| visual motion-sensitive neurons in the bumblebee brain convey information about landmarks during a navigational task. | bees use visual memories to find the spatial location of previously learnt food sites. characteristic learning flights help acquiring these memories at newly discovered foraging locations where landmarks-salient objects in the vicinity of the goal location-can play an important role in guiding the animal's homing behavior. although behavioral experiments have shown that bees can use a variety of visual cues to distinguish objects as landmarks, the question of how landmark features are encoded by ... | 2014 | 25309374 |
| bumblebee size polymorphism and worker response to queen pheromone. | queen pheromones are chemical signals produced by reproductive individuals in social insect colonies. in many species they are key to the maintenance of reproductive division of labor, with workers beginning to reproduce individually once the queen pheromone disappears. recently, a queen pheromone that negatively affects worker fecundity was discovered in the bumblebee bombus terrestris, presenting an exciting opportunity for comparisons with analogous queen pheromones in independently-evolved e ... | 2014 | 25289189 |
| 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 |
| divergent rules for pollen and nectar foraging bumblebees--a laboratory study with artificial flowers offering diluted nectar substitute and pollen surrogate. | almost all bees collect nectar and pollen from flowers. female bees collect pollen to provision their nest cells, whereas they use nectar for individual energy supply and nest cell provisioning. bees fine-tune nectar foraging to the amount and to the concentration of nectar, but the individual bees' response to variability of amount and concentration of pollen reward has not yet been studied thoroughly in laboratory settings. we developed an experimental set-up in which bumblebees simultaneously ... | 2014 | 24637406 |
| can bees see at a glance? | primates can analyse visual scenes extremely rapidly, making accurate decisions for presentation times of only 20 ms. we asked whether bumblebees, despite having potentially more limited processing power, could similarly detect and discriminate visual patterns presented for durations of 100 ms or less. bumblebees detected stimuli and discriminated between differently oriented and coloured stimuli when presented as briefly as 25 ms but failed to identify ecologically relevant shapes (predatory sp ... | 2014 | 24625647 |
| commercial bumblebee hives to assess an anthropogenic environment for pollinator support: a case study in the region of ghent (belgium). | anthropogenic changes of the environment influence the distribution and abundance of pollinators such as bumblebees and have been proposed as one of the main causes in their worldwide decline. in order to evaluate the impact of expanding anthropogenic landscapes on supporting pollinator potential, reliable tools are needed. bombus terrestris is one of the most abundant bumblebee species in europe, and these bumblebees are known as generalist pollinators of not only wild flowers in nature but als ... | 2014 | 24297306 |
| isolation and properties of flight muscle mitochondria of the bumblebee bombus terrestris (l.). | this report describes the isolation procedure and properties of tightly coupled flight muscle mitochondria of the bumblebee bombus terrestris (l.). the highest respiratory control index was observed upon oxidation of pyruvate, whereas the highest respiration rates were registered upon oxidation of a combination of the following substrates: pyruvate + malate, pyruvate + proline, or pyruvate + glutamate. the respiration rates upon oxidation of malate, glutamate, glutamate + malate, or succinate we ... | 2013 | 24228879 |
| can winter-active bumblebees survive the cold? assessing the cold tolerance of bombus terrestris audax and the effects of pollen feeding. | there is now considerable evidence that climate change is disrupting the phenology of key pollinator species. the recently reported uk winter activity of the bumblebee bombus terrestris brings a novel set of thermal challenges to bumblebee workers that would typically only be exposed to summer conditions. here we assess the ability of workers to survive acute and chronic cold stress (via lower lethal temperatures and lower lethal times at 0°c), the capacity for rapid cold hardening (rch) and the ... | 2013 | 24224036 |
| dufour's gland secretion, sterility and foraging behavior: correlated behavior traits in bumblebee workers. | bombus terrestris colonies go through two major phases: the "pre-competition phase" in which the queen is the sole reproducer and aggression is rare, and the "competition phase" in which workers aggressively compete over reproduction. conflicts over reproduction are partially regulated by a group of octyl esters that are produced in dufour's gland of reproductively subordinate workers and protect them from being aggressed. however, workers possess octyl esters even before overt aggression occurs ... | 2013 | 24100232 |
| drifting behaviour as an alternative reproductive strategy for social insect workers. | restricted reproduction is traditionally posited as the defining feature of eusocial insect workers. the discovery of worker reproduction in foreign colonies challenges this view and suggests that workers' potential to pursue selfish interests may be higher than previously believed. however, whether such reproductive behaviour truly relies on a reproductive decision is still unknown. workers' reproductive decisions thus need to be investigated to assess the extent of workers' reproductive option ... | 2013 | 24068358 |
| [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 |
| characterisation of a functional allatotropin receptor in the bumblebee, bombus terrestris (hymenoptera, apidae). | allatotropins (ats) are multifunctional neuropeptides initially isolated from the tobacco hornworm, manduca sexta, where they were found to stimulate juvenile hormone synthesis and release from the corpora allata. ats have been found in a wide range of insects, but appear to be absent in drosophila. the first at receptor (atr) was characterised in 2008 in the lepidopteran bombyx mori. since then atrs have been characterised in coleoptera and diptera and in 2012, an at precursor gene was identifi ... | 2013 | 23968772 |
| recruitment to forage of bumblebees in artificial low light is less impaired in light sensitive colonies, and not only determined by external morphological parameters. | bumblebees of bombus terrestris are essential pollinators in natural and managed ecosystems. their foraging ability relies on the individual morphology, task allocation within the colony, and external factors, such as light intensity. the foraging activities of commercial bumblebees can sometimes be impaired, especially in the artificial and weak light intensities of greenhouses at high altitudes. here we investigated whether the eagerness (or willingness) to forage of bumblebee colonies in diff ... | 2013 | 23834824 |
| learning of geometry and features in bumblebees (bombus terrestris). | bumblebees (bombus terrestris) were trained to find one of the four exit holes located in the corners of an enclosed environment with a distinctive geometry (a rectangular cage). panels located at the corners provided nongeometric, featural cues. between trials bumblebees were passively disoriented to disable dead reckoning. when tested after removal of the panels, bumblebees reoriented using the residual information provided by the geometry of the cage. when tested after removal of only the two ... | 2013 | 23815593 |
| patterns of genetic and reproductive traits differentiation in mainland vs. corsican populations of bumblebees. | populations on islands often exhibit lower levels of genetic variation and ecomorphological divergence compared to their mainland relatives. while phenotypic differentiation in characters, such as size or shape among insular organisms, has been well studied, insular differentiation in quantitative reproductive traits involved in chemical communication has received very little attention to date. here, we investigated the impact of insularity on two syntopic bumblebee species pairs: one including ... | 2013 | 23755263 |
| unravelling the mechanisms of trapline foraging in bees. | trapline foraging (repeated sequential visits to a series of feeding locations) is a taxonomically widespread but poorly understood behavior. investigating these routing strategies in the field is particularly difficult, as it requires extensive tracking of animal movements to retrace their complete foraging history. in a recent study, we used harmonic radar and motion-triggered video cameras to track bumblebees foraging between artificial flowers in a large open field. we describe how all bees ... | 2013 | 23750293 |
| assessment of gustatory responses to different sugars in harnessed and free-moving bumblebee workers (bombus terrestris). | for bumblebee colony survival, sugar responses are crucial as nectar is the main carbohydrate source and flower choice is likely determined by sugar composition. this study used a bioassay both with harnessed and with free-moving workers of the bumblebee bombus terrestris to study the gustatory response to the 3 major plant sugars by both groups. in harnessed workers of b. terrestris, a concentration of 5.5% of fructose and glucose was required to induce the proboscis extension reflex in 50% of ... | 2013 | 23599218 |
| membrane filtering properties of the bumblebee (bombus terrestris) photoreceptors across three spectral classes. | filtering properties of the membrane form an integral part of the mechanisms producing the light-induced electrical signal in insect photoreceptors. insect photoreceptors vary in response speed between different species, but recently it has also been shown that different spectral photoreceptor classes within a species possess diverse response characteristics. however, it has not been quantified what roles phototransduction and membrane properties play in such diversity. here, we use electrophysi ... | 2013 | 23571735 |
| dietary chlorantraniliprole suppresses reproduction in worker bumblebees. | pollinators such as the bumblebee, bombus terrestris, fulfil a crucial role in agriculture. in this context, tests were conducted with the insecticide chlorantraniliprole (coragen®) as a model compound active on the ryanodine receptor of insects. | 2013 | 23564706 |
| bumblebee calligraphy: the design and control of flight motifs in the learning and return flights of bombus terrestris. | many wasps and bees learn the position of their nest relative to nearby visual features during elaborate 'learning' flights that they perform on leaving the nest. return flights to the nest are thought to be patterned so that insects can reach their nest by matching their current view to views of their surroundings stored during learning flights. to understand how ground-nesting bumblebees might implement such a matching process, we have video-recorded the bees' learning and return flights and a ... | 2013 | 23447668 |
| detection and learning of floral electric fields by bumblebees. | insects use several senses to forage, detecting floral cues such as color, shape, pattern, and volatiles. we report a formerly unappreciated sensory modality in bumblebees (bombus terrestris), detection of floral electric fields. these fields act as floral cues, which are affected by the visit of naturally charged bees. like visual cues, floral electric fields exhibit variations in pattern and structure, which can be discriminated by bumblebees. we also show that such electric field information ... | 2013 | 23429701 |
| using diagnostic radioentomology for non-invasive observations of colonies of the bumblebee, bombus terrestris. | bumblebees have been the focus of a broad range of scientific research due to their behavior, social life, and a number of other intriguing traits. current methods for examining their nest structure, such as natal cells and contents of storage cells, are destructive in nature because the cells need to be opened for physical inspections. this research describes how the internal structures of the artificial nests of the bumblebee bombus terrestris l. (hymentoptera: apidae) were non-invasively view ... | 2012 | 23421622 |
| serine protease from midgut of bombus terrestris males. | a serine protease was isolated from midguts of the bumblebee male bombus terrestris by a combination of precipitation procedures with column chromatography. the purified enzyme exhibited two bands with molecular masses of 25 and 26 kda as determined by sodium dodecyl sulfate polyacrylamide gel electrophoresis. these bands showed a proteolytic activity in zymography assay. midgut enzymes showed optimum proteolytic activity at ph 9 and 35°c using n-succinyl-l-alanyl-l-alanyl-l-prolyl-l-phenyl-alan ... | 2013 | 23303700 |
| wax lipids signal nest identity in bumblebee colonies. | the signalling functions of cuticular lipids, particularly cuticular hydrocarbons, have gained considerable attention in social insect communication. information transfer between individuals by means of these substances has been examined extensively. however, communication with cuticular lipids is not limited to inter-individual recognition. cuticular compounds can also have a signalling function in the nest environment. workers of the bumblebee bombus terrestris leave cuticular lipid traces, so ... | 2013 | 23288373 |
| daily changes in ultraviolet light levels can synchronize the circadian clock of bumblebees (bombus terrestris). | endogenous circadian clocks are synchronized to the 24-h day by external zeitgebers such as daily light and temperature cycles. bumblebee foragers show diurnal rhythms under daily light:dark cycles and short-period free-running circadian rhythms in constant light conditions in the laboratory. in contrast, during the continuous light conditions of the arctic summer, they show robust 24-h rhythms in their foraging patterns, meaning that some external zeitgeber must entrain their circadian clocks i ... | 2013 | 23281715 |
| reproductive conflict in bumblebees and the evolution of worker policing. | worker policing (mutual repression of reproduction) in the eusocial hymenoptera represents a leading example of how coercion can facilitate cooperation. the occurrence of worker policing in "primitively" eusocial species with low mating frequencies, which lack relatedness differences conducive to policing, suggests that separate factors may underlie the origin and maintenance of worker policing. we tested this hypothesis by investigating conflict over male parentage in the primitively eusocial, ... | 2012 | 23206135 |
| molecular cloning and antifibrinolytic activity of a serine protease inhibitor from bumblebee (bombus terrestris) venom. | bumblebee (bombus spp.) venom contains a variety of components, including bombolitin, phospholipase a(2) (pla(2)), serine proteases, and serine protease inhibitors. in this study, we identified a bumblebee (bombus terrestris) venom serine protease inhibitor (bt-kti) that acts as a plasmin inhibitor. bt-kti consists of a 58-amino acid mature peptide that displays features consistent with snake venom kunitz-type inhibitors, including six conserved cysteine residues and a p1 site. recombinant bt-kt ... | 2013 | 23164714 |
| leg tendon glands in male bumblebees (bombus terrestris): structure, secretion chemistry, and possible functions. | among the large number of exocrine glands described in bees, the tarsal glands were thought to be the source of footprint scent marks. however, recent studies showed that the compounds used for marking by stingless bees are secreted by leg tendon instead of tarsal glands. here, we report on the structure of leg tendon glands in males of bombus terrestris, together with a description of the chemical composition of their secretions and respective changes of both during the males' lives. the ultras ... | 2012 | 23111660 |
| the ant genomes have been invaded by several types of mariner transposable elements. | to date, only three types of full-length mariner elements have been described in ants, each one in a different genus of the myrmicinae subfamily: sinvmar was isolated from various solenopsis species, myrmar from myrmica ruginodis, and mboumar from messor bouvieri. in this study, we report the coexistence of three mariner elements (tnigmar-si, tnigmar-mr, and tnigmar-mb) in the genome of a single species, tapinoma nigerrimum (subfamily dolichoderinae). molecular evolutionary analyses of the nucle ... | 2012 | 23097152 |
| no trade-off between learning speed and associative flexibility in bumblebees: a reversal learning test with multiple colonies. | potential trade-offs between learning speed and memory-related performance could be important factors in the evolution of learning. here, we test whether rapid learning interferes with the acquisition of new information using a reversal learning paradigm. bumblebees (bombus terrestris) were trained to associate yellow with a floral reward. subsequently the association between colour and reward was reversed, meaning bees then had to learn to visit blue flowers. we demonstrate that individuals tha ... | 2012 | 23028779 |
| potential increase in mating frequency of queens in feral colonies of bombus terrestris introduced into japan. | with the exception of several species, bumblebees are monandrous. we examined mating frequency in feral colonies of the introduced bumblebee bombus terrestris in japan. using microsatellite markers, genotyping of sperm dna stored in the spermatheca of nine queens detected multiple insemination paternities in one queen; the others were singly mated. the average effective paternity frequency estimated from the genotypes of queens and workers was 1.23; that estimated from the workers' genotype alon ... | 2012 | 22976124 |
| spatial reorientation by geometry in bumblebees. | human and non-human animals are capable of using basic geometric information to reorient in an environment. geometric information includes metric properties associated with spatial surfaces (e.g., short vs. long wall) and left-right directionality or 'sense' (e.g. a long wall to the left of a short wall). however, it remains unclear whether geometric information is encoded by explicitly computing the layout of surface geometry or by matching images of the environment. view-based spatial encoding ... | 2012 | 22624033 |
| study of local anaesthetics--part 196 formulation of the local anaesthetic heptacaine into hydrogel on the basis of chitosan. | the study aimed to formulate the local anaesthetic heptacaine into hydrogels on the basis of chitosan. the gel-creating compounds used included natural polymers --three different types of chitosan, namely those of a medium molecular weight, from the shells of shrimp, and from the bumblebees species bombus terrestris. the prepared hydrogels were evaluated on the basis of their rheological properties and drug liberation. from the point of drug liberation and flow properties, the optimal gel compos ... | 2012 | 22536655 |
| miniature-dispenser-based bioassay to evaluate the compatibility of powder formulations used in an entomovectoring approach. | entomovectoring as a plant protection strategy demands the design of an appropriate bioassay to assess the risks of potential side effects of the powder formulations in the dispenser towards the vectoring insect. this study reports on the development of a laboratory miniature-dispenser-based bioassay. this bioassay system was used to investigate the compatibility of five model products, prestop-mix, signum, kaolin, wheat flour and cellulose, with the bumblebee, bombus terrestris l. | 2012 | 22328246 |
| trade-off between travel distance and prioritization of high-reward sites in traplining bumblebees. | 1.animals exploiting renewable resource patches are faced with complex multi-location routing problems. in many species, individuals visit foraging patches in predictable sequences called traplines. however, whether and how they optimize their routes remains poorly understood.2.in this study, we demonstrate that traplining bumblebees (bombus terrestris) make a trade-off between minimizing travel distance and prioritizing the most rewarding feeding locations.3.individual bees trained to forage on ... | 2011 | 22267886 |
| neither protogynous nor obligatory out-crossed: pollination biology and breeding system of the european red list fritillaria meleagris l. (liliaceae). | for 4 years we studied pollination biology and breeding system of the critically endangered, red list plant fritillaria meleagris l. (liliaceae), in the larger of the two remaining populations of the plant in se poland. our observations indicated that, contrary to literature data, the species is not dichogamous nor is it obligatorily out-crossing. selfing, although rare in natural populations, results in fully developed seeds. flowers are visited by several insect species, mostly social and soli ... | 2012 | 21972995 |
| bees do not use nearest-neighbour rules for optimization of multi-location routes. | animals collecting patchily distributed resources are faced with complex multi-location routing problems. rather than comparing all possible routes, they often find reasonably short solutions by simply moving to the nearest unvisited resources when foraging. here, we report the travel optimization performance of bumble-bees (bombus terrestris) foraging in a flight cage containing six artificial flowers arranged such that movements between nearest-neighbour locations would lead to a long suboptim ... | 2012 | 21849311 |
| changes in the composition of triacylglycerols in the fat bodies of bumblebee males during their lifetime. | the age-dependent changes in the composition of triacylglycerols (tag) in the fat bodies of bumblebee males were studied using hplc/ms. two related species (bombus terrestris and b. lucorum) were compared, with the age of the males being 0-30 days. the total amount of tag in b. lucorum was about 2.7 times higher than that in b. terrestris for all of the ages studied. one to three-day-old males had the highest content of tag in their fat bodies (1.6-2.3 mg/individual in b. terrestris and 3.8-4.2 ... | 2011 | 21720931 |
| assessment of side-effects by ludox tma silica nanoparticles following a dietary exposure on the bumblebee bombus terrestris. | we assessed lethal and sublethal side-effects of ludox tma silica nanoparticles on a terrestrial pollinator, bombus terrestris (linnaeus), via a dietary exposure. dynamic light scattering analysis confirmed that silica ludox tma nanoparticles remained in suspension in the drinking sugar water. exposure of bumblebee microcolonies during 7 weeks to the different nanoparticle concentrations (high: 34, 170 and 340 mg/l and low: 34 and 340 μg/l) did not cause worker mortality compared to the controls ... | 2012 | 21675822 |
| space use of bumblebees (bombus spp.) revealed by radio-tracking. | accurate estimates of movement behavior and distances travelled by animals are difficult to obtain, especially for small-bodied insects where transmitter weights have prevented the use of radio-tracking. | 2011 | 21603569 |
| lethal and sublethal side-effect assessment supports a more benign profile of spinetoram compared with spinosad in the bumblebee bombus terrestris. | this study was undertaken to identify the potential side effects of the novel naturalyte insecticide spinetoram in comparison with spinosad on the bumblebee bombus terrestris l. the potential lethal effects together with the ecologically relevant sublethal effects on aspects of bumblebee reproduction and foraging behaviour were evaluated. bumblebee workers were exposed via direct contact with wet and dry residues under laboratory conditions to spinetoram at different concentrations, starting fro ... | 2011 | 21472971 |
| the effect of group size on the interplay between dominance and reproduction in bombus terrestris. | social insects provide good model systems for testing trade-offs in decision-making because of their marked reproductive skew and the dilemma workers face when to reproduce. attaining reproductive skew requires energy investment in aggression or fertility signaling, creating a trade-off between reproduction and dominance. this may be density-dependent because the cost of achieving dominance may be higher in larger groups. we investigated the effect of group-size in b. terrestris queenless worker ... | 2011 | 21464893 |
| conspecifics as informers and competitors: an experimental study in foraging bumble-bees. | conspecifics are usually considered competitors negatively affecting food intake rates. however, their presence can also inform about resource quality by providing inadvertent social information. few studies have investigated whether foragers perceive conspecifics as informers or competitors. here, we experimentally tested whether variation in the density of demonstrators ('none', 'low' and 'high'), whose location indicated flower profitability, affected decision-making of bumble-bees bombus ter ... | 2011 | 21288951 |
| impact of a perfluorinated organic compound pfos on the terrestrial pollinator bombus terrestris (insecta, hymenoptera). | perfluorinated organic chemicals like perfluorooctane sulfonic acid (pfos) are persistent environmental pollutants that have been measured in a great diversity of wildlife worldwide, especially in the aquatic compartment. however, little information is available on the presence and effects of pfos in the terrestrial compartment. therefore, we investigated in this project the risks for effects, bioaccumulation and potential mechanisms of activity of pfos in the bumblebee bombus terrestris l. (hym ... | 2011 | 21253836 |
| age- and task-dependent foraging gene expression in the bumblebee bombus terrestris. | in eusocial insects, the division of labor within a colony, based on either age or size, is correlated with a differential foraging (for) gene expression and pkg activity. this article presents in the first part a study on the for gene, encoding a cgmp-dependent protein kinase (pkg) in the bumblebee bombus terrestris. cloning of the open reading frame allowed phylogenetic tracing, which showed conservation of pkgs among social insects. our results confirm the proposed role for pkgs in division o ... | 2011 | 21136525 |
| circadian foraging rhythms of bumblebees monitored by radio-frequency identification. | circadian clocks enable organisms to anticipate changes of environmental conditions. in social insects, the colony as a superorganism has a foraging rhythm aligned to the diurnal patterns of resource availability. within this colony rhythm, the diurnal patterns of individuals are embedded, and various tasks within the colony are performed at different times by different individuals to best serve the colony as a whole. recent studies have shown that social cues influence the traits of the circadi ... | 2010 | 20679495 |
| bumblebee foraging rhythms under the midnight sun measured with radiofrequency identification. | in the permanent daylight conditions north of the arctic circle, there is a unique opportunity for bumblebee foragers to maximise intake, and therefore colony growth, by remaining active during the entire available 24-h period. we tested the foraging rhythms of bumblebee (bombus terrestris and b. pascuorum) colonies in northern finland during the summer, when the sun stays above the horizon for weeks. we used fully automatic radio-frequency identification to monitor the foraging activity of more ... | 2010 | 20587015 |
| applying geographic profiling used in the field of criminology for predicting the nest locations of bumble bees. | we tested whether geographic profiling (gp) can predict multiple nest locations of bumble bees. gp was originally developed in the field of criminology for predicting the area where an offender most likely resides on the basis of the actual crime sites and the predefined probability of crime interaction. the predefined probability of crime interaction in the gp model depends on the distance of a site from an offender's residence. we applied gp for predicting nest locations, assuming that foragin ... | 2010 | 20394756 |
| compatibility of traditional and novel acaricides with bumblebees (bombus terrestris): a first laboratory assessment of toxicity and sublethal effects. | this project assessed the potential hazards of different classical and novel acaricides against an important non-target and beneficial insect for the pollination of wild flowers and cultivated crops, the bumblebee bombus terrestris (l). twenty-three acaricides used commercially in the control of phytophagous mites (acari) were tested in greenhouses and/or the open field. side effects included acute mortality and also sublethal effects on nest reproduction. the different compounds were administer ... | 2010 | 20309850 |
| differences in photoreceptor processing speed for chromatic and achromatic vision in the bumblebee, bombus terrestris. | fast detection of visual change can be mediated by visual processes that ignore chromatic aspects of the visual signal, relying on inputs from a single photoreceptor class (or pooled input from similar classes). there is an established link between photoreceptor processing speed (in achromatic vision) and visual ecology. highly maneuverable flies, for example, have the fastest know photoreceptors, relying on metabolically expensive membrane conductances to boost performance. less active species ... | 2010 | 20237260 |
| a comparison of hplc/apci-ms and maldi-ms for characterising triacylglycerols in insects: species-specific composition of lipids in the fat bodies of bumblebee males. | two mass spectrometric methods for analysing triacylglycerols (hplc/apci-ms and maldi-ms) were used and compared in terms of the relevance of the data for further biostatistical evaluation. while maldi-ms is simpler and significantly faster, the time-consuming and labour-intensive hplc/apci-ms provides more complete information about the lipid components. however, both methods provide well-comparable results concerning the grouping of specimens belonging to different species when evaluated with ... | 2009 | 19819198 |
| preferred viewing directions of bumblebees (bombus terrestris l.) when learning and approaching their nest site. | many bees and wasps learn about the immediate surroundings of their nest during learning flights, in which they look back towards the nest and acquire visual information that guides their subsequent returns. visual guidance to the nest is simplified by the insects' tendency to adopt similar viewing directions during learning and return flights. to understand better the factors determining the particular viewing directions that insects choose, we have recorded the learning and return flights of a ... | 2009 | 19801423 |
| novel microsatellite dna loci for bombus terrestris (linnaeus, 1758). | we present details and characteristics of 123 novel polymorphic microsatellite dna loci for bombus terrestris. thirty-four of these loci have been tested in nine other bombus species and 25 of them showed polymorphisms in at least one species. these microsatellite dna loci together with the already established 60 loci will be useful for characterizing wild and managed populations of b. terrestris and other bombus species as well as for detailed genetic studies in including mapping studies and ge ... | 2009 | 21564905 |
| impacts of inbreeding on bumblebee colony fitness under field conditions. | inbreeding and the loss of genetic diversity are known to be significant threats to small, isolated populations. hymenoptera represent a special case regarding the impact of inbreeding. haplodiploidy may permit purging of deleterious recessive alleles in haploid males, meaning inbreeding depression is reduced relative to diploid species. in contrast, the impact of inbreeding may be exacerbated in hymenopteran species that have a single-locus complementary sex determination system, due to the pro ... | 2009 | 19573223 |
| bumble-bees learn the value of social cues through experience. | natural selection should lead animals to use social cues (sc) when they are useful, and disregard them when they are not. theoretical investigation predicts that individuals should thus employ social learning 'strategies', but how might such context specificity be achieved on a proximate level? operant conditioning, whereby the use of sc is reinforced through rewarding results, provides a potential mechanism. we investigate the role of reinforcement in joining behaviour in bumble-bees, bombus te ... | 2009 | 19324653 |
| lifetime reproductive success and longevity of queens in an annual social insect. | although central to understanding life-history evolution, the relationship between lifetime reproductive success and longevity remains uncertain in many organisms. in social insects, no studies have reported estimates of queens' lifetime reproductive success and longevity within populations, despite the importance of understanding how sociality and associated within-group conflict affect life-history traits. to address this issue, we studied two samples of colonies of the annual bumblebee, bombu ... | 2009 | 19298495 |
| male flight distance and population substructure in the bumblebee bombus terrestris. | 1. bumblebees are important pollinators in natural as well as agricultural ecosystems. estimates of foraging range, population size and genetic population structure so far have been based on worker samples alone. here we include both males and workers in a population genetic analysis to infer the contribution of males to these important ecological parameters. 2. the population genetic (microsatellite) analyses of bombus terrestris l. populations on the island of cabrera (spain) and halle (german ... | 2009 | 19120605 |
| floral iridescence, produced by diffractive optics, acts as a cue for animal pollinators. | iridescence, the change in hue of a surface with varying observation angles, is used by insects, birds, fish, and reptiles for species recognition and mate selection. we identified iridescence in flowers of hibiscus trionum and tulipa species and demonstrated that iridescence is generated through diffraction gratings that might be widespread among flowering plants. although iridescence might be expected to increase attractiveness, it might also compromise target identification because the object ... | 2009 | 19119235 |
| teppeki, selective insecticide about bombus terrestris. | at a time when a highly controversial debate about the causes of the widespread deaths of bees is taking place all over europe, which accused the agriculture and its practices with particular reference to the harmful effects of some insecticides, it seems important to point out as another insecticide, the teppeki, can be selective about bumble and have a good compatibility with the activity of the apiaries. this insecticide has the active ingredient flonicamid (500 g/kg) belonging to a new chemi ... | 2009 | 20222598 |
| intraspecific variation of the cephalic labial gland secretions in bombus terrestris (l.) (hymenoptera: apidae). | variations of secretions of the cephalic part of the labial glands from four different subspecies of bombus terrestris, b. t. terrestris, b. t. lusitanicus, b. t. sassaricus, and b. t. dalmatinus, were investigated. 95 compounds were detected in the whole data set: 54 in b. t. terrestris, 54 in b. t. lusitanicus, 48 in b. t. sassaricus, and 44 in b. t. dalmatinus. the (e)-2,3-dihydrofarnesol is the main compound in b. t. dalmatinus and b. t. sassaricus, while it is dihydrofarnesyl dodecanoate in ... | 2008 | 19089823 |
| aerodynamic sound generation of flapping wing. | the unsteady flow and acoustic characteristics of the flapping wing are numerically investigated for a two-dimensional model of bombus terrestris bumblebee at hovering and forward flight conditions. the reynolds number re, based on the maximum translational velocity of the wing and the chord length, is 8800 and the mach number m is 0.0485. the computational results show that the flapping wing sound is generated by two different sound generation mechanisms. a primary dipole tone is generated at w ... | 2008 | 18646956 |
| immune response impairs learning in free-flying bumble-bees. | parasites can influence different host behaviours including foraging, mate choice and predator avoidance. several recent papers have shown reduced learning abilities in infected insects. however, it is difficult to separate the effects of the immune response from the direct effects of the parasite. using a free-flying learning paradigm, this paper shows that learning performance is impaired in bumble-bees (bombus terrestris) that are not infected but whose immune system is stimulated non-pathoge ... | 2008 | 18628116 |
| social transmission of nectar-robbing behaviour in bumble-bees. | social transmission of acquired foraging techniques is rarely considered outside of a vertebrate context. here, however, we show that nectar robbing by bumble-bees (bombus terrestris)-an invertebrate behaviour of considerable ecological significance-has the potential to spread through a population at the accelerated rates typical of social transmission. nectar robbing occurs when individuals either bite through the base of a flower to 'steal' nectar (primary robbing) or use robbing holes that ot ... | 2008 | 18430642 |
| age-dependent changes in the chemistry of exocrine glands of bombus terrestris queens. | extracts of three different glands (mandibular, labial, and dufour's) of virgin bombus terrestris queens at ten different ages (1-8, 12, and 18 days) were analyzed for chemical composition. one hundred and twenty-seven compounds were identified in the extracts. the mandibular and labial glands contained previously reported electroantennogram-active compounds (3-hydroxydecanoic acid, fatty acids of different chain lengths, their esters, and heptacosene). these compounds reached a maximum concentr ... | 2008 | 18369674 |
| fertility signals in the bumblebee bombus terrestris (hymenoptera: apidae). | in eusocial hymenoptera, queen control over workers is probably inseparable from the mechanism of queen recognition. in primitively eusocial bumblebees (bombus), worker reproduction is controlled not only by the presence or absence of a dominant queen but also by other dominant workers. furthermore, it was shown that the queen dominance is maintained by pheromonal cues. we investigated whether there is a similar odor signal released by egg-laying queens and workers that may have a function as a ... | 2008 | 18320160 |
| modified slca algorithm for full-sib reconstruction of haplodiploid species. | full-sib reconstruction from molecular marker data in the absence of parental information is an active research area. such analyses can provide useful information for studies of mating systems and gene flow, and for estimating effective population size in the wild. although various methods have been proposed, but their estimation accuracies for some applications are not known. here we propose a modified version of shared loci correspondence analysis (mslca) to reconstruct full-sib families of ha ... | 2007 | 18284781 |
| demographic consequences of drift in contiguous hives of bombus terrestris. | the objective of this experiment was 1) to quantify drift between bumblebee, bombus terrestris l., colonies when hives are vertically stacked; and 2) to measure the impact of drift on the colony growth. the experiment was conducted outside, in an open area, at three sites with one stack of three colonies per site. observations were made from the 28th to the 58th d of the colony development, before the competition point. bumblebees were regularly marked with a colony-specific color to access the ... | 2007 | 18232391 |
| age-dependent changes in structure and function of the male labial gland in bombus terrestris. | the cephalic region of the labial gland in the buff-tailed bumblebee, bombus terrestris, consists of numerous acini (formed by associated secretory cells and a central lumen) and connecting ducts. age-dependent changes in secretion production (both qualitative and quantitative) are associated with changes in the amount of rough endoplasmic reticulum (rer), golgi apparatus, and smooth endoplasmic reticulum (ser). the main secretory organelle is rer in the youngest individuals (pharate, and less-t ... | 2008 | 17950308 |
| invasion success of the bumblebee, bombus terrestris, despite a drastic genetic bottleneck. | in early 1992, the european bumblebee, bombus terrestris, was first seen in tasmania and currently has spread to most of the island. here, we report on the genetic structure, using micro-satellites, of the invading population from samples collected in the years 1998-2000, a few years after the first sighting of the species in its new area. the data show that the tasmanian population has a very low genetic diversity, with less than half of the allelic richness (richness=2.89 alleles; h(exp)=0.591 ... | 2007 | 17551520 |
| size determines antennal sensitivity and behavioral threshold to odors in bumblebee workers. | the eusocial bumblebees exhibit pronounced size variation among workers of the same colony. differently sized workers engage in different tasks (alloethism); large individuals are found to have a higher probability to leave the colony and search for food, whereas small workers tend to stay inside the nest and attend to nest duties. we investigated the effect of size variation on morphology and physiology of the peripheral olfactory system and the behavioral response thresholds to odors in worker ... | 2007 | 17479233 |
| the genetic architecture of immune defense and reproduction in male bombus terrestris bumblebees. | understanding the architecture of genetic variation, that is the number, effect, location, and interaction, of genes responsible for phenotypic variability in nature is important for the understanding of microevolutionary processes. in this study, we have used a quantitative trait loci (qtl) approach to uncover the genetic architecture of fitness-relevant traits associated with reproduction and immune defense in male bombus terrestris bumblebees. three male reproductive investment traits, the nu ... | 2007 | 17439613 |
| photoreceptor spectral sensitivity in island and mainland populations of the bumblebee, bombus terrestris. | most species of flower-visiting hymenoptera are trichromatic, with photoreceptor spectral sensitivity peaks in the uv, blue and green regions of the spectrum. red flowers, therefore, should be relatively difficult to detect for such insects. nevertheless, in population biological studies in the bumblebee, bombus terrestris, the sardinian island population (b. t. sassaricus) displayed significantly higher responses to red artificial flowers (in tests of innate colour choice and detectability) tha ... | 2007 | 17333207 |
| a core linkage map of the bumblebee bombus terrestris. | the bumblebee bombus terrestris is an economically important pollinator and an emerging model species in quantitative and population genetics. we generated genetic linkage maps for 3 independent mapping populations of b. terrestris. the linkage map with the highest resolution had 21 linkage groups, which adequately represents the haploid chromosome number of b. terrestris (n = 18). this map can be considered saturated, with an average marker distance of 10.3 cm and an estimated genome coverage o ... | 2006 | 17213903 |
| pollen foraging: learning a complex motor skill by bumblebees (bombus terrestris). | to investigate how bumblebees (bombus terrestris) learn the complex motor skills involved in pollen foraging, we observed naïve workers foraging on arrays of nectarless poppy flowers (papaver rhoeas) in a greenhouse. foraging skills were quantified by measuring the pollen load collected during each foraging bout and relating this to the number of flowers visited and bout duration on two consecutive days. the pollen standing crop (psc) in each flower decreased drastically from 0530 to 0900 hours. ... | 2007 | 17149583 |
| spatial distribution of bumblebees foraging on two cultivars of tomato in a commercial greenhouse. | the spatial distribution of foraging bumblebees, bombus terrestris l. (hymenoptera: apidae), was studied in a greenhouse planted with two cultivars of tomato, lycopersicum esculentum mill. (solanaceae), in two patches. in both patches, bumblebee densities per square meter were measured on plots, and the results showed that their densities were nearly similar. the densities of available flowers, their pollen production, and availability also were measured. our results showed that, although the cu ... | 2006 | 17066784 |
| bumblebees can be used in combination with juvenile hormone analogues and ecdysone agonists. | this study examined the lethal and sublethal effects on the beneficial insect bombus terrestris by two classes of insect growth regulators (igrs) that are commercially used in agriculture to control pest insects. three juvenile hormones analogues (jhas) (pyriproxyfen, fenoxycarb and kinoprene) and two ecdysone agonists or moulting accelerating compounds (macs) (tebufenozide and methoxyfenozide) were tested. the bumblebee workers were exposed to the insecticides via three different routes of expo ... | 2006 | 16988884 |
| isolation and characterization of chitin from bumblebee (bombus terrestris). | insect chitin possessing shell-like structure was prepared from the bumblebee corpses by a consequent treatment with 1m hcl and 1m naoh. the bumblebee chitin was compared with crustacean (shrimp) chitin by using elemental analysis, fourier-transform infrared (ft-ir) and solid-state (13)c cross-polarization magic angle spinning nuclear magnetic resonance (cp/mas)-nmr spectroscopy and confocal microscopy. both chitins (bumblebee and shrimp) exhibited identical spectra, while the bumblebee chitin h ... | 2007 | 16949663 |
| behavioural ecology: bees associate warmth with floral colour. | floral colour signals are used by pollinators as predictors of nutritional rewards, such as nectar. but as insect pollinators often need to invest energy to maintain their body temperature above the ambient temperature, floral heat might also be perceived as a reward. here we show that bumblebees (bombus terrestris) prefer to visit warmer flowers and that they can learn to use colour to predict floral temperature before landing. in what could be a widespread floral adaptation, plants may modulat ... | 2006 | 16885975 |
| heritability of sperm length in the bumblebee bombus terrestris. | sperm length is highly variable, both between and within species, but the evolutionary significance of this variation is poorly understood. sexual selection on sperm length requires a significant additive genetic variance, but few studies have actually measured this. here we present the first estimates of narrow sense heritability of sperm length in a social insect, the bumblebee bombus terrestris. in spite of a balanced and straightforward rearing design of colonies, and the possibility to repl ... | 2006 | 16850209 |
| an immune response in the bumblebee, bombus terrestris leads to increased food consumption. | the concept of a costly immune system that must be traded off against other important physiological systems is fundamental to the burgeoning field of ecological immunity. bumblebees have become one of the central models in this field. although previous work has demonstrated costs of immunity in numerous life history traits, estimates of the more direct costs of bumblebee immunity have yet to be made. | 2006 | 16846495 |
| hazards and uptake of chitin synthesis inhibitors in bumblebees bombus terrestris. | this research project examined the potential hazards of a major class of insect growth regulators (igrs) to survival, reproduction and larval growth in bumblebees bombus terrestris l. eight chitin synthesis inhibitors (csis) were tested: buprofezin, cyromazine, diflubenzuron, flucycloxuron, flufenoxuron, lufenuron, novaluron and teflubenzuron. these different igrs, which are important in the control of pest insects in greenhouses, were applied via three different routes of exposure under laborat ... | 2006 | 16786494 |
| the safety of thiamethoxam to pollinating bumble bees (bombus terrestris l.) when applied to tomato plants through drip irrigation. | thiamethoxam, mainly sold under the trademark of actara, is a neonicotinoid widely used in covered vegetables for the control of aphids and whiteflies. in these crops, and particularly in covered tomatoes, bumble-bees are used for cross-pollination as an alternative to labour intensive manual techniques. in this study, made on tomatoes grown in separated greenhouse plots in murcia, southern spain, thiamethoxam was applied through drip irrigation at a rate of 200 g ai/ha, and as a split applicati ... | 2005 | 16628891 |
| visual targeting of components of floral colour patterns in flower-naïve bumblebees (bombus terrestris; apidae). | floral colour patterns are contrasting colour patches on flowers, a part of the signalling apparatus that was considered to display shape and colour signals used by flower-visitors to detect flowers and locate the site of floral reward. here, we show that flower-naïve bumblebees (bombus terrestris) spontaneously direct their approach towards the outside margin of artificial flowers, which provides contrast between these dummy flowers and the background. if no floral guides are present, the bumbl ... | 2006 | 16568268 |
| identification of queen sex pheromone components of the bumblebee bombus terrestris. | we investigated the origin and chemical composition of the queen sex pheromone of the primitively eusocial bumblebee, bombus terrestris (apidae). physiologically and behaviorally active compounds were identified by coupled gas chromatography electro-antennography (gc-ead), gas chromatography-mass spectrometry (gc-ms), and laboratory behavioral tests. in the behavioral assays, virgin queens frozen previously at -20 degrees c were highly attractive to males. dummies impregnated with surface and ce ... | 2006 | 16555129 |
| developmentally determined attenuation in circadian rhythms links chronobiology to social organization in bees. | we investigated labor-related plasticity in the circadian clock of the bumblebee bombus terrestris. bumblebee workers vary enormously in body size, and we found that size, division of labor, and diurnal rhythms in activity are correlated in b. terrestris colonies. large workers typically perform foraging activities with strong diurnal rhythms and low activity at night, whereas small bees typically care for (nurse) brood around the clock with weak or no diurnal rhythms. under constant laboratory ... | 2006 | 16513930 |
| insect psychoneuroimmunology: immune response reduces learning in protein starved bumblebees (bombus terrestris). | it is well established in vertebrates that there are many intricate interactions between the immune system and the nervous system. here, we present behavioural evidence indicating a link between the immune system and the nervous system in insects. we show that otherwise non-infected bumblebees whose immune systems were challenged by a non-pathogenic immunogenic elicitor (lipopolysaccharide) have reduced abilities to learn or recall a memory in a classical conditioning paradigm. there is evidence ... | 2006 | 16084688 |
| ace inhibitory activity in enzymatic hydrolysates of insect protein. | in this paper, ace inhibitory activity in insect protein hydrolyzed by various enzymes (gastrointestinal proteases, alcalase, and thermolysin) is reported for the first time. four insects of different insect orders were tested: spodoptera littoralis (lepidoptera), bombyx mori (lepidoptera), schistocerca gregaria (orthoptera), and bombus terrestris (hymenoptera). ace inhibitory activity was measured by two different methods: a spectrophotometric method using fapgg (2-furanacryloyl-phenylalanyl-gl ... | 2005 | 15969498 |
| pyridalyl, a novel insecticide: potency and insecticidal selectivity. | pyridalyl is an insecticide of a novel chemical class (unclassified insecticides). toxicity of pyridalyl to two insect pest species, spodoptera litura and frankliniella occidentalis, an insect predator, orius stringicollis, and a pollinator, bombus terrestris, was evaluated in the laboratory. the insecticidal activity of pyridalyl against s. litura was evaluated using the leaf-dipping method. the potency of pyridalyl was highly effective against all development stages (2nd to 6th instar larvae) ... | 2005 | 15756699 |
| seeing the light: illumination as a contextual cue to color choice behavior in bumblebees. | the principal challenge faced by any color vision system is to contend with the inherent ambiguity of stimulus information, which represents the interaction between multiple attributes of the world (e.g., object reflectance and illumination). how natural systems deal with this problem is not known, although traditional hypotheses are predicated on the idea that vision represents object reflectance accurately by discounting early in processing the conflating effects of illumination. here, we test ... | 2005 | 15731346 |
| bumblebees (bombus terrestris) sacrifice foraging speed to solve difficult colour discrimination tasks. | the performance of individual bumblebees at colour discrimination tasks was tested in a controlled laboratory environment. bees were trained to discriminate between rewarded target colours and differently coloured distractors, and then tested in non-rewarded foraging bouts. for the discrimination of large colour distances bees made relatively fast decisions and selected target colours with a high degree of accuracy, but for the discrimination of smaller colour distances the accuracy decreased an ... | 2004 | 15316731 |
| does the queen win it all? queen-worker conflict over male production in the bumblebee, bombus terrestris. | social insects provide a useful model for studying the evolutionary balance between cooperation and conflict linked to genetic structure. we investigated the outcome of this conflict in the bumblebee, bombus terrestris, whose annual colony life cycle is characterized by overt competition over male production. we established artificial colonies composed of a queen and unrelated workers by daily exchange of callow workers between colony pairs of distinct genetic make-up. using microsatellite analy ... | 2004 | 15278221 |
| symmetry is in the eye of the beeholder: innate preference for bilateral symmetry in flower-naïve bumblebees. | bilateral symmetry has been considered as an indicator of phenotypic and genotypic quality supporting innate preferences for highly symmetric partners. insect pollinators preferentially visit flowers of a particular symmetry type, thus leading to the suggestion that they have innate preferences for symmetrical flowers or flower models. here we show that flower-naïve bumblebees (bombus terrestris), with no experience of symmetric or asymmetric patterns and whose visual experience was accurately c ... | 2004 | 15278213 |
| behavioural interactions, kin and disease susceptibility in the bumblebee bombus terrestris. | behavioural interactions are often analysed in terms of their costs and benefits to the actors [hamilton, (1964) j. theor. biol.7 1-16; gadagkar, (1993) trends ecol. evol.8 232-234; foster et al., (2001) ann. zool. fenn.38 229-238]. using the bumblebee bombus terrestris, we wish to distinguish between two possible determinants of interaction behaviour between conspecifics, namely kin-directed behaviour that reflects genetic distance between individuals, or, alternatively, interactions guided by ... | 2004 | 15271082 |
| cytological evidence for triploid males and females in the bumblebee, bombus terrestris. | the presence of both triploid males and females in bombus terrestris was detected by distinct chromosome observation. these cytological features are novel among the higher hymenopteran insects. we thus strictly applied the complementary sex determination (csd) model previously proposed for hymenopteran insects. three out of 60 sibling queens that were mated with diploid males produced both triploid males and females, and founded colonies. the male to female ratio of the bees which emerged from t ... | 2004 | 15125635 |
| biological significance of distinguishing between similar colours in spectrally variable illumination: bumblebees (bombus terrestris) as a case study. | individual bumblebees were trained to choose between rewarded target flowers and non-rewarded distractor flowers in a controlled illumination laboratory. bees learnt to discriminate similar colours, but with smaller colour distances the frequency of errors increased. this indicates that pollen transfer might occur between flowers with similar colours, even if these colours are distinguishable. the effect of similar colours on reducing foraging accuracy of bees is evident for colour distances hig ... | 2004 | 14652688 |
| interindividual variation of eye optics and single object resolution in bumblebees. | in the eusocial bumblebees, distinct size variation occurs within the worker caste of a colony. we show that there are pronounced differences in compound eye optical quality between individual workers in bombus terrestris. using scanning electron microscopy and antidromic illumination techniques (the pseudopupil method), we demonstrate that large workers have extended facet diameters in conjunction with reduced interommatidial angles. thus, both overall sensitivity and image resolution are super ... | 2003 | 12939375 |
| juvenile hormone titers, juvenile hormone biosynthesis, ovarian development and social environment in bombus terrestris. | the effects of the social environment and age on juvenile hormone (jh) and reproduction were investigated by measuring ovarian development, hemolymph levels of jh iii, and rates of jh biosynthesis from the same individual bumble bees (bombus terrestris). differences in social environment were associated with differences in rates of jh biosynthesis, jh titer and ovarian development. young queenless workers had a higher rate of jh biosynthesis, jh titer and ovarian development than queenright (qr) ... | 2000 | 12770258 |
| males of social insects can prevent queens from multiple mating. | during copulation, males of bombus terrestris fill the queen's sexual tract with a mating plug after transferring their sperm. the sticky secretion is produced by the male's accessory glands and disappears within a couple of days. experiments now show that the primary function of the plug is to reduce the subsequent mating probability of the queen. the plug is not efficient in preventing sperm migration into the spermatheca. due to its low energetic value, the plug is also unlikely to serve as a ... | 2001 | 11454287 |
| hazards of imidacloprid seed coating to bombus terrestris (hymenoptera: apidae) when applied to sunflower. | seed coating treatments of sunflower by the systemic insecticide imidacloprid was suspected of affecting honey bees and bumblebees. the hypothesis raised was whether imidacloprid could migrate into nectar and pollen, then modify flower attractiveness, homing behavior, and colony development. our greenhouse and field experiments with bombus terrestris l. were aimed at the following: the behavior of workers foraging on treated and control plants blooming in a greenhouse, the homing rate of colonie ... | 2001 | 11425015 |
| a nonspecific fatty acid within the bumblebee mating plug prevents females from remating. | the best mating strategy for males differs from that of females, because females gain from mating with several males (polyandry), but males gain from monopolizing the females. as a consequence, males have evolved a variety of methods, such as the transfer of inhibitory substances from their accessory glands, to ensure exclusive paternity of the female's offspring, generally with detrimental effects on female fitness. inhibitory substances have been identified as peptides or other specific molecu ... | 2001 | 11274412 |