title: Two male-killing Wolbachia strains coexist within a population of the butterfly Acraea encedon.
abstract: Inherited bacteria that kill male hosts early in their development are known from five insect orders. We ask to what extent the incidence of male-killers might be restricted by the rate at which new host-parasite interactions arise, by testing whether multiple male-killers have invaded a single host species. In Uganda, the butterflies Acraea encedon and A. encedana are both infected by the same strain of male-killing Wolbachia and there was no evidence of variation within the population. In Tanzanian A. encedon however, two phylogenetically distinct strains of male-killing Wolbachia were found within the same population. If this pattern of male-killer polymorphism is found to be general across infected species, it suggests that new male-killing infections arise frequently on an evolutionary time scale. Whether this polymorphism is stable, and what forces may be maintaining it, are unknown.
authors.affiliation: Department of Genetics, Cambridge University, Downing Street, Cambridge, CB2 3EH, UK. fmj1001@mole.bio.cam.ac.uk
authors.forename: F M
authors.initials: FM
authors.lastname: Jiggins
authors.forename: G D
authors.initials: GD
authors.lastname: Hurst
authors.forename: J H
authors.initials: JH
authors.lastname: Schulenburg
authors.forename: M E
authors.initials: ME
authors.lastname: Majerus
mesh_terms: D000818:Animals; D000900:Anti-Bacterial Agents / Q000494:pharmacology; D002080:Butterflies / Q000187:drug effects / Q000382:microbiology*; D005260:Female; D006790:Host-Parasite Interactions / Q000187:drug effects / Q000235:genetics; D008297:Male; D010802:Phylogeny; D012737:Sex Factors; D012744:Sex Ratio; D013752:Tetracycline / Q000494:pharmacology; D020577:Wolbachia / Q000235:genetics* / Q000502:physiology
chemical_list: D000900:Anti-Bacterial Agents; D013752:Tetracycline