title: Next generation phylogeography of cave and surface Astyanax mexicanus.
abstract: The loss of traits is a commonly observed evolutionary pattern in cave organisms, but due to extensive morphological convergence, inferring relationships between cave and surface populations can be difficult. For instance, Astyanax mexicanus (the blind Mexican cavefish) is thought to have repeatedly lost its eyes following colonization of cave environments, but the number of evolutionarily independent invasions of this species into caves remains unclear. Because of these repeated losses, it has become a model organism for studying the genetic basis of phenotypic trait loss. Here we reconstruct a high-resolution phylogeography for A. mexicanus inferred from both mitochondrial DNA and several thousand single nucleotide polymorphisms. We provide novel insight into the origin of cave populations from the Sabinos and Río Subterráneo caves and present evidence that the Sabinos cave population is part of a unique cave lineage unrelated to other A. mexicanus cave populations. Our results indicate A. mexicanus cave populations have at least four independent origins.
authors.affiliation: Department of Biological Sciences, University of New Orleans, 2000 Lakeshore Drive, New Orleans, LA 70148, USA.
authors.forename: Lyndon M
authors.initials: LM
authors.lastname: Coghill
authors.affiliation: Department of Ecology and Evolutionary Biology, University of Tennessee, Knoxville, 569 Dabney Hall, Knoxville, TN 37996, USA.
authors.forename: C
authors.initials: C
authors.lastname: Darrin Hulsey
authors.affiliation: Department of Biological Sciences, University of New Orleans, 2000 Lakeshore Drive, New Orleans, LA 70148, USA.
authors.forename: Johel
authors.initials: J
authors.lastname: Chaves-Campos
authors.affiliation: Laboratorio de Genética para la Conservación, Centro de Investigaciones Biológicas del Noroeste, P.O. Box 128, La Paz, B.C.S., Mexico. Electronic address: fgarciadl@cibnor.mx.
authors.forename: Francisco J
authors.initials: FJ
authors.lastname: García de Leon
authors.affiliation: Department of Biological Sciences, University of New Orleans, 2000 Lakeshore Drive, New Orleans, LA 70148, USA.
authors.forename: Steven G
authors.initials: SG
authors.lastname: Johnson
mesh_terms: D000818:Animals; D001499:Bayes Theorem; D005075:Biological Evolution; D059552:Caves; D060126:Characidae / Q000145:classification* / Q000235:genetics; D004272:DNA, Mitochondrial / Q000235:genetics; D016013:Likelihood Functions; D008800:Mexico; D008957:Models, Genetic; D010802:Phylogeny; D058974:Phylogeography; D020641:Polymorphism, Single Nucleotide; D017422:Sequence Analysis, DNA
chemical_list: D004272:DNA, Mitochondrial
keywords: Astyanax mexicanus; Cave; Mexico; Phenotypic regression; Phylogeny; Phylogeography