@article{MeucheBrusaLinsenmairetal.2013,
  author    = {Meuche, Ivonne and Brusa, Oscar and Linsenmair, K. Eduard and Keller, Alexander and Pr{\"o}hl, Heike},
  title     = {Only distance matters - non-choosy females in a poison frog population},
  series = {Frontiers in Zoology},
  volume    = {10},
  journal   = {Frontiers in Zoology},
  number    = {29},
  issn      = {1742-9994},
  doi       = {10.1186/1742-9994-10-29},
  url       = {http://nbn-resolving.de/urn:nbn:de:bvb:20-opus-122617},
  year      = {2013},
  abstract  = {Background: Females have often been shown to exhibit preferences for certain male traits. However, little is known about behavioural rules females use when searching for mates in their natural habitat. We investigated mate sampling tactics and related costs in the territorial strawberry poison frog (Oophaga pumilio) possessing a lek-like mating system, where both sequential and simultaneous sampling might occur. We continuously monitored the sampling pattern and behaviour of females during the complete period between two successive matings. Results: We found no evidence that females compared males by visiting them. Instead females mated with the closest calling male irrespective of his acoustic and physical traits, and territory size. Playback experiments in the natural home ranges of receptive females revealed that tested females preferred the nearest speaker and did not discriminate between low and high call rates or dominant frequencies. Conclusions: Our results suggest that females of O. pumilio prefer the closest calling male in the studied population. We hypothesize that the sampling tactic in this population is affected by 1) a strongly female biased sex ratio and 2) a low variance in traits of available males due to strong male-male competition, preventing low quality males from defending a territory and mating.},
  language  = {en}
}
@article{RoedelBredeHirschfeldetal.2013,
  author    = {R{\"o}del, Mark-Oliver and Brede, Christian and Hirschfeld, Mareike and Schmitt, Thomas and Favreau, Philippe and St{\"o}cklin, Reto and Wunder, Cora and Mebs, Dietrich},
  title     = {Chemical Camouflage - A Frog's Strategy to Co-Exist with Aggressive Ants},
  series = {PLOS ONE},
  volume    = {8},
  journal   = {PLOS ONE},
  number    = {12},
  issn      = {1932-6203},
  doi       = {10.1371/journal.pone.0081950},
  url       = {http://nbn-resolving.de/urn:nbn:de:bvb:20-opus-128181},
  pages     = {e81950},
  year      = {2013},
  abstract  = {Whereas interspecific associations receive considerable attention in evolutionary, behavioural and ecological literature, the proximate bases for these associations are usually unknown. This in particular applies to associations between vertebrates with invertebrates. The West-African savanna frog Phrynomantis microps lives in the underground nest of ponerine ants (Paltothyreus tarsatus). The ants usually react highly aggressively when disturbed by fiercely stinging, but the frog is not attacked and lives unharmed among the ants. Herein we examined the proximate mechanisms for this unusual association. Experiments with termites and mealworms covered with the skin secretion of the frog revealed that specific chemical compounds seem to prevent the ants from stinging. By HPLC-fractionation of an aqueous solution of the frogs' skin secretion, two peptides of 1,029 and 1,143 Da were isolated and found to inhibit the aggressive behaviour of the ants. By de novo sequencing using tandem mass spectrometry, the amino acid sequence of both peptides consisting of a chain of 9 and 11 residues, respectively, was elucidated. Both peptides were synthesized and tested, and exhibited the same inhibitory properties as the original frog secretions. These novel peptides most likely act as an appeasement allomone and may serve as models for taming insect aggression.},
  language  = {en}
}