title: Divergent host-plant use promotes reproductive isolation among cynipid gall wasp populations.
abstract: Ecological speciation occurs when reproductive isolation evolves as a consequence of divergent natural selection among environments. A direct prediction of this process is that ecologically divergent pairs of populations will exhibit greater reproductive isolation than ecologically similar pairs of populations. By comparing allopatric populations of the cynipid gall wasp Belonocnema treatae infesting Quercus virginiana and Quercus geminata, we tested the role that divergent host use plays in generating ecological divergence and sexual isolation. We found differences in body size and gall structure associated with divergent host use, but no difference in neutral genetic divergence between populations on the same or different host plant. We observed significant assortative mating between populations from alternative host plants but not between allopatric populations on the same host plant. Thus, we provide evidence that divergent host use promotes speciation among gall wasp populations.
authors.affiliation: Department of Biological Sciences, Advanced Diagnostics and Therapeutics, University of Notre Dame, Notre Dame, IN 46556, USA. scott.p.egan@nd.edu
authors.forename: Scott P
authors.initials: SP
authors.lastname: Egan
authors.forename: Glen R
authors.initials: GR
authors.lastname: Hood
authors.forename: Jeff L
authors.initials: JL
authors.lastname: Feder
authors.forename: James R
authors.initials: JR
authors.lastname: Ott
mesh_terms: D000220:Adaptation, Biological; D000818:Animals; D049628:Body Size; D003307:Copulation; D004272:DNA, Mitochondrial / Q000032:analysis / Q000235:genetics; D017753:Ecosystem; D003576:Electron Transport Complex IV / Q000235:genetics; D005260:Female; D049810:Genetic Speciation; D005828:Genetics, Population / Q000379:methods; D006790:Host-Parasite Interactions; D008297:Male; D008928:Mitochondria / Q000235:genetics; D010941:Plant Tumors / Q000469:parasitology; D029963:Quercus / Q000469:parasitology*; D012098:Reproduction; D060047:Reproductive Isolation; D014863:Wasps / Q000033:anatomy & histology / Q000235:genetics / Q000472:pathogenicity*
chemical_list: D004272:DNA, Mitochondrial; D003576:Electron Transport Complex IV