title: A pharyngeal jaw evolutionary innovation facilitated extinction in Lake Victoria cichlids.
abstract: Evolutionary innovations, traits that give species access to previously unoccupied niches, may promote speciation and adaptive radiation. Here, we show that such innovations can also result in competitive inferiority and extinction. We present evidence that the modified pharyngeal jaws of cichlid fishes and several marine fish lineages, a classic example of evolutionary innovation, are not universally beneficial. A large-scale analysis of dietary evolution across marine fish lineages reveals that the innovation compromises access to energy-rich predator niches. We show that this competitive inferiority shaped the adaptive radiation of cichlids in Lake Tanganyika and played a pivotal and previously unrecognized role in the mass extinction of cichlid fishes in Lake Victoria after Nile perch invasion.
authors.affiliation: Department of Evolution and Ecology and Center for Population Biology, University of California, Davis, CA 95616, USA. Institute of Ecology and Evolution, University of Bern, CH-3012 Bern, Switzerland. Department of Fish Ecology and Evolution, Eawag, Swiss Federal Institute for Aquatic Science and Technology, CH-6047 Kastanienbaum, Switzerland. mcgee.matthew@gmail.com.
authors.forename: Matthew D
authors.initials: MD
authors.lastname: McGee
authors.affiliation: Department of Ecology and Evolutionary Biology, University of Tennessee, Knoxville, TN 37996, USA.
authors.forename: Samuel R
authors.initials: SR
authors.lastname: Borstein
authors.affiliation: Department of Evolution and Ecology and Center for Population Biology, University of California, Davis, CA 95616, USA.
authors.forename: Russell Y
authors.initials: RY
authors.lastname: Neches
authors.affiliation: Zoological Institute, University of Basel, CH-4051 Basel, Switzerland.
authors.forename: Heinz H
authors.initials: HH
authors.lastname: Buescher
authors.affiliation: Institute of Ecology and Evolution, University of Bern, CH-3012 Bern, Switzerland. Department of Fish Ecology and Evolution, Eawag, Swiss Federal Institute for Aquatic Science and Technology, CH-6047 Kastanienbaum, Switzerland.
authors.forename: Ole
authors.initials: O
authors.lastname: Seehausen
authors.affiliation: Department of Evolution and Ecology and Center for Population Biology, University of California, Davis, CA 95616, USA.
authors.forename: Peter C
authors.initials: PC
authors.lastname: Wainwright
mesh_terms: D000220:Adaptation, Biological; D000818:Animals; D005075:Biological Evolution; D023681:Cichlids / Q000033:anatomy & histology*; D004435:Eating; D053476:Extinction, Biological; D007568:Jaw / Q000033:anatomy & histology*; D060106:Lakes; D008295:Malawi; D010614:Pharynx / Q000033:anatomy & histology*; D013636:Tanzania