| behavioural assessment of visual acuity in bumblebees (bombus impatiens). | the present study used previously developed techniques to measure resolution acuity in bumblebees (bombus impatiens). bees were required to discriminate between horizontal and vertical gratings in a y-maze apparatus. the gratings had a mean luminance of 9 cd m(-)(2) and a michelson contrast of 84 %. for different bees, either the horizontal or vertical grating was rewarded. rewarded gratings were associated with a sucrose and water solution (30 % sucrose by volume) and unrewarded gratings with p ... | 2001 | 11171306 |
| bumble bee (hymenoptera: apidae) activity and pollination levels in commercial tomato greenhouses. | commercial greenhouse studies were conducted to assess levels of pollination of tomato (lycopersicon esculentum mill.) flowers in relation to bumble bee (bombus impatiens cresson) colony activity and colony densities. for the assessment of pollination levels of tomato flowers, five categories were defined based on bruising levels caused by bumble bee pollination. colony activity was measured as bee trips per ha/d using electric powered photodiode monitors inserted into the hive entrance. levels ... | 2001 | 11332840 |
| bombus impatiens (hymenoptera: apidae): an alternative to apis mellifera (hymenoptera: apidae) for lowbush blueberry pollination. | the pollination effectiveness of the commercially reared bumble bee bombus impatiens cresson, was compared in field studies to the honey bee, apis mellifera l., for lowbush blueberry, vaccinium angustifolium ait. a preliminary study indicated that b. impatiens had potential as an alternative pollinator. in a 3-yr study, percentage fruit set, percentage harvested berries, berry weight, and seeds per berry were compared in blueberry fields stocked at 7.5 a. mellifera hives per hectare to 5, 7.5, o ... | 2001 | 11425013 |
| effects of a reward downshift on the consummatory behavior and flower choices of bumblebee foragers. | insect foragers often exhibit flower constancy, the tendency to visit single flower types rather than sample alternative flowers that provide equal or higher levels of reward. we employed a negative incentive contrast procedure to examine whether a decrease of sucrose concentration in a regularly visited flower type affects bumblebee (bombus impatiens) consummatory or choice behavior. subjects were trained to enter a test arena where they foraged on a single, red, artificial flower that containe ... | 2003 | 12954395 |
| early duplication and functional diversification of the opsin gene family in insects. | recent analysis of the complete mosquito anopheles gambiae genome has revealed a far higher number of opsin genes than for either the drosophila melanogaster genome or any other known insect. in particular, the analysis revealed an extraordinary opsin gene content expansion, whereby half are long wavelength-sensitive (lw) opsin gene duplicates. we analyzed this genomic data in relationship to other known insect opsins to estimate the relative timing of the lw opsin gene duplications and to ident ... | 2004 | 15155799 |
| comparison and examination of bombus occidentalis and bombus impatiens (hymenoptera: apidae) in tomato greenhouses. | experiments were conducted in commercial tomato, lycopersicon esculentum miller (solanaceae), greenhouses to compare the relative foraging effort of two bumble bee species, bombus occidentalis greene and bombus impatiens cresson, to examine interspecific competition between b. occidentalis and b. impatiens, and to determine whether bumble bee colonies grew to their full population potential in commercial tomato greenhouses. b. impatiens colonies had more brood and workers and made more foraging ... | 2004 | 15384352 |
| lethal and sub-lethal effects of spinosad on bumble bees (bombus impatiens cresson). | recent developments of new families of pesticides and growing awareness of the importance of wild pollinators for crop pollination have stimulated interest in potential effects of novel pesticides on wild bees. yet pesticide toxicity studies on wild bees remain rare, and few studies have included long-term monitoring of bumble bee colonies or testing of foraging ability after pesticide exposure. larval bees feeding on exogenous pollen and exposed to pesticides during development may result in le ... | 2005 | 15880684 |
| learning in two contexts: the effects of interference and body size in bumblebees. | we examined the effect of learning a new task on the performance of a previously learned task with the same set of visual cues in bumblebees, bombus impatiens. previous studies have shown that given a binary choice at each task, bumblebees do not show retroactive interference, or mistakes in the first task, if the two tasks are in different contexts, feeding and nest location. here we tested whether adding a third, unrewarded choice to each task affects the performance of bees learning in two co ... | 2005 | 15914648 |
| molecular characterization and expression of the uv opsin in bumblebees: three ommatidial subtypes in the retina and a new photoreceptor organ in the lamina. | ultraviolet-sensitive photoreceptors have been shown to be important for a variety of visual tasks performed by bees, such as orientation, color and polarization vision, yet little is known about their spatial distribution in the compound eye or optic lobe. we cloned and sequenced a uv opsin mrna transcript from bombus impatiens head-specific cdna and, using western blot analysis, detected an eye protein band of approximately 41 kda, corresponding to the predicted molecular mass of the encoded o ... | 2005 | 15939775 |
| peak shift discrimination learning as a mechanism of signal evolution. | "peak shift" is a behavioral response bias arising from discrimination learning in which animals display a directional, but limited, preference for or avoidance of unusual stimuli. its hypothesized evolutionary relevance has been primarily in the realm of aposematic coloration and limited sexual dimorphism. here, we develop a novel functional approach to peak shift, based on signal detection theory, which characterizes the response bias as arising from uncertainty about stimulus appearance, freq ... | 2005 | 16050106 |
| spatial encoding by bumblebees (bombus impatiens) of a reward within an artificial flower array. | we presented bumblebees a spatial memory task similar to that used with other species (e.g., cats, dogs, and pigeons). in some conditions we allowed for presence of scent marks in addition to placing local and global spatial cues in conflict. bumblebees (bombus impatiens) were presented an array of artificial flowers within a flight cage, one flower offering reward (s+), while the others were empty (s-). bees were tested with empty flowers. in experiment 1, flowers were either moved at the time ... | 2006 | 16416106 |
| bumble-bee foragers infected by a gut parasite have an impaired ability to utilize floral information. | parasitic infection can influence a variety of behavioural mechanisms in animals, but little is known about the effects of infection on the cognitive processes underlying ecologically relevant behaviours. here, we examined whether parasitic infection alters cognitive aspects of foraging in a social insect, the bumble-bee (bombus impatiens). in controlled experiments, we assessed the ability of foraging bees to discriminate rewarding from non-rewarding flowers on the basis of colour and odour. we ... | 2006 | 16600883 |
| commercial bumble bee bombus impatiens (hymenoptera: apidae) as a pollinator in lowbush blueberry (ericale: ericaceae) fields. | here, we evaluate the potential of the bumble bee bombus impatiens cresson, obtained from commercial colonies, as a pollen vector for lowbush blueberry, vaccinium augustifolium aiton. we wanted to gain insight into the relationships between pollination by introduced bumble bees, the categories of seeds produced, and the weight and the maturity of the blueberries. the effect of b. impatiens foraging in blueberry stands was measured quantitatively through fruit set and seed set analysis. we create ... | 2006 | 16686145 |
| interval timing by an invertebrate, the bumble bee bombus impatiens. | sensitivity to temporal information and the ability to adjust behavior to the temporal structure of the environment should be phylogenetically widespread. some timing abilities, such as sensitivity to circadian cycles, appear in a wide range of invertebrate and vertebrate taxa [1,2]. interval timing--sensitivity to the duration of time intervals--has, however, only been shown to occur in vertebrates [3,4]. insect pollinators make a variety of decisions that would appear to require the ability to ... | 2006 | 16920625 |
| within-host dynamics of an intestinal pathogen of bumble bees. | the success of a pathogen depends not only on its transmission to new hosts, but also on its ability to colonize and persist within its current host. studies of within-host dynamics have focused on only a few diseases of humans, whereas little is known about the factors that influence pathogen populations as they develop inside non-human hosts. here, we investigate pathogen dynamics occurring within bumble bees (bombus impatiens) infected by the gut trypanosome crithidia bombi. infection by c. b ... | 2006 | 16948877 |
| traplining in bumblebees (bombus impatiens): a foraging strategy's ontogeny and the importance of spatial reference memory in short-range foraging. | to test the relative importance of long-term and working spatial memories in short-range foraging in bumblebees, we compared the performance of two groups of bees. one group foraged in a stable array of six flowers for 40 foraging bouts, thereby enabling it to establish a long-term memory of the array, and adjust its spatial movements accordingly. the other group was faced with an array that changed between (but not within) foraging bouts, and thus had only access to a working memory of the flow ... | 2007 | 17136553 |
| flower choice copying in bumblebees. | we tested a hypothesis originating with darwin that bees outside the nest exhibit social learning in flower choices. naive bumblebees, bombus impatiens, were allowed to observe trained bees or artificial bees forage from orange or green flowers. subsequently, observers of bees on green flowers landed more often on green flowers than non-observing controls or observers of models on orange flowers. these results demonstrate that bumblebees can change flower choice by observations of non-nest mates ... | 2005 | 17148244 |
| insect cryptochromes: gene duplication and loss define diverse ways to construct insect circadian clocks. | cryptochrome (cry) proteins are components of the central circadian clockwork of metazoans. phylogenetic analyses show at least 2 rounds of gene duplication at the base of the metazoan radiation, as well as several losses, gave rise to 2 cryptochrome (cry) gene families in insects, a drosophila-like cry1 gene family and a vertebrate-like cry2 family. previous studies have shown that insect cry1 is photosensitive, whereas photo-insensitive cry2 functions to potently inhibit clock-relevant clock:c ... | 2007 | 17244599 |
| ecological context influences pollinator deterrence by alkaloids in floral nectar. | secondary compounds may benefit plants by deterring herbivores, but the presence of these defensive chemicals in floral nectar may also deter beneficial pollinators. this trade-off between sexual reproduction and defense has received minimal study. we determined whether the pollinator-deterring effects of a nectar alkaloid found in the perennial vine gelsemium sempervirens depend on ecological context (i.e. the availability of alternative nectar sources) by monitoring the behavioural response of ... | 2007 | 17498136 |
| floral reward production is timed by an insect pollinator. | interval timing--sensitivity to elapsing durations--has recently been found to occur in an invertebrate pollinator, the bumble-bee (bombus impatiens). here, bumble-bees were required to time the interval between the start of foraging in a patch of low-quality artificial flowers providing 25% sucrose and the availability of a high-quality flower (hqf) that provided 50% sucrose after a fixed delay. the delay changed after every 20 foraging bouts in the order 30-150-30 s. bees visited the hqf soone ... | 2007 | 17519188 |
| habitat assessment ability of bumble-bees implies frequency-dependent selection on floral rewards and display size. | foraging pollinators could visit hundreds of flowers in succession on mass-flowering plants, yet they often visit only a small number--potentially saving the plant from much self-pollination among its own flowers (geitonogamy). this study tests the hypothesis that bumble-bee (bombus impatiens) residence on a particular plant depends on an assessment of that plant's reward value relative to the overall quality experienced in the habitat. in a controlled environment, naive bees were given experien ... | 2007 | 17711839 |
| contact networks and transmission of an intestinal pathogen in bumble bee (bombus impatiens) colonies. | in socially living animals, individuals interact through complex networks of contact that may influence the spread of disease. whereas traditional epidemiological models typically assume no social structure, network theory suggests that an individual's location in the network determines its risk of infection. empirical, especially experimental, studies of disease spread on networks are lacking, however, largely due to a shortage of amenable study systems. we used automated video-tracking to quan ... | 2007 | 17713789 |
| multimodal signals enhance decision making in foraging bumble-bees. | multimodal signals are common in nature and have recently attracted considerable attention. despite this interest, their function is not well understood. we test the hypothesis that multimodal signals improve decision making in receivers by influencing the speed and the accuracy of their decisions. we trained bumble-bees (bombus impatiens) to discriminate between artificial flowers that differed either in one modality, visual (specifically, shape) or olfactory, or in two modalities, visual plus ... | 2008 | 18198150 |
| comparative efficiency of nannotrigona perilampoides, bombus impatiens (hymenoptera: apoidea), and mechanical vibration on fruit production of enclosed habanero pepper. | the native bee nannotrigona perilampoides cresson (apidae: meliponini) has been evaluated with promising results in greenhouse pollination of solanaceae in mexico. however, no comparison has been done with imported bumble bees (apidae: bombini), which are the most common bees used for greenhouse pollination. we compared the foraging activity and fruit production of habanero pepper. capsicum chinense jacquin, by using n. perilampoides and bombus impatiens cresson in pollination cages. both bee sp ... | 2008 | 18330127 |
| visitation by wild and managed bees (hymenoptera: apoidea) to eastern u.s. native plants for use in conservation programs. | addition of floral resources to agricultural field margins has been shown to increase abundance of beneficial insects in crop fields, but most plants recommended for this use are non-native annuals. native perennial plants with different bloom periods can provide floral resources for bees throughout the growing season for use in pollinator conservation projects. to identify the most suitable plants for this use, we examined the relative attractiveness to wild and managed bees of 43 eastern u.s. ... | 2008 | 18559176 |
| the processing of color, motion, and stimulus timing are anatomically segregated in the bumblebee brain. | animals use vision to perform such diverse behaviors as finding food, interacting socially with other animals, choosing a mate, and avoiding predators. these behaviors are complex and the visual system must process color, motion, and pattern cues efficiently so that animals can respond to relevant stimuli. the visual system achieves this by dividing visual information into separate pathways, but to what extent are these parallel streams separated in the brain? to answer this question, we recorde ... | 2008 | 18562602 |
| bumble bees heat up for high quality pollen. | thermoregulation plays a key role in bee foraging, allowing some species to forage in suboptimal temperatures. recently, bumble bee thoracic temperature (t(th)) has been shown to increase with nectar carbohydrate content. however, pollen is also vital to bees and exhibits a greater than 20-fold range in protein quality. we provide the first demonstration that bee t(th) is also correlated with pollen quality. we allowed bumble bee, bombus impatiens, foragers from two colonies to collect pollen va ... | 2008 | 18587118 |
| higher order visual input to the mushroom bodies in the bee, bombus impatiens. | to produce appropriate behaviors based on biologically relevant associations, sensory pathways conveying different modalities are integrated by higher-order central brain structures, such as insect mushroom bodies. to address this function of sensory integration, we characterized the structure and response of optic lobe (ol) neurons projecting to the calyces of the mushroom bodies in bees. bees are well known for their visual learning and memory capabilities and their brains possess major direct ... | 2008 | 18635397 |
| pollinator experience, neophobia and the evolution of flowering time. | environmental changes, such as current climate warming, can exert directional selection on reproductive phenology. in plants, evolution of earlier flowering requires that the individuals bearing genes for early flowering successfully reproduce; for non-selfing, zoophilous species, this means that early flowering individuals must be visited by pollinators. in a laboratory experiment with artificial flowers, we presented captive bumble-bees (bombus impatiens) with flower arrays representing stages ... | 2009 | 19129131 |
| color processing in the medulla of the bumblebee (apidae: bombus impatiens). | the mechanisms of processing a visual scene involve segregating features (such as color) into separate information channels at different stages within the brain, processing these features, and then integrating this information at higher levels in the brain. to examine how this process takes place in the insect brain, we focused on the medulla, an area within the optic lobe through which all of the visual information from the retina must pass before it proceeds to central brain areas. we used his ... | 2009 | 19226517 |
| impact of currently used or potentially useful insecticides for canola agroecosystems on bombus impatiens (hymenoptera: apidae), megachile rotundata (hymentoptera: megachilidae), and osmia lignaria (hymenoptera: megachilidae). | pest management practices may be contributing to a decline in wild bee populations in or near canola (brassica napus l.) agroecosystems. the objective of this study was to investigate the direct contact toxicity of five technical grade insecticides--imidacloprid, clothianidin, deltamethrin, spinosad, and novaluron--currently used, or with potential for use in canola integrated pest management on bees that may forage in canola: common eastern bumble bees [bombus impatiens (cresson); hereafter bum ... | 2009 | 19253634 |
| division of labour within flowers: heteranthery, a floral strategy to reconcile contrasting pollen fates. | in many nectarless flowering plants, pollen serves as both the carrier of male gametes and as food for pollinators. this can generate an evolutionary conflict if the use of pollen as food by pollinators reduces the number of gametes available for cross-fertilization. heteranthery, the production of two or more stamen types by individual flowers reduces this conflict by allowing different stamens to specialize in 'pollinating' and 'feeding' functions. we used experimental studies of solanum rostr ... | 2009 | 19320798 |
| comparative genetic analyses of historical and contemporary collections highlight contrasting demographic histories for the bumble bees bombus pensylvanicus and b. impatiens in illinois. | direct comparison of genetic patterns between museum specimens and contemporary collections can be a powerful approach for detecting recent demographic changes. using microsatellite markers, we examined historical and contemporary genetic variation from an apparently declining bumble bee species, bombus pensylvanicus, and from a stable species, bombus impatiens, in central illinois. for each species, we genotyped specimens from the illinois natural history survey collected from three populations ... | 2009 | 19344350 |
| location, location, location: larvae position inside the nest is correlated with adult body size in worker bumble-bees (bombus impatiens). | social insects display task-related division of labour. in some species, division of labour is related to differences in body size, and worker caste members display morphological adaptations suited for particular tasks. bumble-bee workers (bombus spp.) can vary in mass by eight- to tenfold within a single colony, which previous work has linked to division of labour. however, little is known about the proximate mechanism behind the production of this wide range of size variation within the worker ... | 2009 | 19364744 |
| background complexity affects colour preference in bumblebees. | flowers adapted for hummingbird pollination are typically red. this correlation is usually explained by the assertion that nectar- or pollen-stealing bees are "blind" to red flowers. however, laboratory studies have shown that bees are capable of locating artificial red flowers and often show no innate preference for blue over red. we hypothesised that these findings might be artefacts of the simplified laboratory environment. using bumblebees (bombus impatiens) that had been trained to visit re ... | 2009 | 19444425 |
| bumblebees exhibit the memory spacing effect. | associative learning is key to how bees recognize and return to rewarding floral resources. it thus plays a major role in pollinator floral constancy and plant gene flow. honeybees are the primary model for pollinator associative learning, but bumblebees play an important ecological role in a wider range of habitats, and their associative learning abilities are less well understood. we assayed learning with the proboscis extension reflex (per), using a novel method for restraining bees (capsules ... | 2009 | 19562317 |
| effects of clothianidin on bombus impatiens (hymenoptera: apidae) colony health and foraging ability. | we conducted laboratory experiments to investigate the lethal and sublethal effects of clothianidin on bumble bee, bombus impatiens cresson, colony health and foraging ability. bumble bee colonies were exposed to 6 ppb clothianidin, representing the highest residue levels found in field studies on pollen, and a higher dose of 36 ppb clothianidin in pollen. clothianidin did not effect pollen consumption, newly emerged worker weights, amount of brood or the number of workers, males, and queens at ... | 2004 | 15154457 |
| hazards of insecticides to the bumble bees bombus impatiens (hymenoptera: apidae) foraging on flowering white clover in turf. | insecticides used on turf are sometimes applied to areas with flowering weeds that attract honey bees and native pollinators. we tested residual effects of such treatments on colony vitality and behavior of the bumble bees bombus impatiens cresson foraging on turf containingwhite clover, trifolium repens l. imidacloprid, a syst emic chloronicotinyl used for preventive control of root-feeding grubs, was applied as granules, followed by irrigation, or sprayed as a wettable powder, with or without ... | 2002 | 12216812 |
| partial cytochrome b sequences for six hymenoptera of the eastern united states. | mitochondrial dna (mtdna) haplotypes have been commonly used to determine honeybee subspecies relationships. to see if these markers would also be useful for comparisons of other hymenoptera, we collected workers of six local species: vespa crabro, the european hornet; bombus impatiens, a bumblebee; vespula germanica, the german yellow jacket; polistes fuscatus, a paper wasp; halictus ligatus, an alkali bee; and an unspecified megachile, a leafcutting bee. mtdna was isolated and digested with si ... | 2001 | 11948223 |
| effect of reduced risk pesticides for use in greenhouse vegetable production on bombus impatiens (hymenoptera: apidae). | bumble bees [bombus impatiens (cresson)] are widely used for supplemental pollination of greenhouse vegetables and are at risk of pesticide exposure while foraging. the objective of this study was to determine the lethal and sub-lethal effects of four insecticides (imidacloprid, abamectin, metaflumizone and chlorantraniliprole) and three fungicides (myclobutanil, potassium bicarbonate and cyprodinil + fludioxonil) used or with potential for use in ontario greenhouse vegetable production to b. im ... | 2010 | 19757502 |
| identification of nosema bombi fantham and porter 1914 (microsporidia) in bombus impatiens and bombus sandersoni from great smoky mountains national park (usa). | ninety three bumble bees belonging to the genus bombus, subgenus pyrobombus (three bombus vagans, seven bombus bimaculatus, 17 b. sandersoni and 68 b. impatiens) from great smoky mountains national park were examined for microsporidia. light microscopy of calcoflour and trichrome-stained smears, and pcr revealed infection with n. bombi in one specimen each of b. sandersoni and b. impatiens. sizes and shapes of spores in both n. bombi isolates were similar to those described for european isolates ... | 2010 | 19835879 |
| limits to vertical force and power production in bumblebees (hymenoptera: bombus impatiens). | maximum vertical forces produced by flying animals can be difficult to identify unequivocally, but potentially indicate general limits to aerodynamic force and muscle power output. we used two methods (i.e. incremental addition of supplemental mass and asymptotic load lifting) to determine both the intraspecific allometry of and methodological differences in estimates of maximum flight performance for the bumblebee bombus impatiens. we found that incremental mass addition underestimated maximum ... | 2010 | 20086127 |
| the spatial frequency tuning of optic-flow-dependent behaviors in the bumblebee bombus impatiens. | insects use visual estimates of flight speed for a variety of behaviors, including visual navigation, odometry, grazing landings and flight speed control, but the neuronal mechanisms underlying speed detection remain unknown. although many models and theories have been proposed for how the brain extracts the angular speed of the retinal image, termed optic flow, we lack the detailed electrophysiological and behavioral data necessary to conclusively support any one model. one key property by whic ... | 2010 | 20435814 |
| weather during bloom affects pollination and yield of highbush blueberry. | weather plays an important role in spring-blooming fruit crops due to the combined effects on bee activity, flower opening, pollen germination, and fertilization. to determine the effects of weather on highbush blueberry, vaccinium corymbosum l., productivity, we monitored bee activity and compared fruit set, weight, and seed number in a field stocked with honey bees, apis mellifera l., and common eastern bumble bees, bombus impatiens (cresson). flowers were subjected to one of five treatments d ... | 2010 | 20568598 |
| photoreceptor spectral sensitivity in the bumblebee, bombus impatiens (hymenoptera: apidae). | the bumblebee bombus impatiens is increasingly used as a model in comparative studies of colour vision, or in behavioural studies relying on perceptual discrimination of colour. however, full spectral sensitivity data on the photoreceptor inputs underlying colour vision are not available for b. impatiens. since most known bee species are trichromatic, with photoreceptor spectral sensitivity peaks in the uv, blue and green regions of the spectrum, data from a related species, where spectral sensi ... | 2010 | 20711523 |
| flowers help bees cope with uncertainty: signal detection and the function of floral complexity. | plants often attract pollinators with floral displays composed of visual, olfactory, tactile and gustatory stimuli. since pollinators' responses to each of these stimuli are usually studied independently, the question of why plants produce multi-component floral displays remains relatively unexplored. here we used signal detection theory to test the hypothesis that complex displays reduce a pollinator's uncertainty about the floral signal. specifically, we asked whether one component of the flor ... | 2011 | 21147975 |
| behavioural, morphological, and metabolic maturation of newly emerged adult workers of the bumblebee, bombus impatiens. | newly emerged adult holometabolous insects must still complete considerable morphological, metabolic, and neural maturation. despite this, adults have frequently been documented to fly prior to finishing maturation and attaining peak physiological capacity. in some species, flight is limited by the unfurling of the wing, while in other species it may be limited by biochemical capacity. we charted maturation trajectories of adult bumblebee workers (bombus impatiens) for both morphological and fli ... | 2011 | 21335010 |
| flower morphology and pollinator dynamics in solanum carolinense (solanaceae): implications for the evolution of andromonoecy. | flower morphology and pollinator dynamics play an important role in the evolution and maintenance of many breeding systems, including andromonoecy. we used a series of field experiments to test the functional relationship between flower morphology and pollination dynamics (e.g., pollen receipt and export) in solanum carolinense. we find that long-styled flowers serve primarily as pollen recipients and short-styled flowers as pollen donors, making this the first study to support the male-female i ... | 2008 | 21632419 |
| photoreceptor processing speed and input resistance changes during light adaptation correlate with spectral class in the bumblebee, bombus impatiens. | colour vision depends on comparison of signals from photoreceptors with different spectral sensitivities. however, response properties of photoreceptor cells may differ in ways other than spectral tuning. in insects, for example, broadband photoreceptors, with a major sensitivity peak in the green region of the spectrum (>500 nm), drive fast visual processes, which are largely blind to chromatic signals from more narrowly-tuned photoreceptors with peak sensitivities in the blue and uv regions of ... | 2011 | 22046251 |
| Performance of Apis mellifera, Bombus impatiens, and Peponapis pruinosa (Hymenoptera: Apidae) as pollinators of pumpkin. | Pollination services of pumpkin, Cucurbita pepo L., provided by the European honey bee, Apis mellifera L., were compared with two native bee species, the common eastern bumble bee, Bombus impatiens (Cresson), and Peponapis pruinosa Say, in New York from 2008 to 2010. Performance of each species was determined by comparing single-visit pollen deposition, percentage of visits that contacted the stigma, flower-handling time, fruit and seed set, and fruit weight per number of visits. Fruit yield fro ... | 2011 | 21882677 |
| Patterns of range-wide genetic variation in six North American bumble bee (Apidae: Bombus) species. | The increasing evidence for population declines in bumble bee (Bombus) species worldwide has accelerated research efforts to explain losses in these important pollinators. In North America, a number of once widespread Bombus species have suffered serious reductions in range and abundance, although other species remain healthy. To examine whether declining and stable species exhibit different levels of genetic diversity or population fragmentation, we used microsatellite markers to genotype popul ... | 2011 | 22035452 |
| interspecific geographic distribution and variation of the pathogens nosema bombi and crithidia species in united states bumble bee populations. | several bumble bee (bombus) species in north america have undergone range reductions and rapid declines in relative abundance. pathogens have been suggested as causal factors, however, baseline data on pathogen distributions in a large number of bumble bee species have not been available to test this hypothesis. in a nationwide survey of the us, nearly 10,000 specimens of 36 bumble bee species collected at 284 sites were evaluated for the presence and prevalence of two known bombus pathogens, th ... | 2011 | 22119631 |
| Percent lipid is associated with body size but not task in the bumble bee Bombus impatiens. | In some group-living organisms, labor is divided among individuals. This allocation to particular tasks is frequently stable and predicted by individual physiology. Social insects are excellent model organisms in which to investigate the interplay between physiology and individual behavior, as division of labor is an important feature within colonies, and individual physiology varies among the highly related individuals of the colony. Previous studies have investigated what factors are important ... | 2011 | 21847618 |
| influence of honey bee, apis mellifera, hives and field size on foraging activity of native bee species in pumpkin fields. | the purpose of this study was to identify bee species active in pumpkin fields in new york and to estimate their potential as pollinators by examining their foraging activity. in addition, we examined whether foraging activity was affected by either the addition of hives of the honey bee, apis mellifera l., or by field size. thirty-five pumpkin (cucurbita spp.) fields ranging from 0.6 to 26.3 ha, 12 supplemented with a. mellifera hives and 23 not supplemented, were sampled during peak flowering ... | 2011 | 22251726 |
| comparison of the efficiency of the bumble bees bombus impatiens and bombus ephippiatus (hymenoptera: apidae) as pollinators of tomato in greenhouses. | experiments were conducted in a commercial tomato, solanum lycopersicum l. (solanaceae) greenhouse to compare the relative foraging effort and efficiency of two bumble bee species: bombus impatiens cresson, a species from northeastern north america, commercially reared and used for pollination in mexico; and b. ephippiatus say, a native species of mexico and central america. b. ephippiatus was as efficient in pollination of tomatoes as b. impatiens, as indicated by all variables of fruit quality ... | 2012 | 23356048 |
| different toxic and hormetic responses of bombus impatiens to beauveria bassiana, bacillus subtilis and spirotetramat. | pollinator exposure to pesticides is a concern in agricultural systems that depend on pollinators for crop production. however, not all pesticides elicit toxic effects, and response to a pesticide will vary depending on dose and exposure route. the effects of biopesticide formulations of bacillus subtilis and beauveria bassiana and of the tetramic acid insecticide spirotetramat on the common eastern bumblebee, bombus impatiens, were evaluated. microcolonies of bees were exposed to field-rate or ... | 2012 | 23281229 |
| detoxification and stress response genes expressed in a western north american bumble bee, bombus huntii (hymenoptera: apidae). | the hunt bumble bee (bombus huntii greene, hymenoptera: apidae) is a holometabolous, social insect important as a pollinator in natural and agricultural ecosystems in western north america. bumble bees spend a significant amount of time foraging on a wide variety of flowering plants, and this activity exposes them to both plant toxins and pesticides, posing a threat to individual and colony survival. little is known about what detoxification pathways are active in bumble bees, how the expression ... | 2013 | 24330608 |
| 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 |
| possible synergistic effects of thymol and nicotine against crithidia bombi parasitism in bumble bees. | floral nectar contains secondary compounds with antimicrobial properties that can affect not only plant-pollinator interactions, but also interactions between pollinators and their parasites. although recent work has shown that consumption of plant secondary compounds can reduce pollinator parasite loads, little is known about the effects of dosage or compound combinations. we used the generalist pollinator bombus impatiens and its obligate gut parasite crithidia bombi to study the effects of ne ... | 2015 | 26657643 |
| testing dose-dependent effects of the nectar alkaloid anabasine on trypanosome parasite loads in adult bumble bees. | the impact of consuming biologically active compounds is often dose-dependent, where small quantities can be medicinal while larger doses are toxic. the consumption of plant secondary compounds can be toxic to herbivores in large doses, but can also improve survival in parasitized herbivores. in addition, recent studies have found that consuming nectar secondary compounds may decrease parasite loads in pollinators. however, the effect of compound dose on bee survival and parasite loads has not b ... | 2015 | 26545106 |
| variable effects of nicotine, anabasine, and their interactions on parasitized bumble bees. | secondary metabolites in floral nectar have been shown to reduce parasite load in two common bumble bee species. previous studies on the effects of nectar secondary metabolites on parasitized bees have focused on single compounds in isolation; however, in nature, bees are simultaneously exposed to multiple compounds. we tested for interactions between the effects of two alkaloids found in the nectar of nicotiana spp. plants, nicotine and anabasine, on parasite load and mortality in bumble bees ( ... | 2015 | 26998225 |
| managed bumble bees (bombus impatiens) (hymenoptera: apidae) caged with blueberry bushes at high density did not increase fruit set or fruit weight compared to open pollination. | highbush blueberry (vaccinium corymbosum l.) is an important crop grown throughout florida. currently, most blueberry growers use honey bees (apis mellifera l.) to provide pollination services for highbush blueberries even though bumble bees (bombus spp.) have been shown to be more efficient at pollinating blueberries on a per bee basis. in general, contribution of bumble bees to the pollination of commercial highbush blueberries in florida is unknown. herein, we determined if managed bumble bee ... | 2017 | 28334127 |
| bee community of commercial potato fields in michigan and bombus impatiens visitation to neonicotinoid-treated potato plants. | we conducted a bee survey in neonicotinoid-treated commercial potato fields using bowl and vane traps in the 2016 growing season. traps were placed outside the fields, at the field edges, and 10 and 30 m into the fields. we collected 756 bees representing 58 species, with lasioglossum spp. comprising 73% of all captured bees. we found seven bombus spp., of which b. impatiens was the only known visitor of potato flowers in our region. the majority of the bees (68%) were collected at the field edg ... | 2017 | 28282931 |
| foraging in an unsteady world: bumblebee flight performance in field-realistic turbulence. | natural environments are characterized by variable wind that can pose significant challenges for flying animals and robots. however, our understanding of the flow conditions that animals experience outdoors and how these impact flight performance remains limited. here, we combine laboratory and field experiments to characterize wind conditions encountered by foraging bumblebees in outdoor environments and test the effects of these conditions on flight. we used radio-frequency tags to track forag ... | 2017 | 28163878 |
| 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 |
| food limitation affects parasite load and survival of bombus impatiens (hymenoptera: apidae) infected with crithidia (trypanosomatida: trypanosomatidae). | bumble bees (genus bombus) are globally important insect pollinators, and several species have experienced marked declines in recent years. both nutritional limitation and pathogens may have contributed to these declines. while each of these factors may be individually important, there may also be synergisms where nutritional stress could decrease pathogen resistance. understanding interactions between bumble bees, their parasites, and food availability may provide new insight into the causes of ... | 2016 | 27523087 |
| comparison of buckwheat, red clover, and purple tansy as potential surrogate plants for use in semi-field pesticide risk assessments with bombus impatiens. | background. bumble bees (bombus spp.) are important wild and managed pollinators. there is increased interest in incorporating data on bumble bees into risk assessments for pesticides, but standardized methods for assessing hazards of pesticides in semi-field and field settings have not yet been established for bumble bees. during semi-field studies, colonies are caged with pesticide-treated flowering surrogate plants, which must be attractive to foragers to ensure colony exposure to the test co ... | 2016 | 27478712 |
| wind alters landing dynamics in bumblebees. | landing is an important but understudied behavior that flying animals must perform constantly. in still air, insects decelerate smoothly prior to landing by employing the relatively simple strategy of maintaining a constant rate of image expansion during their approach. however, it is unclear whether insects employ this strategy when faced with challenging flight environments. here, we tested the effects of wind on bumblebees (bombus impatiens) landing on flowers. we find that bees' approach pat ... | 2016 | 27436135 |
| proline as a fuel for insect flight: enhancing carbohydrate oxidation in hymenopterans. | bees are thought to be strict users of carbohydrates as metabolic fuel for flight. many insects, however, have the ability to oxidize the amino acid proline at a high rate, which is a unique feature of this group of animals. the presence of proline in the haemolymph of bees and in the nectar of plants led to the hypothesis that plants may produce proline as a metabolic reward for pollinators. we investigated flight muscle metabolism of hymenopteran species using high-resolution respirometry perf ... | 2016 | 27412285 |
| macronutrient ratios in pollen shape bumble bee (bombus impatiens) foraging strategies and floral preferences. | to fuel their activities and rear their offspring, foraging bees must obtain a sufficient quality and quantity of nutritional resources from a diverse plant community. pollen is the primary source of proteins and lipids for bees, and the concentrations of these nutrients in pollen can vary widely among host-plant species. therefore we hypothesized that foraging decisions of bumble bees are driven by both the protein and lipid content of pollen. by successively reducing environmental and floral c ... | 2016 | 27357683 |
| foraging bumble bees weigh the reliability of personal and social information. | many animals, including insects, make decisions using both personally gathered information and social information derived from the behavior of other, usually conspecific, individuals [1]. moreover, animals adjust use of social versus personal information appropriately under a variety of experimental conditions [2-5]. an important factor in how information is used is the information's reliability, that is, how consistently the information is correlated with something of relevance in the environme ... | 2016 | 27133871 |
| exposure effects on the productivity of commercial bombus impatiens (hymenoptera: apidae) quads during bloom in watermelon fields. | in light of population declines of honey bees (apis mellifera l.), research has refocused attention on alternative pollinators and their potential to fulfill pollination services within economically important agricultural crops. bumble bees are one such alternative, and within the past 20 yr, these pollinators have been reared and sold as commercial pollinators. investigation into their use has been limited and more research is needed to improve pollinator effectiveness in field settings. quad p ... | 2015 | 26470323 |
| effect of number of bombus impatiens (hymenoptera: apidae) visits on eggplant yield. | eggplant (solanum melongena l.) is a crop with perfect flowers capable of self-pollination. insect pollination enhances fruit set, but little is known about how pollination success varies by number of visits from bumble bees. to quantify the efficiency of bumble bees at pollinating eggplants, we allowed 1, 2, 6, and 12 bumble bees (bombus impatiens cresson) to visit eggplant flowers and compared percentage of flowers that set fruit, fruit weight, and seed set after 3 wk. we compared yield from t ... | 2015 | 26470277 |
| bombus huntii, bombus impatiens, and bombus vosnesenskii (hymenoptera: apidae) pollinate greenhouse-grown tomatoes in western north america. | bumble bees (bombus) are the primary pollinators of tomatoes grown in greenhouses and can significantly increase fruit weight compared with tomatoes that receive no supplemental pollination. more than a million colonies are sold worldwide annually to meet pollination needs. due to mounting concerns over the transportation of bumble bees outside of their native ranges, several species native to western north american are currently being investigated as potential commercial pollinators. here, two ... | 2015 | 26470206 |
| colonies of bumble bees (bombus impatiens) produce fewer workers, less bee biomass, and have smaller mother queens following fungicide exposure. | bees provide vital pollination services to the majority of flowering plants in both natural and agricultural systems. unfortunately, both native and managed bee populations are experiencing declines, threatening the persistence of these plants and crops. agricultural chemicals are one possible culprit contributing to bee declines. even fungicides, generally considered safe for bees, have been shown to disrupt honey bee development and impair bumble bee behavior. little is known, however, how fun ... | 2015 | 26463198 |
| increased acetylcholinesterase expression in bumble bees during neonicotinoid-coated corn sowing. | while honey bee exposure to systemic insecticides has received much attention, impacts on wild pollinators have not been as widely studied. neonicotinoids have been shown to increase acetylcholinesterase (ache) activity in honey bees at sublethal doses. high ache levels may therefore act as a biomarker of exposure to neonicotinoids. this two-year study focused on establishing whether bumble bees living and foraging in agricultural areas using neonicotinoid crop protection show early biochemical ... | 2015 | 26223214 |
| a simple model for pollen-parent fecundity distributions in bee-pollinated forage legume polycrosses. | a simple weibull distribution based empirical model that predicts pollen-parent fecundity distributions based on polycross size alone has been developed in outbred forage legume species for incorporation into quantitative genetic theory. random mating or panmixis is a fundamental assumption in quantitative genetic theory. random mating is sometimes thought to occur in actual fact, although a large body of empirical work shows that this is often not the case in nature. models have been developed ... | 2015 | 26105686 |
| variation in reward quality and pollinator attraction: the consumer does not always get it right. | nearly all bees rely on pollen as the sole protein source for the development of their larvae. the central importance of pollen for the bee life cycle should exert strong selection on their ability to locate the most rewarding sources of pollen. despite this importance, very few studies have examined the influence of intraspecific variation in pollen rewards on the foraging decisions of bees. previous studies have demonstrated that inbreeding reduces viability and hence protein content in mimulu ... | 2015 | 25858692 |
| an ultraviolet floral polymorphism associated with life history drives pollinator discrimination in mimulus guttatus. | • | 2015 | 25784473 |
| evaluating pollination deficits in pumpkin production in new york. | potential decreases in crop yield from reductions in bee-mediated pollination services threaten food production demands of a growing population. many fruit and vegetable growers supplement their fields with bee colonies during crop bloom. the extent to which crop production requires supplementary pollination services beyond those provided by wild bees is not well documented. pumpkin, cucurbita pepo l., requires bee-mediated pollination for fruit development. previous research identified the comm ... | 2014 | 25198126 |
| a field study examining the effects of exposure to neonicotinoid seed-treated corn on commercial bumble bee colonies. | neonicotinoid insecticides have been studied as possible contributors to bumble bee declines in north america and europe. this has potential significance in corn agro-ecosystems since this crop is frequently treated with neonicotinoids and dominates much of the agricultural landscape in north america and europe where bumble bees and other pollinators are commonplace. we conducted an experiment where commercial bumble bee (bombus impatiens) hives were placed during pollen shed next to corn (zea m ... | 2014 | 25194943 |
| inbreeding in mimulus guttatus reduces visitation by bumble bee pollinators. | inbreeding in plants typically reduces individual fitness but may also alter ecological interactions. this study examined the effect of inbreeding in the mixed-mating annual mimulus guttatus on visitation by pollinators (bombus impatiens) in greenhouse experiments. previous studies of m. guttatus have shown that inbreeding reduced corolla size, flower number, and pollen quantity and quality. using controlled crosses, we produced inbred and outbred families from three different m. guttatus popula ... | 2014 | 25036035 |
| the innate responses of bumble bees to flower patterns: separating the nectar guide from the nectary changes bee movements and search time. | nectar guides can enhance pollinator efficiency and plant fitness by allowing pollinators to more rapidly find and remember the location of floral nectar. we tested if a radiating nectar guide around a nectary would enhance the ability of naïve bumble bee foragers to find nectar. most experiments that test nectar guide efficacy, specifically radiating linear guides, have used guides positioned around the center of a radially symmetric flower, where nectaries are often found. however, the flower ... | 2014 | 24879351 |
| genomic features of a bumble bee symbiont reflect its host environment. | here, we report the genome of one gammaproteobacterial member of the gut microbiota, for which we propose the name "candidatus schmidhempelia bombi," that was inadvertently sequenced alongside the genome of its host, the bumble bee, bombus impatiens. this symbiont is a member of the recently described bacterial order orbales, which has been collected from the guts of diverse insect species; however, "ca. schmidhempelia" has been identified exclusively with bumble bees. metabolic reconstruction r ... | 2014 | 24747890 |
| how images may or may not represent flowers: picture-object correspondence in bumblebees (bombus impatiens)? | studies of bee cognition frequently use two-dimensional stimuli referred to as floral patterns, and yet how bees perceive pictorial representations is not known. an investigation of bumblebee (bombus impatiens) picture-object correspondence was undertaken according to the theory of fagot et al. (picture perception in animals. psychology press ltd, east sussex, pp 295-320, 2000) that pictures and objects may be confused, perceived as independent or equivalent. in three experiments, bumblebees wer ... | 2014 | 24531905 |
| impacts of a neonicotinoid, neonicotinoid-pyrethroid premix, and anthranilic diamide insecticide on four species of turf-inhabiting beneficial insects. | many turf managers prefer to control foliage- and root-feeding pests with the same application, so-called multiple-targeting, using a single broad-spectrum insecticide or a premix product containing two or more active ingredients. we compared the impact of a neonicotinoid (clothianidin), a premix (clothianidin + bifenthrin), and an anthranilic diamide (chlorantraniliprole), the main insecticide classes used for multiple targeting, on four species of beneficial insects: harpalus pennsylvanicus, a ... | 2014 | 24493235 |
| ubx promotes corbicular development in apis mellifera. | the key morphological feature that distinguishes corbiculate bees from other members of the apidae family is the presence of the corbicula (pollen basket) on the tibial segment of hind legs. here, we show that in the honeybee (apis mellifera), the depletion of the gene ultrabithorax (ubx) by rnai transforms the corbicula from a smooth, bristle-free concave structure to one covered with bristles. this is accompanied by a reduction of the pollen press, which is located on the basitarsus and used f ... | 2014 | 24478202 |
| revisiting comparisons of genetic diversity in stable and declining species: assessing genome-wide polymorphism in north american bumble bees using rad sequencing. | genetic variation is of key importance for a species' evolutionary potential, and its estimation is a major component of conservation studies. new dna sequencing technologies have enabled the analysis of large portions of the genome in nonmodel species, promising highly accurate estimates of such population genetic parameters. restriction site-associated dna sequencing (radseq) is used to analyse thousands of variants in the bumble bee species bombus impatiens, which is common, and bombus pensyl ... | 2014 | 24351120 |
| plasticity of the worker bumblebee brain in relation to age and rearing environment. | the environment experienced during development can dramatically affect the brain, with possible implications for sensory processing, learning, and memory. although the effects of single sensory modalities on brain development have been repeatedly explored, the additive or interactive effects of multiple modalities have been less thoroughly investigated. we asked how experience with multisensory stimuli affected brain development in the bumblebee bombus impatiens. first, to establish the timeline ... | 2013 | 24281415 |
| supporting crop pollinators with floral resources: network-based phenological matching. | the production of diverse and affordable agricultural crop species depends on pollination services provided by bees. indeed, the proportion of pollinator-dependent crops is increasing globally. agriculture relies heavily on the domesticated honeybee; the services provided by this single species are under threat and becoming increasingly costly. importantly, the free pollination services provided by diverse wild bee communities have been shown to be sufficient for high agricultural yields in some ... | 2013 | 24101999 |
| pollination services provided by bees in pumpkin fields supplemented with either apis mellifera or bombus impatiens or not supplemented. | pollinators provide an important service in many crops. managed honey bees (apis mellifera l.) are used to supplement pollination services provided by wild bees with the assumption that they will enhance pollination, fruit set and crop yield beyond the levels provided by the wild bees. recent declines in managed honey bee populations have stimulated interest in finding alternative managed pollinators to service crops. in the eastern u.s., managed hives of the native common eastern bumble bee (bo ... | 2013 | 23894544 |
| assessing insecticide hazard to bumble bees foraging on flowering weeds in treated lawns. | maintaining bee-friendly habitats in cities and suburbs can help conserve the vital pollination services of declining bee populations. despite label precautions not to apply them to blooming plants, neonicotinoids and other residual systemic insecticides may be applied for preventive control of lawn insect pests when spring-flowering weeds are present. dietary exposure to neonicotinoids adversely affects bees, but the extent of hazard from field usage is controversial. we exposed colonies of the ... | 2013 | 23776667 |
| individual lifetime pollen and nectar foraging preferences in bumble bees. | foraging specialization plays an important role in the ability of social insects to efficiently allocate labor. however, relatively little is known about the degree to which individual bumble bees specialize on collecting nectar or pollen, when such preferences manifest, and if individuals can alter their foraging preferences in response to changes in the colony workforce. using bombus impatiens, we monitored all foraging visits made by every bee in multiple colonies and showed that individual f ... | 2012 | 22965265 |
| size-related variation in protein abundance in the brain and abdominal tissue of bumble bee workers. | female bumble bee workers of the same species often show a profound body size variation that is linked to a division of labour. large individuals are more likely to forage whereas small individuals are more likely to perform in-nest activities. a higher sensory sensitivity, stronger circadian rhythms as well as better learning and memory performances appear to better equip large individuals for outdoor activities compared to their smaller siblings. the molecular mechanisms underlying worker func ... | 2012 | 22568679 |
| ontogeny of worker body size distribution in bumble bee (bombus impatiens) colonies. | bumble bees exhibit worker size polymorphisms; highly related workers within a colony may vary up to 10-fold in body mass. as size variation is an important life history feature in bumble bees, the distribution of body sizes within the colony and how it fluctuates over the colony cycle were analysed.ten commercially purchased colonies of bombus impatiens (cresson) were reared in ad libitum conditions. the size of all workers present and newly emerging workers (callows) was recorded each week.the ... | 2010 | 26023250 |
| species differences in bumblebee immune response predict developmental success of a parasitoid fly. | endoparasitoids develop inside the body of a host organism and, if successful, eventually kill their host in order to reach maturity. host species can vary in their suitability for a developing endoparasitoid; in particular, the host immune response, which can suppress egg hatching and larval development, has been hypothesized to be one of the most important determinants of parasitoid host range. in this study, we investigated whether three bumblebee host species (bombus bimaculatus, bombus gris ... | 2015 | 25795253 |
| chronic exposure to a neonicotinoid increases expression of antimicrobial peptide genes in the bumblebee bombus impatiens. | bumblebees are important pollinators in wild and agricultural settings. in recent decades pollinator declines have been linked to the effects of increased pesticide use and the spread of disease. synergy between these factors has been suggested, but no physiological mechanism has been identified. this study examines the connection between neonicotinoid exposure and innate immune function in the bumblebee bombus impatiens, which is an important wild and commercial pollinator in eastern north amer ... | 2017 | 28322347 |
| consequences of toxic secondary compounds in nectar for mutualist bees and antagonist butterflies. | attraction of mutualists and defense against antagonists are critical challenges for most organisms and can be especially acute for plants with pollinating and non-pollinating flower visitors. secondary compounds in flowers have been hypothesized to adaptively mediate attraction of mutualists and defense against antagonists, but this hypothesis has rarely been tested. the tissues of milkweeds (asclepias spp.) contain toxic cardenolides that have long been studied as chemical defenses against her ... | 2016 | 27859127 |
| chemical communication is not sufficient to explain reproductive inhibition in the bumblebee bombus impatiens. | reproductive division of labour is a hallmark of eusociality, but disentangling the underlying proximate mechanisms can be challenging. in bumblebees, workers isolated from the queen can activate their ovaries and lay haploid, male eggs. we investigated if volatile, contact, visual or behavioural cues produced by the queen or brood mediate reproductive dominance in bombus impatiens. exposure to queen-produced volatiles, brood-produced volatiles and direct contact with pupae did not reduce worker ... | 2016 | 27853577 |