@article{HovestadtPoethkeMessner2000,
  author    = {Hovestadt, Thomas and Poethke, Hans J. and Messner, Stefan},
  title     = {Variability in dispersal distances generates typical successional patterns: a simple simulation model},
  url       = {http://nbn-resolving.de/urn:nbn:de:bvb:20-opus-48178},
  year      = {2000},
  abstract  = {More recently, it became clear that conclusions drawn from traditional ecological theory may be altered substantially if the spatial dimension of species interactions is considered explicitly. Regardless of the details of these models, spatially explicit simulations of ecological processes have nearly universally shown that spatial or spatio-temporal patterns in species distributions can emerge even from homogeneous starting conditions; limited dispersal is one of the key factors responsible for the development of such aggregated and patchy distributions (cf., Pacala 1986, Holmes et al. 1994, Molofsky 1994, Tilman 1994, Bascompte and Sole 1995, 1997, 1998, Jeltsch et al. 1999). In line with these ideas, we wish to draw attention to the fact that in heterogeneous landscapes differences in characteristic dispersal distances between species are a sufficient precondition for the emergence of a successional pattern. We will use a simple, spatially explicit simulation program to demonstrate the validity of this statement. We will also show that the speed of the successional progress depends on scale and heterogeneity in the distribution of suitable habitat.},
  language  = {en}
}
@article{HornMitesserHovestadtetal.2019,
  author    = {Horn, Melanie and Mitesser, Oliver and Hovestadt, Thomas and Yoshii, Taishi and Rieger, Dirk and Helfrich-F{\"o}rster, Charlotte},
  title     = {The circadian clock improves fitness in the fruit fly, Drosophila melanogaster},
  series = {Frontiers in Physiology},
  volume    = {10},
  journal   = {Frontiers in Physiology},
  number    = {1374},
  issn      = {1664-042X},
  doi       = {10.3389/fphys.2019.01374},
  url       = {http://nbn-resolving.de/urn:nbn:de:bvb:20-opus-195738},
  year      = {2019},
  abstract  = {It is assumed that a properly timed circadian clock enhances fitness, but only few studies have truly demonstrated this in animals. We raised each of the three classical Drosophila period mutants for >50 generations in the laboratory in competition with wildtype flies. The populations were either kept under a conventional 24-h day or under cycles that matched the mutant's natural cycle, i.e., a 19-h day in the case of pers mutants and a 29-h day for perl mutants. The arrhythmic per0 mutants were grown together with wildtype flies under constant light that renders wildtype flies similar arrhythmic as the mutants. In addition, the mutants had to compete with wildtype flies for two summers in two consecutive years under outdoor conditions. We found that wildtype flies quickly outcompeted the mutant flies under the 24-h laboratory day and under outdoor conditions, but perl mutants persisted and even outnumbered the wildtype flies under the 29-h day in the laboratory. In contrast, pers and per0 mutants did not win against wildtype flies under the 19-h day and constant light, respectively. Our results demonstrate that wildtype flies have a clear fitness advantage in terms of fertility and offspring survival over the period mutants and - as revealed for perl mutants - this advantage appears maximal when the endogenous period resonates with the period of the environment. However, the experiments indicate that perl and pers persist at low frequencies in the population even under the 24-h day. This may be a consequence of a certain mating preference of wildtype and heterozygous females for mutant males and time differences in activity patterns between wildtype and mutants.},
  language  = {en}
}
@article{SponslerKallnikRequieretal.2022,
  author    = {Sponsler, Douglas and Kallnik, Katharina and Requier, Fabrice and Classen, Alice and Maihoff, A. Fabienne and Sieger, Johanna and Steffan-Dewenter, Ingolf},
  title     = {Floral preferences of mountain bumble bees are constrained by functional traits but flexible through elevation and season},
  series = {Oikos},
  volume    = {2022},
  journal   = {Oikos},
  number    = {3},
  doi       = {10.1111/oik.08902},
  url       = {http://nbn-resolving.de/urn:nbn:de:bvb:20-opus-259653},
  year      = {2022},
  abstract  = {Patterns of resource use by animals can clarify how ecological communities have assembled in the past, how they currently function and how they are likely to respond to future perturbations. Bumble bees (Hymentoptera: Bombus spp.) and their floral hosts provide a diverse yet tractable system in which to explore resource selection in the context of plant-pollinator networks. Under conditions of resource limitation, the ability of bumble bees species to coexist should depend on dietary niche overlap. In this study, we report patterns and dynamics of floral morphotype preferences in a mountain bumble bee community based on ~13 000 observations of bumble bee floral visits recorded along a 1400 m elevation gradient. We found that bumble bees are highly selective generalists, rarely visiting floral morphotypes at the rates predicted by their relative abundances. Preferences also differed markedly across bumble bee species, and these differences were well-explained by variation in bumble bee tongue length, generating patterns of preference similarity that should be expected to predict competition under conditions of resource limitation. Within species, though, morphotype preferences varied by elevation and season, possibly representing adaptive flexibility in response to the high elevational and seasonal turnover of mountain floral communities. Patterns of resource partitioning among bumble bee communities may determine which species can coexist under the altered distributions of bumble bees and their floral hosts caused by climate and land use change.},
  language  = {en}
}