title: Evolutionary paths underlying flower color variation in Antirrhinum.
abstract: To understand evolutionary paths connecting diverse biological forms, we defined a three-dimensional genotypic space separating two flower color morphs of Antirrhinum. A hybrid zone between morphs showed a steep cline specifically at genes controlling flower color differences, indicating that these loci are under selection. Antirrhinum species with diverse floral phenotypes formed a U-shaped cloud within the genotypic space. We propose that this cloud defines an evolutionary path that allows flower color to evolve while circumventing less-adaptive regions. Hybridization between morphs located in different arms of the U-shaped path yields low-fitness genotypes, accounting for the observed steep clines at hybrid zones.
authors.affiliation: Department of Cell and Developmental Biology, John Innes Centre, Colney Lane, Norwich NR4 7UH, UK.
authors.forename: Annabel C
authors.initials: AC
authors.lastname: Whibley
authors.forename: Nicolas B
authors.initials: NB
authors.lastname: Langlade
authors.forename: Christophe
authors.initials: C
authors.lastname: Andalo
authors.forename: Andrew I
authors.initials: AI
authors.lastname: Hanna
authors.forename: Andrew
authors.initials: A
authors.lastname: Bangham
authors.forename: Christophe
authors.initials: C
authors.lastname: Thébaud
authors.forename: Enrico
authors.initials: E
authors.lastname: Coen
mesh_terms: D000220:Adaptation, Biological; D000483:Alleles; D032161:Antirrhinum / Q000145:classification / Q000235:genetics*; D001483:Base Sequence; D005075:Biological Evolution; D003433:Crosses, Genetic; D035264:Flowers / Q000235:genetics*; D051456:Gene Flow; D005787:Gene Frequency; D017343:Genes, Plant; D049810:Genetic Speciation; D005838:Genotype; D006239:Haplotypes; D006824:Hybridization, Genetic; D008957:Models, Genetic; D008969:Molecular Sequence Data; D010641:Phenotype; D010802:Phylogeny; D010858:Pigmentation / Q000235:genetics*; D010860:Pigments, Biological / Q000235:genetics; D025341:Principal Component Analysis; D012641:Selection, Genetic
chemical_list: D010860:Pigments, Biological