@article{DegenHovestadtMitesseretal.2017,
  author    = {Degen, Tobias and Hovestadt, Thomas and Mitesser, Oliver and H{\"o}lker, Franz},
  title     = {Altered sex-specific mortality and female mating success: ecological effects and evolutionary responses},
  series = {Ecosphere},
  volume    = {8},
  journal   = {Ecosphere},
  number    = {5},
  doi       = {10.1002/ecs2.1820},
  url       = {http://nbn-resolving.de/urn:nbn:de:bvb:20-opus-170953},
  pages     = {e01820},
  year      = {2017},
  abstract  = {Theory predicts that males and females should often join the mating pool at different times (sexual dimorphism in timing of emergence [SDT]) as the degree of SDT affects female mating success. We utilize an analytical model to explore (1) how important SDT is for female mating success, (2) how mating success might change if either sex's mortality (abruptly) increases, and (3) to what degree evolutionary responses in SDT may be able to mitigate the consequences of such mortality increase. Increasing male pre-mating mortality has a non-linear effect on the fraction of females mated: The effect is initially weak, but at some critical level a further increase in male mortality has a stronger effect than a similar increase in female mortality. Such a change is expected to impose selection for reduced SDT. Increasing mortality during the mating season has always a stronger effect on female mating success if the mortality affects the sex that emerges first. This bias results from the fact that enhancing mortality of the earlier emerging sex reduces female-male encounter rates. However, an evolutionary response in SDT may effectively mitigate such consequences. Further, if considered independently for females and males, the predicted evolutionary response in SDT could be quite dissimilar. The difference between female and male evolutionary response in SDT leads to marked differences in the fraction of fertilized females under certain conditions. Our model may provide general guidelines for improving harvesting of populations, conservation management of rare species under altered environmental conditions, or maintaining long-term efficiency of pest-control measures.},
  language  = {en}
}
@article{DegenHovestadtMitesseretal.2015,
  author    = {Degen, Tobias and Hovestadt, Thomas and Mitesser, Oliver and H{\"o}lker, Franz},
  title     = {High female survival promotes evolution of protogyny and xexual conflict},
  series = {PLoS ONE},
  volume    = {10},
  journal   = {PLoS ONE},
  number    = {3},
  doi       = {10.1371/journal.pone.0118354},
  url       = {http://nbn-resolving.de/urn:nbn:de:bvb:20-opus-143586},
  pages     = {e0118354},
  year      = {2015},
  abstract  = {Existing models explaining the evolution of sexual dimorphism in the timing of emergence (SDT) in Lepidoptera assume equal mortality rates for males and females. The limiting assumption of equal mortality rates has the consequence that these models are only able to explain the evolution of emergence of males before females, i.e. protandry-the more common temporal sequence of emergence in Lepidoptera. The models fail, however, in providing adaptive explanations for the evolution of protogyny, where females emerge before males, but protogyny is not rare in insects. The assumption of equal mortality rates seems too restrictive for many insects, such as butterflies. To investigate the influence of unequal mortality rates on the evolution of SDT, we present a generalised version of a previously published model where we relax this assumption. We find that longer life-expectancy of females compared to males can indeed favour the evolution of protogyny as a fitness enhancing strategy. Moreover, the encounter rate between females and males and the sex-ratio are two important factors that also influence the evolution of optimal SDT. If considered independently for females and males the predicted strategies can be shown to be evolutionarily stable (ESS). Under the assumption of equal mortality rates the difference between the females' and males' ESS remains typically very small. However, female and male ESS may be quite dissimilar if mortality rates are different. This creates the potential for an 'evolutionary conflict' between females and males. Bagworm moths (Lepidoptera: Psychidae) provide an exemplary case where life-history attributes are such that protogyny should indeed be the optimal emergence strategy from the males' and females' perspectives: (i) Female longevity is considerably larger than that of males, (ii) encounter rates between females and males are presumably low, and (iii) females mate only once. Protogyny is indeed the general mating strategy found in the bagworm family.},
  language  = {en}
}