title: Incipient speciation in Drosophila melanogaster involves chemical signals.
abstract: The sensory and genetic bases of incipient speciation between strains of Drosophila melanogaster from Zimbabwe and those from elsewhere are unknown. We studied mating behaviour between eight strains - six from Zimbabwe, together with two cosmopolitan strains. The Zimbabwe strains showed significant sexual isolation when paired with cosmopolitan males, due to Zimbabwe females discriminating against these males. Our results show that flies' cuticular hydrocarbons (CHs) were involved in this sexual isolation, but that visual and acoustic signals were not. The mating frequency of Zimbabwe females was highly significantly negatively correlated with the male's relative amount of 7-tricosene (%7-T), while the mating of cosmopolitan females was positively correlated with %7-T. Variation in transcription levels of two hydrocarbon-determining genes, desat1 and desat2, did not correlate with the observed mating patterns. Our study represents a step forward in our understanding of the sensory processes involved in this classic case of incipient speciation.
authors.affiliation: Centre des Sciences du Goût et de l'Alimentation, UMR6265 CNRS, UMR1324 INRA, Université de Bourgogne, Agrosup Dijon, 6, Bd Gabriel, 21000 Dijon, France.
authors.forename: Micheline
authors.initials: M
authors.lastname: Grillet
authors.forename: Claude
authors.initials: C
authors.lastname: Everaerts
authors.forename: Benjamin
authors.initials: B
authors.lastname: Houot
authors.forename: Michael G
authors.initials: MG
authors.lastname: Ritchie
authors.forename: Matthew
authors.initials: M
authors.lastname: Cobb
authors.forename: Jean-François
authors.initials: JF
authors.lastname: Ferveur
mesh_terms: D000818:Animals; D004331:Drosophila melanogaster / Q000145:classification* / Q000378:metabolism; D005260:Female; D006838:Hydrocarbons / Q000378:metabolism; D008297:Male
chemical_list: D006838:Hydrocarbons