@article{TrinklKaluzaWallaceetal.2020,
  author    = {Trinkl, Moritz and Kaluza, Benjamin F. and Wallace, Helen and Heard, Tim A. and Keller, Alexander and Leonhardt, Sara D.},
  title     = {Floral Species Richness Correlates with Changes in the Nutritional Quality of Larval Diets in a Stingless Bee},
  series = {Insects},
  volume    = {11},
  journal   = {Insects},
  number    = {2},
  issn      = {2075-4450},
  doi       = {10.3390/insects11020125},
  url       = {http://nbn-resolving.de/urn:nbn:de:bvb:20-opus-200605},
  pages     = {125},
  year      = {2020},
  abstract  = {Bees need food of appropriate nutritional quality to maintain their metabolic functions. They largely obtain all required nutrients from floral resources, i.e., pollen and nectar. However, the diversity, composition and nutritional quality of floral resources varies with the surrounding environment and can be strongly altered in human-impacted habitats. We investigated whether differences in plant species richness as found in the surrounding environment correlated with variation in the floral diversity and nutritional quality of larval provisions (i.e., mixtures of pollen, nectar and salivary secretions) composed by the mass-provisioning stingless bee Tetragonula carbonaria (Apidae: Meliponini). We found that the floral diversity of larval provisions increased with increasing plant species richness. The sucrose and fat (total fatty acid) content and the proportion and concentration of the omega-6 fatty acid linoleic acid decreased, whereas the proportion of the omega-3 fatty acid linolenic acid increased with increasing plant species richness. Protein (total amino acid) content and amino acid composition did not change. The protein to fat (P:F) ratio, known to affect bee foraging, increased on average by more than 40\% from plantations to forests and gardens, while the omega-6:3 ratio, known to negatively affect cognitive performance, decreased with increasing plant species richness. Our results suggest that plant species richness may support T. carbonaria colonies by providing not only a continuous resource supply (as shown in a previous study), but also floral resources of high nutritional quality.},
  language  = {en}
}
@article{StrubeBlossBrownSpaetheetal.2015,
  author    = {Strube-Bloss, Martin F. and Brown, Austin and Spaethe, Johannes and Schmitt, Thomas and R{\"o}ssler, Wolfgang},
  title     = {Extracting the Behaviorally Relevant Stimulus: Unique Neural Representation of Farnesol, a Component of the Recruitment Pheromone of Bombus terrestris},
  series = {PLoS One},
  volume    = {10},
  journal   = {PLoS One},
  number    = {9},
  doi       = {10.1371/journal.pone.0137413},
  url       = {http://nbn-resolving.de/urn:nbn:de:bvb:20-opus-125875},
  pages     = {e0137413},
  year      = {2015},
  abstract  = {To trigger innate behavior, sensory neural networks are pre-tuned to extract biologically relevant stimuli. Many male-female or insect-plant interactions depend on this phenomenon. Especially communication among individuals within social groups depends on innate behaviors. One example is the efficient recruitment of nest mates by successful bumblebee foragers. Returning foragers release a recruitment pheromone in the nest while they perform a 'dance' behavior to activate unemployed nest mates. A major component of this pheromone is the sesquiterpenoid farnesol. How farnesol is processed and perceived by the olfactory system, has not yet been identified. It is much likely that processing farnesol involves an innate mechanism for the extraction of relevant information to trigger a fast and reliable behavioral response. To test this hypothesis, we used population response analyses of 100 antennal lobe (AL) neurons recorded in alive bumblebee workers under repeated stimulation with four behaviorally different, but chemically related odorants (geraniol, citronellol, citronellal and farnesol). The analysis identified a unique neural representation of the recruitment pheromone component compared to the other odorants that are predominantly emitted by flowers. The farnesol induced population activity in the AL allowed a reliable separation of farnesol from all other chemically related odor stimuli we tested. We conclude that the farnesol induced population activity may reflect a predetermined representation within the AL-neural network allowing efficient and fast extraction of a behaviorally relevant stimulus. Furthermore, the results show that population response analyses of multiple single AL-units may provide a powerful tool to identify distinct representations of behaviorally relevant odors.},
  language  = {en}
}
@article{RuedenauerRaubenheimerKessnerBeierleinetal.2020,
  author    = {Ruedenauer, Fabian A. and Raubenheimer, David and Kessner-Beierlein, Daniela and Grund-Mueller, Nils and Noack, Lisa and Spaethe, Johannes and Leonhardt, Sara D.},
  title     = {Best be(e) on low fat: linking nutrient perception, regulation and fitness},
  series = {Ecology Letters},
  volume    = {23},
  journal   = {Ecology Letters},
  number    = {3},
  doi       = {10.1111/ele.13454},
  url       = {http://nbn-resolving.de/urn:nbn:de:bvb:20-opus-208709},
  pages     = {545-554},
  year      = {2020},
  abstract  = {Preventing malnutrition through consuming nutritionally appropriate resources represents a challenge for foraging animals. This is due to often high variation in the nutritional quality of available resources. Foragers consequently need to evaluate different food sources. However, even the same food source can provide a plethora of nutritional and non-nutritional cues, which could serve for quality assessment. We show that bumblebees, Bombus terrestris , overcome this challenge by relying on lipids as nutritional cue when selecting pollen. The bees 'prioritised' lipid perception in learning experiments and avoided lipid consumption in feeding experiments, which supported survival and reproduction. In contrast, survival and reproduction were severely reduced by increased lipid contents. Our study highlights the importance of fat regulation for pollen foraging bumblebees. It also reveals that nutrient perception, nutrient regulation and reproductive fitness can be linked, which represents an effective strategy enabling quick foraging decisions that prevent malnutrition and maximise fitness.},
  language  = {en}
}
@article{OtienoKarpatiPetersetal.2023,
  author    = {Otieno, Mark and Karpati, Zsolt and Peters, Marcell K. and Duque, Laura and Schmitt, Thomas and Steffan-Dewenter, Ingolf},
  title     = {Elevated ozone and carbon dioxide affects the composition of volatile organic compounds emitted by Vicia faba (L.) and visitation by European orchard bee (Osmia cornuta)},
  series = {PLoS One},
  volume    = {18},
  journal   = {PLoS One},
  number    = {4},
  doi       = {10.1371/journal.pone.0283480},
  url       = {http://nbn-resolving.de/urn:nbn:de:bvb:20-opus-350020},
  year      = {2023},
  abstract  = {Recent studies link increased ozone (O\(_3\)) and carbon dioxide (CO\(_2\)) levels to alteration of plant performance and plant-herbivore interactions, but their interactive effects on plant-pollinator interactions are little understood. Extra floral nectaries (EFNs) are essential organs used by some plants for stimulating defense against herbivory and for the attraction of insect pollinators, e.g., bees. The factors driving the interactions between bees and plants regarding the visitation of bees to EFNs are poorly understood, especially in the face of global change driven by greenhouse gases. Here, we experimentally tested whether elevated levels of O\(_3\) and CO\(_2\) individually and interactively alter the emission of Volatile Organic Compound (VOC) profiles in the field bean plant (Vicia faba, L., Fabaceae), EFN nectar production and EFN visitation by the European orchard bee (Osmia cornuta, Latreille, Megachilidae). Our results showed that O\(_3\) alone had significant negative effects on the blends of VOCs emitted while the treatment with elevated CO\(_2\) alone did not differ from the control. Furthermore, as with O\(_3\) alone, the mixture of O\(_3\) and CO\(_2\) also had a significant difference in the VOCs' profile. O\(_3\) exposure was also linked to reduced nectar volume and had a negative impact on EFN visitation by bees. Increased CO\(_2\) level, on the other hand, had a positive impact on bee visits. Our results add to the knowledge of the interactive effects of O\(_3\) and CO\(_2\) on plant volatiles emitted by Vicia faba and bee responses. As greenhouse gas levels continue to rise globally, it is important to take these findings into consideration to better prepare for changes in plant-insect interactions.},
  language  = {en}
}
@article{DrescherKleinNeumannetal.2017,
  author    = {Drescher, Nora and Klein, Alexandra-Maria and Neumann, Peter and Ya{\~n}ez, Orlando and Leonhardt, Sara D.},
  title     = {Inside Honeybee Hives: Impact of Natural Propolis on the Ectoparasitic Mite Varroa destructor and Viruses},
  series = {Insects},
  volume    = {8},
  journal   = {Insects},
  number    = {1},
  doi       = {10.3390/insects8010015},
  url       = {http://nbn-resolving.de/urn:nbn:de:bvb:20-opus-171164},
  pages     = {15},
  year      = {2017},
  abstract  = {Social immunity is a key factor for honeybee health, including behavioral defense strategies such as the collective use of antimicrobial plant resins (propolis). While laboratory data repeatedly show significant propolis effects, field data are scarce, especially at the colony level. Here, we investigated whether propolis, as naturally deposited in the nests, can protect honeybees against ectoparasitic mites Varroa destructor and associated viruses, which are currently considered the most serious biological threat to European honeybee subspecies, Apis mellifera, globally. Propolis intake of 10 field colonies was manipulated by either reducing or adding freshly collected propolis. Mite infestations, titers of deformed wing virus (DWV) and sacbrood virus (SBV), resin intake, as well as colony strength were recorded monthly from July to September 2013. We additionally examined the effect of raw propolis volatiles on mite survival in laboratory assays. Our results showed no significant effects of adding or removing propolis on mite survival and infestation levels. However, in relation to V. destructor, DWV titers increased significantly less in colonies with added propolis than in propolis-removed colonies, whereas SBV titers were similar. Colonies with added propolis were also significantly stronger than propolis-removed colonies. These findings indicate that propolis may interfere with the dynamics of V. destructor-transmitted viruses, thereby further emphasizing the importance of propolis for honeybee health.},
  language  = {en}
}