title: Divergent selection on opsins drives incipient speciation in Lake Victoria cichlids.
abstract: Divergent natural selection acting on ecological traits, which also affect mate choice, is a key element of ecological speciation theory, but has not previously been demonstrated at the molecular gene level to our knowledge. Here we demonstrate parallel evolution in two cichlid genera under strong divergent selection in a gene that affects both. Strong divergent natural selection fixed opsin proteins with different predicted light absorbance properties at opposite ends of an environmental gradient. By expressing them and measuring absorbance, we show that the reciprocal fixation adapts populations to divergent light environments. The divergent evolution of the visual system coincides with divergence in male breeding coloration, consistent with incipient ecological by-product speciation.
authors.affiliation: Graduate School of Bioscience and Biotechnology, Tokyo Institute of Technology, Yokohama, Japan.
authors.forename: Yohey
authors.initials: Y
authors.lastname: Terai
authors.forename: Ole
authors.initials: O
authors.lastname: Seehausen
authors.forename: Takeshi
authors.initials: T
authors.lastname: Sasaki
authors.forename: Kazuhiko
authors.initials: K
authors.lastname: Takahashi
authors.forename: Shinji
authors.initials: S
authors.lastname: Mizoiri
authors.forename: Tohru
authors.initials: T
authors.lastname: Sugawara
authors.forename: Tetsu
authors.initials: T
authors.lastname: Sato
authors.forename: Masakatsu
authors.initials: M
authors.lastname: Watanabe
authors.forename: Nellie
authors.initials: N
authors.lastname: Konijnendijk
authors.forename: Hillary D J
authors.initials: HD
authors.lastname: Mrosso
authors.forename: Hidenori
authors.initials: H
authors.lastname: Tachida
authors.forename: Hiroo
authors.initials: H
authors.lastname: Imai
authors.forename: Yoshinori
authors.initials: Y
authors.lastname: Shichida
authors.forename: Norihiro
authors.initials: N
authors.lastname: Okada
mesh_terms: D000351:Africa, Eastern; D000483:Alleles; D000818:Animals; D001522:Behavior, Animal; D023681:Cichlids / Q000145:classification* / Q000235:genetics*; D005618:Fresh Water; D049810:Genetic Speciation; D008297:Male; D008969:Molecular Sequence Data; D010860:Pigments, Biological / Q000737:chemistry / Q000378:metabolism; D017299:Rod Opsins / Q000235:genetics*; D012641:Selection, Genetic; D013057:Spectrum Analysis
chemical_list: D010860:Pigments, Biological; D017299:Rod Opsins