title: Genetics of ecological divergence during speciation.
abstract: Ecological differences often evolve early in speciation as divergent natural selection drives adaptation to distinct ecological niches, leading ultimately to reproductive isolation. Although this process is a major generator of biodiversity, its genetic basis is still poorly understood. Here we investigate the genetic architecture of niche differentiation in a sympatric species pair of threespine stickleback fish by mapping the environment-dependent effects of phenotypic traits on hybrid feeding and performance under semi-natural conditions. We show that multiple, unlinked loci act largely additively to determine position along the major niche axis separating these recently diverged species. We also find that functional mismatch between phenotypic traits reduces the growth of some stickleback hybrids beyond that expected from an intermediate phenotype, suggesting a role for epistasis between the underlying genes. This functional mismatch might lead to hybrid incompatibilities that are analogous to those underlying intrinsic reproductive isolation but depend on the ecological context.
authors.affiliation: 1] Fred Hutchinson Cancer Research Center, Human Biology and Basic Sciences Divisions, 1100 Fairview Avenue North, Seattle, Washington 98109, USA [2] University of British Columbia, Biodiversity Research Centre and Zoology Department, 6270 University Boulevard, Vancouver, British Columbia V6T 1Z4, Canada.
authors.forename: Matthew E
authors.initials: ME
authors.lastname: Arnegard
authors.affiliation: University of California at Davis, Department of Evolution and Ecology, One Shields Avenue, Davis, California 95616, USA.
authors.forename: Matthew D
authors.initials: MD
authors.lastname: McGee
authors.affiliation: EAWAG, Department of Aquatic Ecology, Center for Ecology, Evolution, and Biogeochemistry, Seestrasse 79, 6047 Kastanienbaum, Switzerland.
authors.forename: Blake
authors.initials: B
authors.lastname: Matthews
authors.affiliation: University of British Columbia, Biodiversity Research Centre and Zoology Department, 6270 University Boulevard, Vancouver, British Columbia V6T 1Z4, Canada.
authors.forename: Kerry B
authors.initials: KB
authors.lastname: Marchinko
authors.affiliation: University of British Columbia, Biodiversity Research Centre and Zoology Department, 6270 University Boulevard, Vancouver, British Columbia V6T 1Z4, Canada.
authors.forename: Gina L
authors.initials: GL
authors.lastname: Conte
authors.affiliation: University of British Columbia, Biodiversity Research Centre and Zoology Department, 6270 University Boulevard, Vancouver, British Columbia V6T 1Z4, Canada.
authors.forename: Sahriar
authors.initials: S
authors.lastname: Kabir
authors.affiliation: University of British Columbia, Biodiversity Research Centre and Zoology Department, 6270 University Boulevard, Vancouver, British Columbia V6T 1Z4, Canada.
authors.forename: Nicole
authors.initials: N
authors.lastname: Bedford
authors.affiliation: 1] Uppsala University, Department of Animal Ecology, Evolutionary Biology Centre (EBC), Norbyvägen 18D, SE-75236 Uppsala, Sweden [2] Swedish University of Agricultural Sciences, Department of Aquatic Resources, Stångholmsvägen 2, SE-17893 Drottningholm, Sweden.
authors.forename: Sara
authors.initials: S
authors.lastname: Bergek
authors.affiliation: Stanford University School of Medicine, Department of Developmental Biology and Howard Hughes Medical Institute, 279 Campus Drive, Stanford, California 94305, USA.
authors.forename: Yingguang Frank
authors.initials: YF
authors.lastname: Chan
authors.affiliation: Stanford University School of Medicine, Department of Developmental Biology and Howard Hughes Medical Institute, 279 Campus Drive, Stanford, California 94305, USA.
authors.forename: Felicity C
authors.initials: FC
authors.lastname: Jones
authors.affiliation: Stanford University School of Medicine, Department of Developmental Biology and Howard Hughes Medical Institute, 279 Campus Drive, Stanford, California 94305, USA.
authors.forename: David M
authors.initials: DM
authors.lastname: Kingsley
authors.affiliation: Fred Hutchinson Cancer Research Center, Human Biology and Basic Sciences Divisions, 1100 Fairview Avenue North, Seattle, Washington 98109, USA.
authors.forename: Catherine L
authors.initials: CL
authors.lastname: Peichel
authors.affiliation: University of British Columbia, Biodiversity Research Centre and Zoology Department, 6270 University Boulevard, Vancouver, British Columbia V6T 1Z4, Canada.
authors.forename: Dolph
authors.initials: D
authors.lastname: Schluter
mesh_terms: D000222:Adaptation, Physiological; D000818:Animals; D044822:Biodiversity; D049628:Body Size; D004463:Ecology; D005247:Feeding Behavior; D049810:Genetic Speciation; D010641:Phenotype; D012641:Selection, Genetic; D023701:Smegmamorpha / Q000033:anatomy & histology / Q000235:genetics* / Q000254:growth & development / Q000502:physiology*