title: The role of river drainages in shaping the genetic structure of capybara populations.
abstract: The capybara, Hydrochoerus hydrochaeris, is an herbivorous rodent widely distributed throughout most of South American wetlands that lives closely associated with aquatic environments. In this work, we studied the genetic structure of the capybara throughout part of its geographic range in Argentina using a DNA fragment of the mitochondrial control region. Haplotypes obtained were compared with those available for populations from Paraguay and Venezuela. We found 22 haplotypes in 303 individuals. Hierarchical AMOVAs were performed to evaluate the role of river drainages in shaping the genetic structure of capybara populations at the regional and basin scales. In addition, two landscape genetic models, isolation by distance and isolation by resistance, were used to test whether genetic distance was associated with Euclidean distance (i.e. isolation by distance) or river corridor distance (i.e. isolation by resistance) at the basin scale. At the regional scale, the results of the AMOVA grouping populations by mayor river basins showed significant differences between them. At the basin scale, we also found significant differences between sub-basins in Paraguay, together with a significant correlation between genetic and river corridor distance. For Argentina and Venezuela, results were not significant. These results suggest that in Paraguay, the current genetic structure of capybaras is associated with the lack of dispersion corridors through permanent rivers. In contrast, limited structuring in Argentina and Venezuela is likely the result of periodic flooding facilitating dispersion.
authors.affiliation: Grupo de Estudios en Ecología de Mamíferos, Departamento de Ciencias Básicas, Universidad Nacional de Luján, Intersección Rutas 5 y 7, 6700, Luján, Buenos Aires, Argentina.|Comisión de Investigaciones Científicas (CIC) de la Provincia de Buenos Aires, Calle 526 entre 10 y 11, 1900, La Plata, Buenos Aires, Argentina.
authors.forename: María Soledad
authors.initials: MS
authors.lastname: Byrne
authors.affiliation: Laboratorio de Biodiversidad, Limnología y Biología de la Conservación, Instituto de Investigación e Ingeniería Ambiental (3iA), UNSAM, Av. 25 de Mayo y Francia, B1650HMP, General San Martín, Buenos Aires, Argentina.|GIEH, Departamento de Ecología, Genética y Evolución, FCEyN, UBA, Intendente Güiraldes 2160, C14288EGA, Buenos Aires, Argentina.|Consejo Nacional de Investigaciones Científicas y Técnicas (CONICET), Av. Rivadavia 1917, 1033AAJ, Buenos Aires, Argentina.
authors.forename: Rubén Darío
authors.initials: RD
authors.lastname: Quintana
authors.affiliation: Dirección de Fauna Silvestre, SAyDS, San Martín 451, C1004AAI, Buenos Aires, Argentina.
authors.forename: María Luisa
authors.initials: ML
authors.lastname: Bolkovic
authors.affiliation: Grupo de Estudios en Ecología de Mamíferos, Departamento de Ciencias Básicas, Universidad Nacional de Luján, Intersección Rutas 5 y 7, 6700, Luján, Buenos Aires, Argentina.|Consejo Nacional de Investigaciones Científicas y Técnicas (CONICET), Av. Rivadavia 1917, 1033AAJ, Buenos Aires, Argentina.|Laboratorio de Biología del Comportamiento, Instituto de Biología y Medicina Experimental (IBYME-CONICET), Vuelta de Obligado 2490, C1428ADN, Buenos Aires, Argentina.
authors.forename: Marcelo H
authors.initials: MH
authors.lastname: Cassini
authors.affiliation: Grupo de Estudios en Ecología de Mamíferos, Departamento de Ciencias Básicas, Universidad Nacional de Luján, Intersección Rutas 5 y 7, 6700, Luján, Buenos Aires, Argentina. nacho_tunez@yahoo.com.ar.|Consejo Nacional de Investigaciones Científicas y Técnicas (CONICET), Av. Rivadavia 1917, 1033AAJ, Buenos Aires, Argentina. nacho_tunez@yahoo.com.ar.
authors.forename: Juan Ignacio
authors.initials: JI
authors.lastname: Túnez
mesh_terms: D000818:Animals; D001118:Argentina; D004272:DNA, Mitochondrial / Q000032:analysis*; D055868:Floods; D010239:Paraguay; D045483:Rivers; D012377:Rodentia / Q000235:genetics*; D014687:Venezuela
chemical_list: D004272:DNA, Mitochondrial
keywords: HVRI; Hydrochoerus hydrochaeris; Mitochondrial DNA; River basins; South America