure and genetic relatedness among gynes (potential reproductive females) of the paper waspPolistes snelleniwere investigated using DNA microsatellite markers. All colonies had one foundress inseminated by a single male, and no sign of inbreeding was detected. The mean genetic relatedness among gynes was 0.734 ± 0.028 (SE), which is not significantly different from the expected value of 0.75 for full sisters. [ABSTRACT FROM AUTHOR]

We conducted a series of demographic studies of the primitively eusocial waspRopalidia fasciatain Okinawa, a subtropical part of Japan, and found the following. The colony cycle of this wasp is annual, spanning from April to November or even December; this is longer than the colony cycles of other temperate polistine wasps so far reported. The survival rate of the marked foundresses was 40% to June, dropping to 1.4% by September. These survival rates are similar to other subtropical and tropical species. Most females that emerged in November were probably second generation adults (progeny of the original foundresses), which would participate in founding nests in the following spring. These facts indicate thatR. fasciatain Okinawa is at least partially bivoltine. Survival of a nest to September was 10–20%; however, because a failed nest is often rebuilt, survival of the colony to September was as high as 50%. The mean number of new foundresses produced per foundress was 7.5, and their overwintering survival was 16%. Hence, a single foundress produced, on average, 1.2 progeny foundresses to the following year. Density dependence was shown in the rate at which the progeny foundresses were produced. These results explain the remarkable stability of nest densities from year to year in the area. The above results reveal thatR. fasciatain Okinawa shares many demographic characteristics with other primitively eusocial wasps, particularly year-to-year stability of nest density and a long colony cycle. [ABSTRACT FROM AUTHOR]

Abstract Morphological differences between queens and workers in an Australian swarm-founding paper wasp, Ropalidia romandi , were examined, providing detailed information on the nature of morphological caste differences in swarm-founding Ropalidia for the first time. Queens and workers differed in overall size and had divergent shapes, but differences were not always significant. In colonies in which queen–worker dimorphism was distinct, while the head width of queens was nearly the same as that of workers, queens were significantly larger in measures on the metasoma than workers. Plotting of metasomal variables against the mesosomal length and analysis of covariance showed that queen–worker morphological differentiation in R. romandi cannot be explained by simple linear allometric growth, suggesting that the two castes diverge in their growth parameters in the preadult stage. The pattern of morphological caste difference varied among colonies or was colony specific; there was no clear correlation between caste differences and colony cycle progression. These results suggest that morphological caste differences in R. romandi are determined genetically or by interactions between genetic background and intrinsic factors and/or external conditions. [ABSTRACT FROM AUTHOR]

We developed 10 polymorphic microsatellite loci for the Japanese paper wasp Polistes rothneyi using the magnetic particle method. Eight of the 10 loci tested were highly polymorphic, having four to eight alleles in P. rothneyi with an expected heterozygosity of 0.60–0.75. They also appeared to be applicable to other related species such as Polistes jokahamae. These loci can be used to study parameters concerning genetic relatedness such as worker reproduction and kin structure. [ABSTRACT FROM AUTHOR]

Abstract: Cooperative breeding decreases the direct reproductive output of subordinate individuals, but cooperation can be evolutionarily favored when there are challenges or constraints to breeding independently. Environmental factors, including temperature, precipitation, latitude, high seasonality, and environmental harshness have been hypothesized to correlate with the presence of cooperative breeding. However, to test the relationship between cooperation and ecological constraints requires comparative data on the frequency and variation of cooperative breeding across differing environments, ideally replicated across multiple species. Paper wasps are primitively social species, forming colonies composed of reproductively active dominants and foraging subordinates. Adult female wasps, referred to as foundresses, initiate new colonies. Nests can be formed by a single solitary foundress (noncooperative) or by multiple foundress associations (cooperative). Cooperative behavior varies within and among species, making paper wasps species well suited to disentangling ecological correlates of variation in cooperative behavior. This data set reports the frequency and extent of cooperative nest founding for 87 paper wasp species. Data were assembled from more than 170 published sources, previously unpublished field observations, and photographs contributed by citizen scientists to online natural history repositories. The data set includes 25,872 nest observations and reports the cooperative behavioral decisions for 45,297 foundresses. Species names were updated to reflect modern taxonomic revisions. The type of substrate on which the nest was built is also included, when available. A smaller population‐level version of this data set found that the presence or absence of cooperative nesting in paper wasps was correlated with temperature stability and environmental harshness, but these variables did not predict the extent of cooperation within species. This expanded data set contains details about individual nests and further increases the power to address the relationship between the environment and the presence and extent of cooperative breeding. Beyond the ecological drivers of cooperation, these high‐resolution data will be useful for future studies examining the evolutionary consequences of variation in social behavior. This data set may be used for research or educational purposes provided that this data paper is cited. [ABSTRACT FROM AUTHOR]