Publications

how to know which food is good for you: bumblebees use taste to discriminate between different concentrations of food differing in nutrient content.	in view of the ongoing pollinator decline, the role of nutrition in bee health has received increasing attention. bees obtain fat, carbohydrates and protein from pollen and nectar. as both excessive and deficient amounts of these macronutrients are detrimental, bees would benefit from assessing food quality to guarantee an optimal nutrient supply. while bees can detect sucrose and use it to assess nectar quality, it is unknown whether they can assess the macronutrient content of pollen. previous ...	2015	26202778
unraveling the venom proteome of the bumblebee (bombus terrestris) by integrating a combinatorial peptide ligand library approach with ft-icr ms.	within the apidae, the largest family of bees with over 5600 described species, the honeybee is the sole species with a well studied venom proteome. so far, only little research has focused on bumblebee venom. recently, the genome sequence of the european large earth bumblebee (bombus terrestris) became available and this allowed the first in-depth proteomic analysis of its venom composition. we identified 57 compounds, with 52 of them never described in bumblebee venom. remarkably, 72% of the d ...	2015	26071081
reproductive workers show queenlike gene expression in an intermediately eusocial insect, the buff-tailed bumble bee bombus terrestris.	bumble bees represent a taxon with an intermediate level of eusociality within hymenoptera. the clear division of reproduction between a single founding queen and the largely sterile workers is characteristic for highly eusocial species, whereas the morphological similarity between the bumble bee queen and the workers is typical for more primitively eusocial hymenopterans. also, unlike other highly eusocial hymenopterans, division of labour among worker subcastes is plastic and not predetermined ...	2015	25913260
bees prefer foods containing neonicotinoid pesticides.	the impact of neonicotinoid insecticides on insect pollinators is highly controversial. sublethal concentrations alter the behaviour of social bees and reduce survival of entire colonies. however, critics argue that the reported negative effects only arise from neonicotinoid concentrations that are greater than those found in the nectar and pollen of pesticide-treated plants. furthermore, it has been suggested that bees could choose to forage on other available flowers and hence avoid or dilute ...	2015	25901684
chronic exposure to neonicotinoids increases neuronal vulnerability to mitochondrial dysfunction in the bumblebee (bombus terrestris).	the global decline in the abundance and diversity of insect pollinators could result from habitat loss, disease, and pesticide exposure. the contribution of the neonicotinoid insecticides (e.g., clothianidin and imidacloprid) to this decline is controversial, and key to understanding their risk is whether the astonishingly low levels found in the nectar and pollen of plants is sufficient to deliver neuroactive levels to their site of action: the bee brain. here we show that bumblebees (bombus te ...	2015	25634958
nutrient balancing of the adult worker bumblebee (bombus terrestris) depends on the dietary source of essential amino acids.	animals carefully regulate the amount of protein that they consume. the quantity of individual essential amino acids (eaas) obtained from dietary protein depends on the protein source, but how the proportion of eaas in the diet affects nutrient balancing has rarely been studied. recent research using the geometric framework for nutrition has revealed that forager honeybees who receive much of their dietary eaas from floral nectar and not from solid protein have relatively low requirements for di ...	2015	25617453
insect vision models under scrutiny: what bumblebees (bombus terrestris terrestris l.) can still tell us.	three contending models address the ability of bees to detect and discriminate colours: the colour opponent coding (coc) model, the colour hexagon (ch) model and the receptor noise-limited (rn) model, but few studies attempt to determine which model fits experimental data best. to assess whether the models provide an accurate description of bumblebee colour space, we trained bees to discriminate four colour pairs. the perceptual distance between the colours of each pair was similar according to ...	2015	25613579
bees use honest floral signals as indicators of reward when visiting flowers.	pollinators visit flowers for rewards and should therefore have a preference for floral signals that indicate reward status, so called 'honest signals'. we investigated honest signalling in brassica rapa l. and its relevance for the attraction of a generalised pollinator, the bumble bee bombus terrestris (l.). we found a positive association between reward amount (nectar sugar and pollen) and the floral scent compound phenylacetaldehyde. bumble bees developed a preference for phenylacetaldehyde ...	2015	25491788
lethal and sublethal effects of azadirachtin on the bumblebee bombus terrestris (hymenoptera: apidae).	azadirachtin is a biorational insecticide commonly reported as selective to a range of beneficial insects. nonetheless, only few studies have been carried out with pollinators, usually emphasizing the honeybee apis mellifera and neglecting other important pollinator species such as the bumblebee bombus terrestris. here, lethal and sublethal effects of azadirachtin were studied on b. terrestris via oral exposure in the laboratory to bring out the potential risks of the compound to this important ...	2015	25300506
host manipulation of bumble bee queens by sphaerularia nematodes indirectly affects foraging of non-host workers.	sphaerularia bombi dufour is a major parasite of bumble bee queens that manipulates its host's behavior: parasitized queens do not breed and found nests but continue to fly into the early summer months. we examined the indirect consequences of this host manipulation on non-host workers in central hokkaido island, japan. in this area, parasitism of bombus terrestris by s. bombi is common but does not affect every queen; therefore, as summer begins, b. terrestris queens continue to dominate some f ...	2015	26236849
bifidobacterium commune sp. nov. isolated from the bumble bee gut.	bifidobacteria were isolated from the gut of bombus lapidarius, bombus terrestris and bombus hypnorum bumble bees by direct isolation on modified trypticase phytone yeast extract agar. the maldi-tof ms profiles of four isolates (lmg 28292(t), r-53560, r-53124, lmg 28626) were found to be identical and did not cluster with the profiles of established bifidobacterium species. analysis of the 16s rrna gene sequence of strain lmg 28292(t) revealed that lmg 28292(t) is most closely related to the bif ...	2015	25753540
behavioural evidence for self-medication in bumblebees?	the presence of antimicrobial secondary metabolites in nectar suggests that pollinators, which are threatened globally by emergent disease, may benefit from the consumption of nectars rich in these metabolites. we tested whether nicotine, a nectar secondary metabolite common in solanaceae and tilia species, is used by parasitized bumblebees as a source of self-medication , using a series of toxicological, microbiological and behavioural experiments. caged bees infected with crithidia bombi had a ...	2015	25949807
bee pathogens found in bombus atratus from colombia: a case study.	bombus atratus bumblebees from colombia that were caught in the wild and from breeding programs were screened for a broad set of bee pathogens. we discovered for the first time lake sinai virus and confirmed the infection by other common viruses. the prevalence of apicystis bombi, crithidia bombi and nosema ceranae was remarkably high. according to other studies the former two could have been co-introduced in south america with exotic bumble bees as bombus terrestris or bombus ruderatus. given t ...	2015	26031564
molecular cloning and characterization of the allatotropin precursor and receptor in the desert locust, schistocerca gregaria.	allatotropins (ats) are pleiotropic neuropeptides initially isolated from the tobacco hornworm, manduca sexta. in 2008, the first receptor for at-like peptides (atr) was characterized in bombyx mori. since then, atrs have also been characterized in m. sexta, tribolium castaneum, aedes aegypti and bombus terrestris. these receptors show sequence similarity to vertebrate orexin (orx) receptors. when generating an est-database of the desert locust (schistocerca gregaria) central nervous system, we ...	2015	25814925
the genomes of two key bumblebee species with primitive eusocial organization.	the shift from solitary to social behavior is one of the major evolutionary transitions. primitively eusocial bumblebees are uniquely placed to illuminate the evolution of highly eusocial insect societies. bumblebees are also invaluable natural and agricultural pollinators, and there is widespread concern over recent population declines in some species. high-quality genomic data will inform key aspects of bumblebee biology, including susceptibility to implicated population viability threats.	2015	25908251
a depauperate immune repertoire precedes evolution of sociality in bees.	sociality has many rewards, but can also be dangerous, as high population density and low genetic diversity, common in social insects, is ideal for parasite transmission. despite this risk, honeybees and other sequenced social insects have far fewer canonical immune genes relative to solitary insects. social protection from infection, including behavioral responses, may explain this depauperate immune repertoire. here, based on full genome sequences, we describe the immune repertoire of two ecol ...	2015	25908406
the effect of oral administration of dsrna on viral replication and mortality in bombus terrestris.	israeli acute paralysis virus (iapv), a single-stranded rna virus, has a worldwide distribution and affects honeybees as well as other important pollinators. iapv infection in honeybees has been successfully repressed by exploiting the rna interference (rnai) pathway of the insect's innate immune response with virus-specific double stranded rna (dsrna). here we investigated the effect of iapv infection in the bumblebee bombus terrestris and its tissue tropism. b. terrestris is a common pollinato ...	2015	26110584
buckling failures in insect exoskeletons.	thin walled tubes are often used for load-bearing structures, in nature and in engineering, because they offer good resistance to bending and torsion at relatively low weight. however, when loaded in bending they are prone to failure by buckling. it is difficult to predict the loading conditions which cause buckling, especially for tubes whose cross sections are not simple shapes. insights into buckling prevention might be gained by studying this phenomenon in the exoskeletons of insects and oth ...	2015	26678374
a conserved class of queen pheromones? re-evaluating the evidence in bumblebees (bombus impatiens).	the regulation of reproductive division of labour is a key component in the evolution of social insects. chemical signals are important mechanisms to regulate worker reproduction, either as queen-produced pheromones that coercively inhibit worker reproduction or as queen signals that honestly advertise her fecundity. a recent study suggested that a conserved class of hydrocarbons serve as queen pheromones across three independent origins of eusociality. in bumblebees (bombus terrestris), pentaco ...	2015	26490791
characterisation of acetyl-coa thiolase: the first enzyme in the biosynthesis of terpenic sex pheromone components in the labial gland of bombus terrestris.	buff-tailed bumblebees, bombus terrestris, use a male sex pheromone for premating communication. its main component is a sesquiterpene, 2,3-dihydrofarnesol. this paper reports the isolation of a thiolase (acetyl-coa thiolase, aact_bt), the first enzyme involved in the biosynthetic pathway leading to formation of isoprenoids in the b. terrestris male sex pheromone. characterisation of aact_bt might contribute to a better understanding of pheromonogenesis in the labial gland of b. terrestris males ...	2015	25801592
neonicotinoids and bumblebees (bombus terrestris): effects on nectar consumption in individual workers.	the objective of this study was to quantify whether the presence of three different neonicotinoid insecticides (imidacloprid, thiamethoxam or clothianidin) in sucrose solution results in antifeedant effects in individual worker bumblebees (bombus terrestris), and, if so, whether this effect is reversible if bees are subsequently offered untreated feed.	2015	25132051
extracting the behaviorally relevant stimulus: unique neural representation of farnesol, a component of the recruitment pheromone of bombus terrestris.	to trigger innate behavior, sensory neural networks are pre-tuned to extract biologically relevant stimuli. many male-female or insect-plant interactions depend on this phenomenon. especially communication among individuals within social groups depends on innate behaviors. one example is the efficient recruitment of nest mates by successful bumblebee foragers. returning foragers release a recruitment pheromone in the nest while they perform a 'dance' behavior to activate unemployed nest mates. a ...	2015	26340263
production of reactive oxygen species by flight muscle mitochondria of the bumblebee (bombus terrestris l.).		2015	26335818
sensitive determination of mixtures of neonicotinoid and fungicide residues in pollen and single bumblebees using a scaled down quechers method for exposure assessment.	to accurately estimate exposure of bees to pesticides, analytical methods are needed to enable quantification of nanogram/gram (ng/g) levels of contaminants in small samples of pollen or the individual insects. a modified quechers extraction method coupled with ultra-high-performance liquid chromatography tandem mass spectrometry (uhplc-ms/ms) analysis was tested to quantify residues of 19 commonly used neonicotinoids and fungicides and the synergist, piperonyl butoxide, in 100 mg samples of pol ...	2015	26329280
the influence of prior learning experience on pollinator choice: an experiment using bumblebees on two wild floral types of antirrhinum majus.	understanding how pollinator behavior may influence pollen transmission across floral types is a major challenge, as pollinator decision depends on a complex range of environmental cues and prior experience. here we report an experiment using the plant antirrhinum majus and the bumblebee bombus terrestris to investigate how prior learning experience may affect pollinator preferences between floral types when these are presented together. we trained naive bumblebees to forage freely on flowering ...	2015	26263186
allele specific expression in worker reproduction genes in the bumblebee bombus terrestris.	methylation has previously been associated with allele specific expression in ants. recently, we found methylation is important in worker reproduction in the bumblebee bombus terrestris. here we searched for allele specific expression in twelve genes associated with worker reproduction in bees. we found allele specific expression in ecdysone 20 monooxygenase and imp-l2-like. although we were unable to confirm a genetic or epigenetic cause for this allele specific expression, the expression patte ...	2015	26213649
rearing and foraging affects bumblebee (bombus terrestris) gut microbiota.	bumblebees are ecologically and economically important as pollinators of crop and wild plants, especially in temperate systems. species, such as the buff-tailed bumblebee (bombus terrestris), are reared commercially to pollinate high-value crops. their highly specific gut microbiota, characterized by low diversity, may affect nutrition and immunity and are likely to be important for fitness and colony health. however, little is known about how environmental factors affect bacterial community str ...	2015	25994560
population genetic structure of bombus terrestris in europe: isolation and genetic differentiation of irish and british populations.	the genetic structure of the earth bumblebee (bombus terrestris l.) was examined across 22 wild populations and two commercially reared populations using eight microsatellite loci and two mitochondrial genes. our study included wild bumblebee samples from six populations in ireland, one from the isle of man, four from britain and 11 from mainland europe. a further sample was acquired from new zealand. observed levels of genetic variability and heterozygosity were low in ireland and the isle of m ...	2015	25958977
quantitative trait loci for light sensitivity, body weight, body size, and morphological eye parameters in the bumblebee, bombus terrestris.	bumblebees such as bombus terrestris are essential pollinators in natural and managed ecosystems. in addition, this species is intensively used in agriculture for its pollination services, for instance in tomato and pepper greenhouses. here we performed a quantitative trait loci (qtl) analysis on b. terrestris using 136 microsatellite dna markers to identify genes linked with 20 traits including light sensitivity, body size and mass, and eye and hind leg measures. by composite interval mapping ( ...	2015	25928544
16s rrna amplicon sequencing demonstrates that indoor-reared bumblebees (bombus terrestris) harbor a core subset of bacteria normally associated with the wild host.	a miseq multiplexed 16s rrna amplicon sequencing of the gut microbiota of wild and indoor-reared bombus terrestris (bumblebees) confirmed the presence of a core set of bacteria, which consisted of neisseriaceae (snodgrassella), orbaceae (gilliamella), lactobacillaceae (lactobacillus), and bifidobacteriaceae (bifidobacterium). in wild b. terrestris we detected several non-core bacteria having a more variable prevalence. although enterobacteriaceae are unreported by non next-generation sequencing ...	2015	25923917
the distribution of parasite strains among hosts affects disease spread in a social insect.	social insects present highly interesting and experimentally amenable systems for the study of disease transmission because they naturally live in dense groups of frequently interacting individuals. using experimental inoculations of five trypanosomatid strains into groups of its natural host, the bumblebee bombus terrestris, we investigate the effects of the initial parasite strain distribution across group members on the establishment and transmission success of the different strains to new ho ...	2015	25858120
effect of light intensity on flight control and temporal properties of photoreceptors in bumblebees.	to control flight, insects rely on the pattern of visual motion generated on the retina as they move through the environment. when light levels fall, vision becomes less reliable and flight control thus becomes more challenging. here, we investigated the effect of light intensity on flight control by filming the trajectories of free-flying bumblebees (bombus terrestris, linnaeus 1758) in an experimental tunnel at different light levels. as light levels fell, flight speed decreased and the flight ...	2015	25750416
merging of long-term memories in an insect.	research on comparative cognition has largely focused on successes and failures of animals to solve certain cognitive tasks, but in humans, memory errors can be more complex than simple failures to retrieve information [1, 2]. the existence of various types of "false memories," in which individuals remember events that they have never actually encountered, are now well established in humans [3, 4]. we hypothesize that such systematic memory errors may be widespread in animals whose natural lifes ...	2015	25728692
a comparison of techniques for assessing farmland bumblebee populations.	agri-environment schemes have been implemented across the european union in order to reverse declines in farmland biodiversity. to assess the impact of these schemes for bumblebees, accurate measures of their populations are required. here, we compared bumblebee population estimates on 16 farms using three commonly used techniques: standardised line transects, coloured pan traps and molecular estimates of nest abundance. there was no significant correlation between the estimates obtained by the ...	2015	25676106
bumblebees measure optic flow for position and speed control flexibly within the frontal visual field.	when flying through narrow spaces, insects control their position by balancing the magnitude of apparent image motion (optic flow) experienced in each eye and their speed by holding this value about a desired set point. previously, it has been shown that when bumblebees encounter sudden changes in the proximity to nearby surfaces - as indicated by a change in the magnitude of optic flow on each side of the visual field - they adjust their flight speed well before the change, suggesting that they ...	2015	25657205
new insights of side-effects of tau-fluvalinate on biological agents and pollinators.	a high number of side-effects trials were developed and carried out on beneficial insects and mites by the 'side-effects on beneficial organisms' iobc working group and subsequently published in the iobc bulletins over a number of years. in general, these tests were mainly carried out under laboratory and/or semi-field conditions following the very worst case scenario applications, leading to an iobc classification of 3 (moderately toxic) and 4 (harmful) for many of the tested compounds however, ...	2015	27145571
comparative flight morphology in queens of invasive and native patagonian bumblebees (hymenoptera: bombus).	since its introduction in chile, the european bombus terrestris l. (hymenoptera: apidae) has progressively reduced the abundance of the native patagonian bumblebee, bombus dahlbomii guérin. because an important cause of successful invasion of a species may depend on a potentially advantageous phenotype, we studied morphologies related to flight performance (flight muscle ratio (fmr), wing loading (wl), excess power index (epi, which integrates fmr and wl) and wing aspect ratio (ar)) in the queen ...	2015	25499798
correction: extracting the behaviorally relevant stimulus: unique neural representation of farnesol, a component of the recruitment pheromone of bombus terrestris.		2015	26407079
bumblebee homing: the fine structure of head turning movements.	changes in flight direction in flying insects are largely due to roll, yaw and pitch rotations of their body. head orientation is stabilized for most of the time by counter rotation. here, we use high-speed video to analyse head- and body-movements of the bumblebee bombus terrestris while approaching and departing from a food source located between three landmarks in an indoor flight-arena. the flight paths consist of almost straight flight segments that are interspersed with rapid turns. these ...	2015	26352836
modality-specific attention in foraging bumblebees.	attentional demands can prevent humans and other animals from performing multiple tasks simultaneously. some studies, however, show that tasks presented in different sensory modalities (e.g. visual and auditory) can be processed simultaneously. this suggests that, at least in these cases, attention might be modality-specific and divided differently between tasks when present in the same modality compared with different modalities. we investigated this possibility in bumblebees (bombus terrestris ...	2015	26587245
seasonal dynamics in the chemistry and structure of the fat bodies of bumblebee queens.	insects' fat bodies are responsible for nutrient storage and for a significant part of intermediary metabolism. thus, it can be expected that the structure and content of the fat body will adaptively change, if an insect is going through different life stages. bumblebee queens belong to such insects as they dramatically change their physiology several times over their lives in relation to their solitary overwintering, independent colony foundation stage, and during the colony life-cycle ending i ...	2015	26559946
monitoring the effects of thiamethoxam applied as a seed treatment to winter oilseed rape on the development of bumblebee (bombus terrestris) colonies.	the development of bumblebee (bombus terrestris audax) colonies that had foraged for 5 weeks on flowering winter oilseed rape grown from seed treated with thiamethoxam (as cruiser osr) was assessed (two control, one treated field). colony development was evaluated by monitoring the colony mass, forager activity was assessed, both at the hive and within the crop, and the contribution of oilseed rape to the pollen stored within the colony was analysed.	2016	26685925
bumblebee flight performance in environments of different proximity.	flying animals are capable of navigating through environments of different complexity with high precision. to control their flight when negotiating narrow tunnels, bees and birds use the magnitude of apparent image motion (known as optic flow) generated by the walls. in their natural habitat, however, these animals would encounter both cluttered and open environments. here, we investigate how large changes in the proximity of nearby surfaces affect optic flow-based flight control strategies. we ...	2016	26614094
ozone degrades floral scent and reduces pollinator attraction to flowers.	in this work we analyzed the degradation of floral scent volatiles from brassica nigra by reaction with ozone along a distance gradient and the consequences for pollinator attraction. for this purpose we used a reaction system comprising three reaction tubes in which we conducted measurements of floral volatiles using a proton-transfer-reaction time-of-flight mass spectrometer (ptr-tof-ms) and gc-ms. we also tested the effects of floral scent degradation on the responses of the generalist pollin ...	2016	26346807
complete mitochondrial genome of bombus terrestris (hymenoptera: apidae).	in this study, complete mitochondrial genome of the large earth bumblebee, bombus terrestris, was first determined. the mitochondrial genome is 174 000 bp in length, and encodes 1 d-loop region, 2 ribosomal rna genes, 13 protein-coding genes and 20 transfer rna genes. average gc content of this genome is 15%. nad6 and cob are overlapped with 12 bp, while atp8 and atp6 are overlapped with 18 bp. phylogeny analysis indicates bombus species exhibit closer genetic distance with melipona species than ...	2016	26437124
a low-cost, computer-controlled robotic flower system for behavioral experiments.	human observations during behavioral studies are expensive, time-consuming, and error prone. for this reason, automatization of experiments is highly desirable, as it reduces the risk of human errors and workload. the robotic system we developed is simple and cheap to build and handles feeding and data collection automatically. the system was built using mostly off-the-shelf components and has a novel feeding mechanism that uses servos to perform refill operations. we used the robotic system in ...	2016	27066245
insect pollination reduces yield loss following heat stress in faba bean (vicia faba l.).	global food security, particularly crop fertilization and yield production, is threatened by heat waves that are projected to increase in frequency and magnitude with climate change. effects of heat stress on the fertilization of insect-pollinated plants are not well understood, but experiments conducted primarily in self-pollinated crops, such as wheat, show that transfer of fertile pollen may recover yield following stress. we hypothesized that in the partially pollinator-dependent crop, faba ...	2016	26989276
monitoring flower visitation networks and interactions between pairs of bumble bees in a large outdoor flight cage.	pollinators, such as bees, often develop multi-location routes (traplines) to exploit subsets of flower patches within larger plant populations. how individuals establish such foraging areas in the presence of other foragers is poorly explored. here we investigated the foraging patterns of pairs of bumble bees (bombus terrestris) released sequentially into an 880m2 outdoor flight cage containing 10 feeding stations (artificial flowers). using motion-sensitive video cameras mounted on flowers, we ...	2016	26982030
exploring complex pheromone biosynthetic processes in the bumblebee male labial gland by rna sequencing.	male marking pheromones (mps) are used by the majority of bumblebee species (hymenoptera: apidae), including a commercially important greenhouse pollinator, the buff-tailed bumblebee (bombus terrestris), to attract conspecific females. mp biosynthetic processes in the cephalic part of the bumblebee male labial gland (lg) are of extraordinary complexity, involving enzymes of fatty acid and isoprenoid biosynthesis, which jointly produce more than 50 compounds. we employed a differential transcript ...	2016	26945888
flower iridescence increases object detection in the insect visual system without compromising object identity.	iridescence is a form of structural coloration, produced by a range of structures, in which hue is dependent on viewing angle [1-4]. one of these structures, the diffraction grating, is found both in animals (for example, beetles [2]) and in plants (on the petals of some animal pollinated flowers [5]). the behavioral impacts of floral iridescence and its potential ecological significance are unknown [6-9]. animal-pollinated flowers are described as "sensory billboards" [10], with many floral fea ...	2016	26923789
nest wax triggers worker reproduction in the bumblebee bombus terrestris.	social insects are well known for their high level of cooperation. workers of the primitively eusocial bumblebee bombus terrestris are able to produce male offspring in the presence of a queen. nonetheless, they only compete for reproduction, in the so-called competition phase, when the workforce is large enough to support the rearing of reproductives. so far, little is known about the proximate mechanisms underlying the shift between altruism and selfish behaviour in bumblebee workers. in this ...	2016	26909189
exploring miniature insect brains using micro-ct scanning techniques.	the capacity to explore soft tissue structures in detail is important in understanding animal physiology and how this determines features such as movement, behaviour and the impact of trauma on regular function. here we use advances in micro-computed tomography (micro-ct) technology to explore the brain of an important insect pollinator and model organism, the bumblebee (bombus terrestris). here we present a method for accurate imaging and exploration of insect brains that keeps brain tissue fre ...	2016	26908205
worldwide alien invasion: a methodological approach to forecast the potential spread of a highly invasive pollinator.	the ecological impacts of alien species invasion are a major threat to global biodiversity. the increasing number of invasion events by alien species and the high cost and difficulty of eradicating invasive species once established require the development of new methods and tools for predicting the most susceptible areas to invasion. invasive pollinators pose serious threats to biodiversity and human activity due to their close relationship with many plants (including crop species) and high pote ...	2016	26882479
male bumblebees, bombus terrestris, perform equally well as workers in a serial colour-learning task.	the learning capacities of males and females may differ with sex-specific behavioural requirements. bumblebees provide a useful model system to explore how different lifestyles are reflected in learning abilities, because their (female but sterile) workers and males engage in fundamentally different behaviour routines. bumblebee males, like workers, embark on active flower foraging but in contrast to workers they have to trade off their feeding with mate search, potentially affecting their abili ...	2016	26877542
the final moments of landing in bumblebees, bombus terrestris.	in comparison to other insects, like honeybees, bumblebees are very effective pollinators. even though landing is a crucial part of pollination, little is known about how bumblebees orchestrate the final, critical moments of landing. here, we use high-speed recordings to capture the fine details of the landing behaviour of free-flying bumblebees (bombus terrestris), while landing on a flat platform with different orientations. we find that the bees have a fairly constant body and head orientatio ...	2016	26868924
regulation of isoprenoid pheromone biosynthesis in bumblebee males.	males of the closely related species bombus terrestris and bombus lucorum attract conspecific females by completely different marking pheromones. mp of b. terrestris and b. lucorum pheromones contain mainly isoprenoid (isp) compounds and fatty acid derivatives, respectively. here, we studied the regulation of isp biosynthesis in both bumblebees. rna-seq and qrt-pcr analyses indicated that acetoacetyl-coa thiolase (aact), 3-hydroxy-3-methylglutaryl-coa reductase (hmgr), and farnesyl diphosphate s ...	2016	26632352
gene expression dynamics in major endocrine regulatory pathways along the transition from solitary to social life in a bumblebee, bombus terrestris.	understanding the social evolution leading to insect eusociality requires, among other, a detailed insight into endocrine regulatory mechanisms that have been co-opted from solitary ancestors to play new roles in the complex life histories of eusocial species. bumblebees represent well-suited models of a relatively primitive social organization standing on the mid-way to highly advanced eusociality and their queens undergo both, a solitary and a social phase, separated by winter diapause. in the ...	2016	27932998
specialization on pollen or nectar in bumblebee foragers is not associated with ovary size, lipid reserves or sensory tuning.	foraging specialization allows social insects to more efficiently exploit resources in their environment. recent research on honeybees suggests that specialization on pollen or nectar among foragers is linked to reproductive physiology and sensory tuning (the reproductive ground-plan hypothesis; rgph). however, our understanding of the underlying physiological relationships in non-apis bees is still limited. here we show that the bumblebee bombus terrestris has specialist pollen and nectar forag ...	2016	27812411
bumblebees perform well-controlled landings in dim light.	to make a smooth touchdown when landing, an insect must be able to reliably control its approach speed as well as its body and leg position-behaviors that are thought to be regulated primarily by visual information. bumblebees forage and land under a broad range of light intensities and while their behavior during the final moments of landing has been described in detail in bright light, little is known about how this is affected by decreasing light intensity. here, we investigate this by charac ...	2016	27683546
no effect of juvenile hormone on task performance in a bumblebee (bombus terrestris) supports an evolutionary link between endocrine signaling and social complexity.	a hallmark of insect societies is a division of labor among workers specializing in different tasks. in bumblebees the division of labor is related to body size; relatively small workers are more likely to stay inside the nest and tend ("nurse") brood, whereas their larger sisters are more likely to forage. despite their ecological and economic importance, very little is known about the endocrine regulation of division of labor in bumblebees. we studied the influence of juvenile hormone (jh) on ...	2016	27503109
signatures of a globally optimal searching strategy in the three-dimensional foraging flights of bumblebees.	simulated annealing is a powerful stochastic search algorithm for locating a global maximum that is hidden among many poorer local maxima in a search space. it is frequently implemented in computers working on complex optimization problems but until now has not been directly observed in nature as a searching strategy adopted by foraging animals. we analysed high-speed video recordings of the three-dimensional searching flights of bumblebees (bombus terrestris) made in the presence of large or sm ...	2016	27459948
structural analysis of hand drawn bumblebee bombus terrestris silk.	bombus terrestris, commonly known as the buff-tailed bumblebee, is native to europe, parts of africa and asia. it is commercially bred for use as a pollinator of greenhouse crops. larvae pupate within a silken cocoon that they construct from proteins produced in modified salivary glands. the amino acid composition and protein structure of hand drawn b. terrestris, silk fibres was investigated through the use of micro-raman spectroscopy. spectra were obtained from single fibres drawn from the lar ...	2016	27447623
mechanosensory hairs in bumblebees (bombus terrestris) detect weak electric fields.	bumblebees (bombus terrestris) use information from surrounding electric fields to make foraging decisions. electroreception in air, a nonconductive medium, is a recently discovered sensory capacity of insects, yet the sensory mechanisms remain elusive. here, we investigate two putative electric field sensors: antennae and mechanosensory hairs. examining their mechanical and neural response, we show that electric fields cause deflections in both antennae and hairs. hairs respond with a greater m ...	2016	27247399
israeli acute paralysis virus infection leads to an enhanced rna interference response and not its suppression in the bumblebee bombus terrestris.	rna interference (rnai) is the primary antiviral defense system in insects and its importance for pollinator health is indisputable. in this work, we examined the effect of israeli acute paralysis virus (iapv) infection on the rnai process in the bumblebee, bombus terrestris, and whether the presence of possible functional viral suppressors could alter the potency of the host's immune response. for this, a two-fold approach was used. through a functional rnai assay, we observed an enhancement of ...	2016	27999371
differential expression pattern of vago in bumblebee (bombus terrestris), induced by virulent and avirulent virus infections.	viruses are one of the main drivers of the decline of domesticated and wild bees but the mechanisms of antiviral immunity in pollinators are poorly understood. recent work has suggested that next to the small interfering rna (sirna) pathway other immune-related pathways play a role in the defense of the bee hosts against viral infection. in addition, vago plays a role in the cross-talk between the innate immune pathways in culex mosquito cells. here we describe the vago orthologue in bumblebees ...	2016	27680717
unbiased rna shotgun metagenomics in social and solitary wild bees detects associations with eukaryote parasites and new viruses.	the diversity of eukaryote organisms and viruses associated with wild bees remains poorly characterized in contrast to the well-documented pathosphere of the western honey bee, apis mellifera. using a deliberate rna shotgun metagenomic sequencing strategy in combination with a dedicated bioinformatics workflow, we identified the (micro-)organisms and viruses associated with two bumble bee hosts, bombus terrestris and bombus pascuorum, and two solitary bee hosts, osmia cornuta and andrena vaga. i ...	2016	28006002
the effects of single and mixed infections of apicystis bombi and deformed wing virus in bombus terrestris.	many pollinators are currently suffering from declines, diminishing their gene pool and increasing their vulnerability to parasites. recently, an increasing diversity of parasites has been recorded in bumblebees, yet for many, knowledge of their virulence and hence the risk their presence poses, is lacking. the deformed wing virus (dwv), known to be ubiquitous in honey bees, has now been detected in bumblebees. in addition, the neogregarine apicystis bombi has been discovered to be more prevalen ...	2016	26646676
reliability of the entomovector technology using prestop-mix and bombus terrestris l. as a fungal disease biocontrol method in open field.	botrytis cinerea pers.:fr. is a major plant pathogen, and a new approach is needed for its control in strawberry to minimise the increasing use of synthetic fungicides. the biofungicide prestop-mix, which contains gliocladium catenulatum, is effective against botrytis infections; however, the need for frequent applications increases the costs for farmers. here, we demonstrate that bumble bees, bombus terrestris l., effectively disseminate the preparation onto flowers in open field conditions. ov ...	2016	27530075
immune response and gut microbial community structure in bumblebees after microbiota transplants.	microbial communities are a key component of host health. as the microbiota is initially 'foreign' to a host, the host's immune system should respond to its acquisition. such variation in the response should relate not only to host genetic background, but also to differences in the beneficial properties of the microbiota. however, little is known about such interactions. here, we investigate the gut microbiota of the bumblebee, bombus terrestris, which has a protective function against the bee's ...	2016	27226466
insect antimicrobial peptides act synergistically to inhibit a trypanosome parasite.	the innate immune system provides protection from infection by producing essential effector molecules, such as antimicrobial peptides (amps) that possess broad-spectrum activity. this is also the case for bumblebees, bombus terrestris, when infected by the trypanosome, crithidia bombi furthermore, the expressed mixture of amps varies with host genetic background and infecting parasite strain (genotype). here, we used the fact that clones of c. bombi can be cultivated and kept as strains in mediu ...	2016	27160603
colony pace: a life-history trait affecting social insect epidemiology.	among colonies of social insects, the worker turnover rate (colony 'pace') typically shows considerable variation. this has epidemiological consequences for parasites, because in 'fast-paced' colonies, with short-lived workers, the time of parasite residence in a given host will be reduced, and further transmission may thus get less likely. here, we test this idea and ask whether pace is a life-history strategy against infectious parasites. we infected bumblebees (bombus terrestris) with the inf ...	2016	26763696
growth rate of bumblebee larvae is related to pollen amino acids.	the use of bombus terrestris l. commercial colonies for outdoor and greenhouse crop pollination is currently widespread. colony breeding includes bumblebee feeding, mostly by using the honeybee pollen loads of diverse palynological composition. because the chemical content of pollen is highly variable, the choice of commercial blend should not be random but has to be carefully selected to ensure the optimal development of workers and then pollination efficacy. in this work, we compared the impac ...	2016	26385047
chronic neonicotinoid pesticide exposure and parasite stress differentially affects learning in honeybees and bumblebees.	learning and memory are crucial functions which enable insect pollinators to efficiently locate and extract floral rewards. exposure to pesticides or infection by parasites may cause subtle but ecologically important changes in cognitive functions of pollinators. the potential interactive effects of these stressors on learning and memory have not yet been explored. furthermore, sensitivity to stressors may differ between species, but few studies have compared responses in different species. here ...	2016	27053744
no effect of low-level chronic neonicotinoid exposure on bumblebee learning and fecundity.	in recent years, many pollinators have declined in abundance and diversity worldwide, presenting a potential threat to agricultural productivity, biodiversity and the functioning of natural ecosystems. one of the most debated factors proposed to be contributing to pollinator declines is exposure to pesticides, particularly neonicotinoids, a widely used class of systemic insecticide. also, newly emerging parasites and diseases, thought to be spread via contact with managed honeybees, may pose thr ...	2016	27014515
virus infection of plants alters pollinator preference: a payback for susceptible hosts?	plant volatiles play important roles in attraction of certain pollinators and in host location by herbivorous insects. virus infection induces changes in plant volatile emission profiles, and this can make plants more attractive to insect herbivores, such as aphids, that act as viral vectors. however, it is unknown if virus-induced alterations in volatile production affect plant-pollinator interactions. we found that volatiles emitted by cucumber mosaic virus (cmv)-infected tomato (solanum lycop ...	2016	27513727
review of field and monitoring studies investigating the role of nitro-substituted neonicotinoid insecticides in the reported losses of honey bee colonies (apis mellifera).	the nitro-substituted neonicotinoid insecticides, which include imidacloprid, thiamethoxam and clothianidin, are widely used to control a range of important agricultural pests both by foliar applications and also as seed dressings and by soil application. since they exhibit systemic properties, exposure of bees may occur as a result of residues present in the nectar and/or pollen of seed- or soil-treated crop plants and so they have been the subject of much debate about whether they cause advers ...	2016	27709399
large-scale monitoring of effects of clothianidin dressed oilseed rape seeds on pollinating insects in northern germany: implementation of the monitoring project and its representativeness.	monitoring studies at the landscape level are complex, expensive and difficult to conduct. many aspects have to be considered to avoid confounding effects which is probably the reason why they are not regularly performed in the context of risk assessments of plant protection products to pollinating insects. however, if conducted appropriately their contribution is most valuable. in this paper we identify the requirements of a large-scale monitoring study for the assessment of side-effects of clo ...	2016	27678527
large-scale monitoring of effects of clothianidin-dressed osr seeds on pollinating insects in northern germany: effects on large earth bumble bees (bombus terrestris).	the aim of this study was to investigate the effects of elado(®)-dressed winter oilseed rape (osr, 10 g clothianidin & 2 g beta-cyfluthrin/kg seed) on the development, reproduction and behaviour of large earth bumble bees (bombus terrestris) as part of a large-scale monitoring field study in northern germany, where osr is usually cultivated at 25-33 % of the arable land. both reference and test sites comprised 65 km(2) in which no other crops attractive to pollinating insects were present. six s ...	2016	27678526
bumble bees regulate their intake of essential protein and lipid pollen macronutrients.	bee population declines are linked to the reduction of nutritional resources due to land-use intensification, yet we know little about the specific nutritional needs of many bee species. pollen provides bees with their primary source of protein and lipids, but nutritional quality varies widely among host-plant species. therefore, bees might have adapted to assess resource quality and adjust their foraging behavior to balance nutrition from multiple food sources. we tested the ability of two bumb ...	2016	27742891
is non-host pollen suitable for generalist bumblebees?	current evidence suggests that pollen is both chemically and structurally protected. despite increasing interest in studying bee-flower networks, the constraints for bee development related to pollen nutritional content, toxicity and digestibility as well as their role in the shaping of bee-flower interactions have been poorly studied. in this study we combined bioassays of the generalist bee bombus terrestris on pollen of cirsium, trifolium, salix, and cistus genera with an assessment of nutrit ...	2016	27731933
interspecific sensitivity of bees towards dimethoate and implications for environmental risk assessment.	wild and domesticated bee species are exposed to a variety of pesticides which may drive pollinator decline. due to wild bee sensitivity data shortage, it is unclear if the honey bee apis mellifera is a suitable surrogate species in the current eu risk assessment scheme. furthermore, the underlying causes for sensitivity differences in bees are not established. we assessed the acute toxicity (median lethal dose, ld50) of dimethoate towards multiple bee species, generated a species sensitivity di ...	2016	27686060
synergistic mortality between a neonicotinoid insecticide and an ergosterol-biosynthesis-inhibiting fungicide in three bee species.	neonicotinoid insecticides have been identified as an important factor contributing to bee diversity declines. nonetheless, uncertainties remain about their impact under field conditions. most studies have been conducted on apis mellifera and tested single compounds. however, in agricultural environments, bees are often exposed to multiple pesticides. we explore the synergistic mortality between a neonicotinoid (clothianidin) and an ergosterol-biosynthesis-inhibiting fungicide (propiconazole) in ...	2016	27685544
chronic exposure to a neonicotinoid pesticide alters the interactions between bumblebees and wild plants.	insect pollinators are essential for both the production of a large proportion of world crops and the health of natural ecosystems. as important pollinators, bumblebees must learn to forage on flowers to feed both themselves and provision their colonies.increased use of pesticides has caused concern over sublethal effects on bees, such as impacts on reproduction or learning ability. however, little is known about how sublethal exposure to field-realistic levels of pesticide might affect the abil ...	2016	27512241
a novel behavioral assay to investigate gustatory responses of individual, freely-moving bumble bees (bombus terrestris).	generalist pollinators like the buff-tailed bumble bee, bombus terrestris, encounter both nutrients and toxins in the floral nectar they collect from flowering plants. only a few studies have described the gustatory responses of bees toward toxins in food, and these experiments have mainly used the proboscis extension response on restrained honey bees. here, a new behavioral assay is presented for measuring the feeding responses of freely-moving, individual worker bumble bees to nutrients and to ...	2016	27500630
life-long radar tracking of bumblebees.	insect pollinators such as bumblebees play a vital role in many ecosystems, so it is important to understand their foraging movements on a landscape scale. we used harmonic radar to record the natural foraging behaviour of bombus terrestris audax workers over their entire foraging career. every flight ever made outside the nest by four foragers was recorded. our data reveal where the bees flew and how their behaviour changed with experience, at an unprecedented level of detail. we identified how ...	2016	27490662
effects of habitat composition and landscape structure on worker foraging distances of five bumble bee species.	bumble bees (bombus spp.) are important pollinators of both crops and wildflowers. their contribution to this essential ecosystem service has been threatened over recent decades by changes in land use, which have led to declines in their populations. in order to design effective conservation measures, it is important to understand the effects of variation in landscape composition and structure on the foraging activities of worker bumble bees. this is because the viability of individual colonies ...	2016	27411246
israeli acute paralysis virus associated paralysis symptoms, viral tissue distribution and dicer-2 induction in bumblebee workers (bombus terrestris).	although it is known that israeli acute paralysis virus (iapv) can cause bee mortality, the symptoms of paralysis and the distribution of the virus in different body tissues and their potential to respond with an increase of the sirna antiviral immune system have not been studied. in this project we worked with bombus terrestris, which is one of the most numerous bumblebee species in europe and an important pollinator for wild flowers and many crops in agriculture. besides the classic symptoms o ...	2016	27230225
brevibacillus laterosporus inside the insect body: beneficial resident or pathogenic outsider?	brevibacillus laterosporus is an entomopathogenic bacterium showing varying degrees of virulence against diverse insect pests. conversely, it is regarded as a beneficial component of the intestinal flora in different animals and in some insect species including the honeybee. b. laterosporus was detected through a species-specific pcr assay in the body of different insects, including apis mellifera and bombus terrestris. a strain isolated from a honeybee worker was pathogenic to the house fly mus ...	2016	27180901
chemical reproductive traits of diploid bombus terrestris males: consequences on bumblebee conservation.	the current bumblebee decline leads to inbreeding in populations that fosters a loss of allelic diversity and diploid male production. as diploid males are viable and their offspring are sterile, bumblebee populations can quickly fall in a vortex of extinction. in this paper, we investigate for the first time a potential pre-mating mechanism through a major chemical reproductive trait (male cephalic labial gland secretions) that could prevent monandrous virgin queens from mating with diploid mal ...	2016	26953256
spatial vision in bombus terrestris.	bombus terrestris is one of the most commonly used insect models to investigate visually guided behavior and spatial vision in particular. two fundamental measures of spatial vision are spatial resolution and contrast sensitivity. in this study, we report the threshold of spatial resolution in b. terrestris and characterize the contrast sensitivity function of the bumblebee visual system for a dual choice discrimination task. we trained bumblebees in a y-maze experimental set-up to associate a v ...	2016	26912998
gene expression differences in relation to age and social environment in queen and worker bumble bees.	eusocial insects provide special insights into the genetic pathways influencing aging because of their long-lived queens and flexible aging schedules. using qrt-pcr in the primitively eusocial bumble bee bombus terrestris (linnaeus), we investigated expression levels of four candidate genes associated with taxonomically widespread age-related pathways (coenzyme q biosynthesis protein 7, coq7; dna methyltransferase 3, dnmt3; foraging, for; and vitellogenin, vg). in experiment 1, we tested how exp ...	2016	26883339
queen pheromones modulate dna methyltransferase activity in bee and ant workers.	dna methylation is emerging as an important regulator of polyphenism in the social insects. research has concentrated on differences in methylation between queens and workers, though we hypothesized that methylation is involved in mediating other flexible phenotypes, including pheromone-dependent changes in worker behaviour and physiology. here, we find that exposure to queen pheromone affects the expression of two dna methyltransferase genes in apis mellifera honeybees and in two species of las ...	2016	26814223
in vivo study of dicer-2-mediated immune response of the small interfering rna pathway upon systemic infections of virulent and avirulent viruses in bombus terrestris.	recent studies suggest a potent role of the small interfering rna (sirna) pathway in the control of bee viruses and its usefulness to tackle these viral diseases. however, the involvement of the sirna pathway in the defense against different bee viruses is still poorly understood. therefore, in this report, we comprehensively analyzed the response of the sirna pathway in bumblebees of bombus terrestris to systemic infections of the virulent israeli acute paralysis virus (iapv) and the avirulent ...	2016	26711439
effect of acute pesticide exposure on bee spatial working memory using an analogue of the radial-arm maze.	pesticides, including neonicotinoids, typically target pest insects by being neurotoxic. inadvertent exposure to foraging insect pollinators is usually sub-lethal, but may affect cognition. one cognitive trait, spatial working memory, may be important in avoiding previously-visited flowers and other spatial tasks such as navigation. to test this, we investigated the effect of acute thiamethoxam exposure on spatial working memory in the bumblebee bombus terrestris, using an adaptation of the radi ...	2016	27958350
herbivore-induced dna demethylation changes floral signalling and attractiveness to pollinators in brassica rapa.	plants have to fine-tune their signals to optimise the trade-off between herbivore deterrence and pollinator attraction. an important mechanism in mediating plant-insect interactions is the regulation of gene expression via dna methylation. however, the effect of herbivore-induced dna methylation changes on pollinator-relevant plant signalling has not been systematically investigated. here, we assessed the impact of foliar herbivory on dna methylation and floral traits in the model crop plant br ...	2016	27870873
investigating the impacts of field-realistic exposure to a neonicotinoid pesticide on bumblebee foraging, homing ability and colony growth.	the ability to forage and return home is essential to the success of bees as both foragers and pollinators. pesticide exposure may cause behavioural changes that interfere with these processes, with consequences for colony persistence and delivery of pollination services.we investigated the impact of chronic exposure (5-43 days) to field-realistic levels of a neonicotinoid insecticide (2·4 ppb thiamethoxam) on foraging ability, homing success and colony size using radio frequency identification ...	2016	27867216
[characteristics of functioning of succinate dehydrogenase from flight muscles of the bumblebee bombus terrestris (l.)].	it was found that the succinate oxidation rate in mitochondria of flight muscles of bombus terrestris l. in- creased by a factor of 2.15 after flying for 1 h. an electrophoretically homogenous preparation of succinate dehydrogenase with a specific activity of 7.14 u/mg protein and 81.55-fold purity was isolated from b. terrestris flight muscles. it is shown that this enzyme is represented in the muscle tissue by only one isoform with r,f = 0.24. the molecular weight of the native molecule and it ...	2016	25510105
comparative toxicity of pesticides and environmental contaminants in bees: are honey bees a useful proxy for wild bee species?	threats to wild and managed insect pollinators in europe are cause for both ecological and socio-economic concern. multiple anthropogenic pressures may be exacerbating pollinator declines. one key pressure is exposure to chemicals including pesticides and other contaminants. historically the honey bee (apis mellifera spp.) has been used as an 'indicator' species for 'standard' ecotoxicological testing but it has been suggested that it is not always a good proxy for other types of eusocial and so ...	2017	27847190
infections of virulent and avirulent viruses differentially influenced the expression of dicer-1, ago-1, and micrornas in bombus terrestris.	the microrna (mirna) pathway is well established to be involved in host-pathogen interactions. as key insect pollinators, bees are suffering from widely spreading viruses, especially honeybees and bumblebees. in order to better understand bee-virus interaction, we comparatively analyzed the involvement of the bumblebee mirna pathway upon infection by two different viruses. in our setup, an avirulent infection is induced by slow bee paralysis virus (sbpv) and a virulent infection is induced by is ...	2017	28374846
micrornas associated with caste determination and differentiation in a primitively eusocial insect.	in eusocial hymenoptera (ants, bees and wasps), queen and worker adult castes typically arise via environmental influences. a fundamental challenge is to understand how a single genome can thereby produce alternative phenotypes. a powerful approach is to compare the molecular basis of caste determination and differentiation along the evolutionary trajectory between primitively and advanced eusocial species, which have, respectively, relatively undifferentiated and strongly differentiated adult c ...	2017	28361900