DNA barcodes highlight the role of glacial cycles on avian diversification and speciation in southern South America

• Autores: Lijtmaer, Dario A; Bukowski, Belen; Lavinia, Pablo D.; Casale, Agustin I; Fracas, Pablo A; Campagna, Leonardo; Tubaro, Pablo L
• Año de publicación: 2024
• Idioma: inglés
• Tipo de recurso: documento de conferencia
• Materia: Ciencias Exactas y Naturales; dna barcodes; birds; patagonia; diversification; Ciencias Exactas y Naturales
• Institución: Universidad Nacional de Río Negro

Fil: Lijtmaer Dario A. Museo Argentino de Ciencias Naturales "Bernardino Rivadavia", CABA, Argentina
Fil: Bukowski Belen. Museo Argentino de Ciencias Naturales "Bernardino Rivadavia", CABA, Argentina
Fil: Lavinia Pablo D. Laboratorio de Investigación y Conservación de la Biodiversidad (UNRN-InCoBIO), Universidad Nacional de Río Negro, Viedma, Argentina; Universidad Nacional de Río Negro, CIT Río Negro (UNRN-CONICET), Viedma, Argentina
Fil: Casale Agustin I. Museo Argentino de Ciencias Naturales "Bernardino Rivadavia", CABA, Argentina
Fil: Fracas Pablo A. Museo Argentino de Ciencias Naturales "Bernardino Rivadavia", CABA, Argentina
Fil: Campagna Leonardo. Cornell Lab of Ornithology, Ithaca, NY, Estados Unidos
Fil: Tubaro Pablo L. Museo Argentino de Ciencias Naturales "Bernardino Rivadavia", CABA, Argentina
Introduction: Glacial cycles have been key for speciation in the Nearctic, but they had a milder effect in most of the Neotropics. We are using DNA barcodes as the source of mitochondrial DNA, complemented with nuclear genomic data, colour and vocalizations, to study the relevance of glacial cycles in southern South America at different geographic and taxonomic scales. Methods: We analyzed over 9000 avian DNA barcode sequences belonging to more than 2000 species of birds of the Americas for a large-scale evaluation of their evolutionary patterns in the Andean-Patagonian region. We then studied in detail three species broadly distributed in the Neotropics with a focus on their southern populations: the Southern Lapwing (Vanellus chilensis), the House Wren (Troglodytes aedon) and the Rufous-collared Sparrow (Zonotrichia capensis). Results: The analysis of closely related species showed that the Andean-Patagonian region has a higher proportion of recently diverged species (less COI genetic distance) and presents less phylogeographic structure than the rest of the Neotropics, suggesting a relevant role of glaciations. This role was also evident in the detailed analyses of the three focal species. All had lineages endemic to Patagonia, although with differences in the timing of their separation, and the Southern Lapwing and the Rufous-collared Sparrow were also differentiated in plumage colouration or song. In the House Wren, the colonization of the Malvinas Islands and the lack of further gene flow with continental Patagonia led to speciation in the archipelago. Finally, northward postglacial expansions from Patagonia led to secondary contact with gene flow, resulting in intermediate colouration or songs in the three species. Conclusion: This study highlights the relevance of glaciations for avian diversification and speciation in southern South America and the role of DNA barcoding for the initial screening and posterior study of evolutionary patterns.