Find research datasets worth reusing

Figs 14‒16 in Widespread polytypic species or complexes of local species? Revising bumblebees of the subgenus Melanobombus world-wide (Hymenoptera, Apidae, Bombus)

Figs 14‒16. Maps of sequenced samples as in Figs 12–13. 14. The tanguticus-group and the lapidarius- group. 15. The sichelii-group. 16. The keriensis-group.

Figs 181‒189 in Widespread polytypic species or complexes of local species? Revising bumblebees of the subgenus Melanobombus world-wide (Hymenoptera, Apidae, Bombus)

Figs 181‒189. Morphology of the male genitalia for species of the subgenus Melanobombus von Dalla Torre, 1880 from the dorsal aspect, anterior at the bottom of the image, posterior at the top. 181. Bombus eximius Smith, 1852, China-Guangxi. 182. B. rufipes Lepeletier, 1835, IndonesiaJava. 183. B. festivus Smith, 1861, Nepal. 184. B. simillimus Smith, 1852, India-Himachal Pradesh. 185. B. miniatus Bingham, 1897, Bhutan. 186. B. eurythorax Wang, 1982 stat. rev., India-Kashmir. 187. B. prshewalskyi Morawitz, 1880 stat. rev., China-Sichuan. 188. B. rufofasciatus Smith, 1852, IndiaKashmir. 189. B. richardsiellus (Tkalců, 1968), Burma (left volsella distal part missing). Scale bars = 1 mm.

Figs 64–102 in Widespread polytypic species or complexes of local species? Revising bumblebees of the subgenus Melanobombus world-wide (Hymenoptera, Apidae, Bombus)

Figs 64–102. Simplified diagrams for the colour patterns of the hair on the dorsum for the species from the integrative analysis. The dorsum is divided into regions, each of which shows only the predominant or most apparent colour for that region using a simplified colour palette, with olive indicating a mixture of black and yellow hair, and grey indicating a mixture of black and white hair. The rufofasciatus-group. 64. Queen, China-Yunnan. 65. Queen, China-Sichuan. 66. Worker, China-Xizang. 67. Worker, ChinaXizang. 68. Worker, China-Gansu. 69. Male, China-Yunnan. 70. Male, China-Xizang. 71. Queen, IndiaKashmir. 72. Queen, India-Kashmir. 73. Queen, Pakistan. 74. Worker, India-Kashmir. 75. Worker, IndiaKashmir. 76. Male, Pakistan. 77. Male, India-Kashmir. 78. Queen, Burma. 79. Worker, Burma. 80. Worker, China-Xizang. 81. Worker, China-Xizang. 82. Male, Burma. 83. Queen, China-Sichuan. 84. Worker, China-Sichuan. 85. Worker, China-Sichuan. 86. Worker, China-Sichuan. 87. Worker, China-Sichuan. 88. Worker, China-Xizang. 89. Male, China-Sichuan. 90. Male, China-Sichuan. 91. Queen, China-Beijing. 92. Queen, China-Beijing. 93. Worker, China-Shanxi. 94. Worker, China-Beijing. 95. Worker, ChinaBeijing. 96. Male, China-Beijing. 97. Male, China-Beijing. 98. Queen, China-Taiwan. 99. Worker, ChinaTaiwan. 100. Worker, China-Taiwan. 101. Worker, China-Taiwan. 102. Male, China-Taiwan.

opencc-zeroSep 2020View details →

Data from: Assessing species richness trends: declines of bees and bumblebees in the Netherlands since 1945.

Estimating and predicting temporal trends in species richness is of general importance, but notably difficult because detection probabilities of species are imperfect and many datasets were collected in an opportunistic manner. We need to improve our capabilities to assess richness trends using datasets collected in unstandardized procedures with potential collection bias. Two methods are proposed and applied to estimate richness change, which both incorporate models for sampling effects and detection probability: (1) non-linear species accumulation curves with an error variance model and (2) Pradel capture-recapture models. The methods are used to assess nationwide temporal trends (1945-2018) in the species richness of wild bees in the Netherlands. Previously, a decelerating decline in wild bee species richness was inferred for part of this dataset. Among the species accumulation curves, those with non-constant changes in species richness are preferred. However, when analysing data subsets, constant changes became selected for non-Bombus bees (for samples in collections) and bumblebees (for spatial grid cells sampled in three periods). Smaller richness declines are predicted for non-Bombus bees than bumblebees. However, when relative losses are calculated from confidence intervals limits, they overlap and touch zero loss. Capture-recapture analysis applied to species encounter histories infers a constant colonization rate per year and constant local species survival for bumblebees and other bees. This approach predicts a 6% reduction in non-Bombus species richness from 1945 to 2018 and a significant 19% reduction for bumblebees. Statistical modelling to detect species richness time trends should be systematically complemented with model checking and simulations to interpret the results. Data inspection, assessing model selection bias and comparisons of trends in data subsets were essential model checking strategies in this analysis. Opportunistic data will not satisfy the assumptions of most models and this should be kept in mind throughout.

opencc-zeroOct 2020View details →

Supplementary material 1 from: Ghisbain G, Williams PH, Michez D, Branstetter MG, Rasmont P (2020) Contribution to the knowledge of the bumblebee fauna of Afghanistan (Hymenoptera, Apidae, Bombus Latreille). ZooKeys 973: 69-87. https://doi.org/10.3897/zookeys.973.54796

Table S1. Bumblebee records examined in the present study

Figure 2 from: Ghisbain G, Williams PH, Michez D, Branstetter MG, Rasmont P (2020) Contribution to the knowledge of the bumblebee fauna of Afghanistan (Hymenoptera, Apidae, Bombus Latreille). ZooKeys 973: 69-87. https://doi.org/10.3897/zookeys.973.54796

Figure 2 Some of the Afghan bumblebee taxa examined as part of this study. ABombus (Subterraneobombus) melanurusBB. (Sibiricobombus) morawitziCB. (Melanobombus) semenovianusDB. (Melanobombus) keriensiss. s.EB. (Sibiricobombus) obtususFB. (Sibiricobombus) asiaticus. Photograph credits P. Rasmont.

Figure 1 from: Ghisbain G, Williams PH, Michez D, Branstetter MG, Rasmont P (2020) Contribution to the knowledge of the bumblebee fauna of Afghanistan (Hymenoptera, Apidae, Bombus Latreille). ZooKeys 973: 69-87. https://doi.org/10.3897/zookeys.973.54796

Figure 1 Map of Afghanistan and neighboring regions depicting the sampling examined as part of this study. Numbers correspond to the following locations: 1) Kotal-e-Asgharat; 2) Kotal-e-Narges, D-e-Godar; 3) Ghorghori-e-Panjao, Gaukhana; 4) Pagmangebirge; 5) Salang-Nord, vic. Khindjan / Salang-Paß; 6) Andarab; 7) upper Lezdi valley; 8) Lezdi; 9) Chodja-Mahomed [Kwaja Muhammed]; 10) Shiva-See; 11) Bala Kuran; 12) Kotal-e-Wazir; 13) Darrah-e-Istmotsh 14) Issiktal [Quellflur in Artemisia-Chenopodiensteppe]; 15) Ptukh; 16) Issik; 17) Ahmad Diwana (Baba); 18) Bashgal river; 19) Kamdesh, near Suingal/Shkurigal confluence; 20) Badakshan, Anjuman Pass; 21) Dar.-e-Pandjshir, Kotal-e-Tal; 22) Sarobi; 23) Safed Koh, Kotkai. GPS coordinates and altitude of these sites are given in Table 1 and in the associated database (Suppl. material 1).

opencc-zeroDec 2016View details →

Data from: General and species-specific impacts of a neonicotinoid insecticide on the ovary development and feeding of wild bumblebee queens

Bumblebees are essential pollinators of crops and wild plants, but are in decline across the globe. Neonicotinoid pesticides have been implicated as a potential driver of these declines, but most of our evidence base comes from studies of a single species. There is an urgent need to understand whether such results can be generalized across a range of species. Here, we present results of a laboratory experiment testing the impacts of field-relevant doses (1.87–5.32 ppb) of the neonicotinoid thiamethoxam on spring-caught wild queens of four bumblebee species: Bombus terrestris, B. lucorum, B. pratorum and B. pascuorum. Two weeks of exposure to the higher concentration of thiamethoxam caused a reduction in feeding in two out of four species, suggesting species-specific anti-feedant, repellency or toxicity effects. The higher level of thiamethoxam exposure resulted in a reduction in the average length of terminal oocytes in queens of all four species. In addition to providing the first evidence for general effects of neonicotinoids on ovary development in multiple species of wild bumblebee queens, the discovery of species-specific effects on feeding has significant implications for current practices and policy for pesticide risk assessment and use.

Data from: Foraging bumblebees acquire a preference for neonicotinoid-treated food with prolonged exposure

Social bees represent an important group of pollinating insects but can be exposed to potentially harmful pesticides when foraging on treated or contaminated flowering plants. To investigate if such exposure is detrimental to bees, many studies have exclusively fed individuals with pesticide spiked food, informing us about the hazard but not necessarily the risk of exposure. Whilst such studies are important to establish the physiological and behavioural effects on individuals they do not consider the possibility that exposure may change over time. For example, many pesticide assays exclude potential behavioural adaptations, such as a rejection of harmful compounds by choosing to feed on an uncontaminated food source, which would behaviourally lower the risk of exposure. Here we conducted an experiment over 10 days in which bumblebees forage on an array of sucrose feeders containing a range of concentrations (0, 2 & 11 parts per billion) of the neonicotinoid pesticide thiamethoxam. We more closely mimic pesticide exposure in the wild by allowing foraging bees to experience i) a range of pesticide concentrations across a chronic exposure period, ii) repeated interactions with the pesticide, and iii) allowing foraging bees to retain the social cues associated with foraging by using whole colonies. We found that the proportion of visits to pesticide-laced feeders increased over time, resulting in the consumption of more pesticide-laced sucrose. After changing the spatial position of each feeder, foragers continued to preferentially visit the pesticide-laced food, indicating that workers can detect thiamethoxam and alter their behaviour to continue feeding from it. The increasing preference for consuming the neonicotinoid treated food, therefore increases the risk of exposure for the colony during prolonged pesticide exposure. Our results highlight the need to incorporate attractiveness of field relevant concentrations of pesticides to foraging bees (and other insect p

opencc-zeroDec 2013View details →

Data from: Chronic impairment of bumblebee natural foraging behaviour induced by sublethal pesticide exposure

1. Insect pollination is a vital ecosystem service that maintains biodiversity and sustains agricultural crop yields. Social bees are essential insect pollinators so it is concerning that their populations are in global decline. 2. Although pesticide exposure has been implicated as a possible cause for bee declines, we currently have a limited understanding of the risk these chemicals pose. Whilst environmental exposure to pesticides typically has non-lethal effects on individual bees, recent reports suggest that sublethal exposure can affect important behavioural traits such as foraging. However, at present we know comparatively little about how natural foraging behaviour is impaired and the relative impacts of acute and chronic effects. 3. Using Radio Frequency Identification (RFID) tagging technology we examined how the day-to-day foraging patterns of bumblebees (Bombus terrestris) were affected when exposed to either a neonicotinoid (imidacloprid) and/or a pyrethroid (λ-cyhalothrin) independently and in combination over a four week period. This is the first study to provide data on the impacts of combined and individual pesticide exposure on the temporal dynamics of foraging behaviour in the field over a prolonged period of time. 4. Our results show that neonicotinoid exposure has both acute and chronic effects on overall foraging activity. While foragers from control colonies improved their pollen foraging performance as they gained experience, the performance of bees exposed to imidacloprid became worse: chronic behavioural impairment. We also found evidence suggesting that pesticide exposure can change forager preferences for the flower types from which they collect pollen. 5. Our findings highlight the importance of considering prolonged exposure (which happens in the field) when assessing the risk that pesticides pose to bees. The effects of chronic pesticide exposure could have serious detrimental consequences for both colony survival and also the pollination services provided by these essential insect pollinators.

Data from: Lower bumblebee colony reproductive success in agricultural compared to urban environments

Urbanisation represents a rapidly growing driver of land-use change. While it is clear that urbanisation impacts species abundance and diversity, direct effects of urban land-use on animal reproductive success are rarely documented. Here we show that urban land-use is linked to long-term colony reproductive output in a key pollinator. We reared colonies from wild-caught bumblebee (Bombus terrestris) queens, placed them at sites characterised by varying degrees of urbanisation from inner city to rural farmland, and monitored the production of sexual offspring across the entire colony cycle. Our land-use cluster analysis identified three site categories, and this categorization was a strong predictor of colony performance. Crucially, colonies in the two clusters characterized by urban development produced more sexual offspring than those in the cluster dominated by agricultural land. These colonies also reached higher peak size, had more food stores, encountered fewer parasite invasions and survived for longer. Our results show a link between urbanisation and bumblebee colony reproductive success, supporting the theory that urban areas provide a refuge for pollinator populations in an otherwise barren agricultural landscape.

opencc-zeroDec 2011View details →

Data from: Robustness of the outcome of adult bumblebee infection with a trypanosome parasite after varied parasite exposures during larval development

The outcome of defence by the invertebrate immunity has recently been shown to be more complex than previously thought. In particular, the outcome is affected by biotic and abiotic environmental variation, host genotype, parasite genotype, and their interaction. Knowledge of conditions under which environmental variation affects the outcome of an infection is one important question that relates to this complexity. We here use the model system of the bumblebee, Bombus terrestris infected by the trypanosome, Crithidia bombi, combined with a split-colony design to test the influence of the parasite environment during larval rearing on adult resistance. We find that genotype-specific interactions are maintained, and adult resistance is not influenced. This demonstrates that environmental dependence of bumblebee-trypanosome interactions is not ubiquitous, and yet unknown constraints will maintain standard co-evolutionary dynamics under such environmental deviations.

opencc-zeroDec 2016View details →

Data from: Colour as a backup for scent in the presence of olfactory noise: testing the efficacy backup hypothesis using bumblebees (Bombus terrestris)

The majority of floral displays simultaneously broadcast signals from multiple sensory modalities, but these multimodal displays come at both a metabolic cost and an increased conspicuousness to floral antagonists. Why then do plants invest in these costly multimodal displays? The efficacy backup hypothesis suggests that individual signal components act as a backup for others in the presence of environmental variability. Here, we test the efficacy backup hypothesis by investigating the ability of bumblebees to differentiate between sets of artificial flowers in the presence of either chemical interference or high wind speeds, both of which have the potential to impede the transmission of olfactory signals. We found that both chemical interference and high wind speeds negatively affected forager learning times, but these effects were mitigated in the presence of a visual signal component. Our results suggest that visual signals can act as a backup for olfactory signals in the presence of chemical interference and high wind speeds, and support the efficacy backup hypothesis as an explanation for the evolution of multimodal floral displays.

opencc-zeroDec 2015View details →

Data from: Copy-when-uncertain: bumblebees rely on social information when rewards are highly variable

To understand the relative benefits of social and personal information use in foraging decisions, we developed an agent-based model of social learning that predicts social information should be more adaptive where resources are highly variable and personal information where resources vary little. We tested our predictions with bumblebees and found that foragers relied more on social information when resources were variable than when they were not. We then investigated whether socially salient cues are used preferentially over non-social ones in variable environments. Although bees clearly used social cues in highly variable environments, under the same conditions they did not use non-social cues. These results suggest that bumblebees use a 'copy-when-uncertain' strategy.

opencc-zeroDec 2016View details →

Data from: Bumblebees show cognitive flexibility by improving on an observed complex behavior

We explored bees' behavioral flexibility in a task that required transporting a small ball to a defined location to gain a reward. Bees were pretrained to know the correct location of the ball. Subsequently, to obtain a reward, bees had to move a displaced ball to the defined location. Bees that observed demonstration of the technique from a live or model demonstrator learned the task more efficiently than did bees observing a "ghost" demonstration (ball moved via magnet) or without demonstration. Instead of copying demonstrators moving balls over long distances, observers solved the task more efficiently, using the ball positioned closest to the target, even if it was of a different color than the one previously observed. Such unprecedented cognitive flexibility hints that entirely novel behaviors could emerge relatively swiftly in species whose lifestyle demands advanced learning abilities, should relevant ecological pressures arise.

Data from: Effects of neonicotinoid insecticide exposure and monofloral diet on nest-founding bumblebee queens

Bumblebees are among the world's most important groups of pollinating insects in natural and agricultural ecosystems. Each spring, queen bumblebees emerge from overwintering and initiate new nests, which ultimately give rise to workers and new reproductives later in the season. Nest initiation and survival are thus key drivers of both bumblebee pollination services and population dynamics. We performed the first laboratory experiment with the model bumblebee species Bombus impatiens that explores how early nesting success is impacted by the effects of temporary or more sustained exposure to sublethal levels of a neonicotinoid-type insecticide (imidacloprid at 5 ppb in nectar) and by reliance on a monofloral pollen diet, two factors that have been previously implicated in bumblebee decline. We found that queens exhibited increased mortality and dramatically reduced activity levels when exposed to imidacloprid, as well as delayed nest initiation and lower brood numbers in the nest, but partially recovered from these effects when they only received early, temporary exposure. The effects of pollen diet on individual queen- and colony-level responses were overshadowed by effects of the insecticide, although a monofloral pollen diet alone was sufficient to negatively impact brood production. These findings speak to the sensitivity of queen bumblebees during the nest initiation phase of the colony cycle, with implications for how queens and their young nests are uniquely impacted by exposure to threats such as pesticide exposure and foraging habitat unsuitability.

opencc-zeroDec 2015View details →

Data from: Estimating resource preferences of a native bumblebee: the effects of availability and use-availability models on preference estimatess

Identifying resource preference is considered essential for developing targeted conservation plans but, for many species, questions remain about the best way to estimate preference. Resource preferences for bees are particularly difficult to determine as the resources they collect, nectar and pollen, are challenging to estimate availability and collection. Resources are traditionally measured at the flower or inflorescence level, but these measures of availability do not correspond to the resources actually used by bees. Additionally, it is unclear as to whether common models including availability are appropriate for bees which may target resources regardless of available quantities. Here we first compare two common hypotheses of resource use – the 'random use hypothesis' and the 'linear preferences hypothesis' – using three different measures of availability (pollen, flower and inflorescence) – to determine if one measure of availability was better for understanding bee pollen use. Next, the superior model using availability was compared to a novel model of bee pollen use the 'target use hypothesis'. This model assumes that bees target some resources regardless of how much of each resource is available (but assuming resources are present at a site), and thus models preference without availability data. Of the models including availability, the linear preference model using inflorescence availability best explained the pollen use data. This suggests that bumblebee pollen use is non-random and that cues to identify and locate resources (i.e. display size and quantity) may be more important than the quantity of the resource available (i.e. pollen availability). Additionally, in most cases the target use model explained the data equal to or better than the other models suggesting bee resource use may be better modeled without measured availability data compared to linear models. These results could be important for expanding resource use analysis of bees that are difficult to quantify availability.

opencc-zeroOct 2019View details →

Cross-activity of honeybee queen pheromones in bumblebees provides evidence for sensory exploitation

The evolutionary origin of queen pheromones, which regulate reproductive division of labor in insect societies, has been explained by two evolutionary scenarios: the sender-precursor hypothesis and the sensory exploitation hypothesis. These scenarios differ in terms of whether the signaling system was built on preadaptations on the part of either the sender queens or the receiver workers. While some social insect queen pheromones – such as cuticular hydrocarbons – were likely derived from ancestral fertility cues and evolved according to the former theory, the honeybee's queen mandibular pheromone (QMP) has been suggested to act directly on pre-existing gene-regulatory networks linked with reproduction. This is evidenced by the fact that QMP has been shown to also inhibit ovary activation in fruit flies, thereby implying exploitation of conserved physiological pathways. To verify whether QMP has similar effects on more closely related eusocial species, we here tested for QMP cross-activity in the bumblebee Bombus terrestris. Interestingly, we found that the non-native QMP blend significantly inhibited egg-laying in both worker and queen bumblebees and caused accompanying shifts in ovary activation. The native bumblebee queen pheromone pentacosane, by contrast, only inhibited the reproduction of the workers. Overall, these findings support the hypothesis that honeybee QMP likely evolved via a route of sensory exploitation. We argue that such exploitation could allow social insect queens to produce compounds that manipulate the workers to remain sterile, but that a major hurdle would be that the queens themselves would have to be immune to such compounds.

opencc-zeroDec 2012View details →

Data from: Ants and ant scent reduce bumblebee pollination of artificial flowers

Ants on flowers can disrupt pollination by consuming rewards or harassing pollinators, but it is difficult to disentangle the effects of these exploitative and interference forms of competition on pollinator behavior. Using highly rewarding and quickly replenishing artificial flowers that simulate male or female function, we allowed bumblebees (Bombus impatiens) to forage (1) on flowers with or without ants (Myrmica rubra) and (2) on flowers with or without ant scent cues. Bumblebees transferred significantly more pollen analogue both to and from ant-free flowers, demonstrating that interference competition with ants is sufficient to modify pollinator foraging behavior. Bees also removed significantly less pollen analogue from ant-scented flowers than from controls, making this the first study to show that bees can use ant scent to avoid harassment at flowers. Ant effects on pollinator behavior, possibly in addition to their effects on pollen viability, may contribute to the evolution of floral traits minimizing ant visitation.

Data from: Low dose of neonicotinoid insecticide reduces foraging motivation of bumblebees

Widespread use of neonicotinoid insecticides, such as imidacloprid, is often associated with diminishing populations of bees; this loss of pollinators presents a concern for food security and may cause unpredictable changes in ecological networks. However, little is known about the potential behavioral mechanisms behind the neonicotinoid-associated pollinator decline. We quantified the effects of low dose (1 ppb) imidacloprid exposure on the foraging behaviour of bumblebees (Bombus terrestris). Individual bumblebees were released into a flight arena containing three patches of robotic flowers whose colour (yellow, orange, blue) indicated whether the flower delivered a reward (sugar solution). Exposure to imidacloprid had no significant effect on measures of bumblebee physical performance (such as flight speed) or learning (identifying rewarding flowers). However, pesticide treated bumblebees had reduced foraging motivation compared with the control bumblebees, as they visited fewer robotic flowers, were slower to start foraging and did not visit all three flower colours as often. Neonicotinoid concentrations of 1 ppb, often reported in plant nectar near agricultural lands, can thus affect the foraging behaviour of bumblebees. Even without a notable impact on flight performance and learning, a reduction in foraging motivation could explain the poor performance of colonies of bumblebees exposed to neonicotinoids.