title: Fecal-Derived Phenol Induces Egg-Laying Aversion in Drosophila.
abstract: Feces is an abundant, rich source of energy, utilized by a myriad of organisms, not least by members of the order Diptera, i.e., flies. How Drosophila melanogaster reacts to fecal matter remains unclear. Here, we examined oviposition behavior toward a range of fecal samples from mammals native to the putative Southeast African homeland of the fly. We show that D. melanogaster display a strong oviposition aversion toward feces from carnivorous mammals but indifference or even attraction toward herbivore dung. We identify a set of four predictor volatiles, which can be used to differentiate fecal from non-fecal matter, as well as separate carnivore from herbivore feces. Of these volatiles, phenol-indicative of carnivore feces-confers egg-laying aversion and is detected by a single class of sensory neurons expressing Or46a. The Or46a-expressing neurons are necessary and sufficient for oviposition site aversion. We further demonstrate that carnivore feces-unlike herbivore dung-contain a high rate of pathogenic bacteria taxa. These harmful bacteria produce phenol from L-tyrosine, an amino acid specifically enriched in high protein diets, such as consumed by carnivores. Finally, we demonstrate that carnivore feces, as well as phenol, is also avoided by a ball-rolling species of dung beetle, suggesting that phenol is a widespread avoidance signal because of its association with pathogenic bacteria.
authors.affiliation: Department of Biology, Lund University, 223 62 Lund, Sweden.
authors.forename: Suzan
authors.initials: S
authors.lastname: Mansourian
authors.affiliation: Department of Biology, Lund University, 223 62 Lund, Sweden.
authors.forename: Jacob
authors.initials: J
authors.lastname: Corcoran
authors.affiliation: Department of Biology, Lund University, 223 62 Lund, Sweden.
authors.forename: Anders
authors.initials: A
authors.lastname: Enjin
authors.affiliation: Department of Biology, Lund University, 223 62 Lund, Sweden.
authors.forename: Christer
authors.initials: C
authors.lastname: Löfstedt
authors.affiliation: Department of Biology, Lund University, 223 62 Lund, Sweden.
authors.forename: Marie
authors.initials: M
authors.lastname: Dacke
authors.affiliation: Department of Biology, Lund University, 223 62 Lund, Sweden. Electronic address: marcus.stensmyr@biol.lu.se.
authors.forename: Marcus C
authors.initials: MC
authors.lastname: Stensmyr
mesh_terms: D000818:Animals; D001362:Avoidance Learning; D004032:Diet; D004331:Drosophila melanogaster / Q000502:physiology*; D005243:Feces / Q000737:chemistry*; D005260:Female; D008322:Mammals / Q000502:physiology; D010058:Oviposition; D010636:Phenols / Q000378:metabolism*; D011984:Sensory Receptor Cells / Q000378:metabolism
chemical_list: D010636:Phenols