@article{SchilcherThammStrubeBlossetal.2021,
  author    = {Schilcher, Felix and Thamm, Markus and Strube-Bloss, Martin and Scheiner, Ricarda},
  title     = {Opposing actions of octopamine and tyramine on honeybee vision},
  series = {Biomolecules},
  volume    = {11},
  journal   = {Biomolecules},
  number    = {9},
  issn      = {2218-273X},
  doi       = {10.3390/biom11091374},
  url       = {http://nbn-resolving.de/urn:nbn:de:bvb:20-opus-246214},
  year      = {2021},
  abstract  = {The biogenic amines octopamine and tyramine are important neurotransmitters in insects and other protostomes. They play a pivotal role in the sensory responses, learning and memory and social organisation of honeybees. Generally, octopamine and tyramine are believed to fulfil similar roles as their deuterostome counterparts epinephrine and norepinephrine. In some cases opposing functions of both amines have been observed. In this study, we examined the functions of tyramine and octopamine in honeybee responses to light. As a first step, electroretinography was used to analyse the effect of both amines on sensory sensitivity at the photoreceptor level. Here, the maximum receptor response was increased by octopamine and decreased by tyramine. As a second step, phototaxis experiments were performed to quantify the behavioural responses to light following treatment with either amine. Octopamine increased the walking speed towards different light sources while tyramine decreased it. This was independent of locomotor activity. Our results indicate that tyramine and octopamine act as functional opposites in processing responses to light.},
  language  = {en}
}
@article{SchilcherHilsmannRauscheretal.2021,
  author    = {Schilcher, Felix and Hilsmann, Lioba and Rauscher, Lisa and Değirmenci, Laura and Krischke, Markus and Krischke, Beate and Ankenbrand, Markus and Rutschmann, Benjamin and Mueller, Martin J. and Steffan-Dewenter, Ingolf and Scheiner, Ricarda},
  title     = {In vitro rearing changes social task performance and physiology in honeybees},
  series = {Insects},
  volume    = {13},
  journal   = {Insects},
  number    = {1},
  issn      = {2075-4450},
  doi       = {10.3390/insects13010004},
  url       = {http://nbn-resolving.de/urn:nbn:de:bvb:20-opus-252305},
  year      = {2021},
  abstract  = {In vitro rearing of honeybee larvae is an established method that enables exact control and monitoring of developmental factors and allows controlled application of pesticides or pathogens. However, only a few studies have investigated how the rearing method itself affects the behavior of the resulting adult honeybees. We raised honeybees in vitro according to a standardized protocol: marking the emerging honeybees individually and inserting them into established colonies. Subsequently, we investigated the behavioral performance of nurse bees and foragers and quantified the physiological factors underlying the social organization. Adult honeybees raised in vitro differed from naturally reared honeybees in their probability of performing social tasks. Further, in vitro-reared bees foraged for a shorter duration in their life and performed fewer foraging trips. Nursing behavior appeared to be unaffected by rearing condition. Weight was also unaffected by rearing condition. Interestingly, juvenile hormone titers, which normally increase strongly around the time when a honeybee becomes a forager, were significantly lower in three- and four-week-old in vitro bees. The effects of the rearing environment on individual sucrose responsiveness and lipid levels were rather minor. These data suggest that larval rearing conditions can affect the task performance and physiology of adult bees despite equal weight, pointing to an important role of the colony environment for these factors. Our observations of behavior and metabolic pathways offer important novel insight into how the rearing environment affects adult honeybees.},
  language  = {en}
}
@article{ScheinerLimMeixneretal.2021,
  author    = {Scheiner, Ricarda and Lim, Kayun and Meixner, Marina D. and Gabel, Martin S.},
  title     = {Comparing the appetitive learning performance of six European honeybee subspecies in a common apiary},
  series = {Insects},
  volume    = {12},
  journal   = {Insects},
  number    = {9},
  issn      = {2075-4450},
  doi       = {10.3390/insects12090768},
  url       = {http://nbn-resolving.de/urn:nbn:de:bvb:20-opus-245180},
  year      = {2021},
  abstract  = {The Western honeybee (Apis mellifera L.) is one of the most widespread insects with numerous subspecies in its native range. How far adaptation to local habitats has affected the cognitive skills of the different subspecies is an intriguing question that we investigate in this study. Naturally mated queens of the following five subspecies from different parts of Europe were transferred to Southern Germany: A. m. iberiensis from Portugal, A. m. mellifera from Belgium, A. m. macedonica from Greece, A. m. ligustica from Italy, and A. m. ruttneri from Malta. We also included the local subspecies A. m. carnica in our study. New colonies were built up in a common apiary where the respective queens were introduced. Worker offspring from the different subspecies were compared in classical olfactory learning performance using the proboscis extension response. Prior to conditioning, we measured individual sucrose responsiveness to investigate whether possible differences in learning performances were due to differential responsiveness to the sugar water reward. Most subspecies did not differ in their appetitive learning performance. However, foragers of the Iberian honeybee, A. m. iberiensis, performed significantly more poorly, despite having a similar sucrose responsiveness. We discuss possible causes for the poor performance of the Iberian honeybees, which may have been shaped by adaptation to the local habitat.},
  language  = {en}
}