@article{ArenasRoces2017,
  author    = {Arenas, Andr{\´e}s and Roces, Flavio},
  title     = {Avoidance of plants unsuitable for the symbiotic fungus in leaf-cutting ants: Learning can take place entirely at the colony dump},
  series = {PLoS ONE},
  volume    = {12},
  journal   = {PLoS ONE},
  number    = {3},
  doi       = {10.1371/journal.pone.0171388},
  url       = {http://nbn-resolving.de/urn:nbn:de:bvb:20-opus-157559},
  pages     = {e0171388},
  year      = {2017},
  abstract  = {Plants initially accepted by foraging leaf-cutting ants are later avoided if they prove unsuitable for their symbiotic fungus. Plant avoidance is mediated by the waste produced in the fungus garden soon after the incorporation of the unsuitable leaves, as foragers can learn plant odors and cues from the damaged fungus that are both present in the recently produced waste particles. We asked whether avoidance learning of plants unsuitable for the symbiotic fungus can take place entirely at the colony dump. In order to investigate whether cues available in the waste chamber induce plant avoidance in na{\"i}ve subcolonies, we exchanged the waste produced by subcolonies fed either fungicide-treated privet leaves or untreated leaves and measured the acceptance of untreated privet leaves before and after the exchange of waste. Second, we evaluated whether foragers could perceive the avoidance cues directly at the dump by quantifying the visits of labeled foragers to the waste chamber. Finally, we asked whether foragers learn to specifically avoid untreated leaves of a plant after a confinement over 3 hours in the dump of subcolonies that were previously fed fungicide-treated leaves of that species. After the exchange of the waste chambers, workers from subcolonies that had access to waste from fungicide-treated privet leaves learned to avoid that plant. One-third of the labeled foragers visited the dump. Furthermore, na{\"i}ve foragers learned to avoid a specific, previously unsuitable plant if exposed solely to cues of the dump during confinement. We suggest that cues at the dump enable foragers to predict the unsuitable effects of plants even if they had never been experienced in the fungus garden.},
  language  = {en}
}
@article{DannerKellerHaerteletal.2017,
  author    = {Danner, Nadja and Keller, Alexander and H{\"a}rtel, Stephan and Steffan-Dewenter, Ingolf},
  title     = {Honey bee foraging ecology: Season but not landscape diversity shapes the amount and diversity of collected pollen},
  series = {PLoS ONE},
  volume    = {12},
  journal   = {PLoS ONE},
  number    = {8},
  doi       = {10.1371/journal.pone.0183716},
  url       = {http://nbn-resolving.de/urn:nbn:de:bvb:20-opus-170424},
  pages     = {e0183716},
  year      = {2017},
  abstract  = {The availability of pollen in agricultural landscapes is essential for the successful growth and reproduction of honey bee colonies (Apis mellifera L.). The quantity and diversity of collected pollen can influence the growth and health of honey bee colonies, but little is known about the influence of landscape structure on pollen diet. In a field experiment, we rotated 16 honey bee colonies across 16 agricultural landscapes, used traps to collect samples of collected pollen and observed intra-colonial dance communication to gain information about foraging distances. DNA metabarcoding was applied to analyze mixed pollen samples. Neither the amount of collected pollen nor pollen diversity was related to landscape diversity. However, we found a strong seasonal variation in the amount and diversity of collected pollen in all sites independent of landscape diversity. The observed increase in foraging distances with decreasing landscape diversity suggests that honey bees compensated for lower landscape diversity by increasing their pollen foraging range in order to maintain pollen amount and diversity. Our results underscore the importance of a diverse pollen diet for honey bee colonies. Agri-environmental schemes aiming to support pollinators should focus on possible spatial and temporal gaps in pollen availability and diversity in agricultural landscapes.},
  language  = {en}
}