Evidence for the Pleistocene Arc Hypothesis from genome-wide SNPs in a Neotropical dry forest specialist, the Rufous-fronted Thornbird (Furnariidae:Phacellodomus rufifrons)

Author(s)

Corbett, Eamon C. ^{[1, 2, 3, 4]} ; Bravo, Gustavo A. ^{[1, 2]} ; Schunck, Fabio ^[5] ; Naka, Luciano N. ^{[1, 2, 6]} ; Silveira, Luis F. ^[5] ; Edwards, Scott V. ^{[1, 2]}

Affiliation

^[1] Harvard Univ, Museum Comparat Zool, Cambridge, MA 02138 - USA

^[2] Harvard Univ, Dept Organism & Evolutionary Biol, Cambridge, MA 02138 - USA

^[3] Louisiana State Univ, Museum Nat Sci, Baton Rouge, LA 70803 - USA

^[4] Louisiana State Univ, Dept Biol Sci, Baton Rouge, LA 70803 - USA

^[5] Univ Sao Paulo, Museu Zool, Secao Aves, Sao Paulo - Brazil

^[6] Univ Fed Pernambuco, Dept Zool, Recife, PE - Brazil

• Document type: Journal article
• Source: Molecular Ecology; v. 29, n. 22, p. 4457-4472, NOV 2020.
• Web of Science Citations: 1

Abstract

South American dry forests have a complex and poorly understood biogeographic history. Based on the fragmented distribution of many Neotropical dry forest species, it has been suggested that this biome was more widely distributed and contiguous under drier climate conditions in the Pleistocene. To test this scenario, known as the Pleistocene Arc Hypothesis, we studied the phylogeography of the Rufous-fronted Thornbird (Phacellodomus rufifrons), a widespread dry forest bird with a disjunct distribution closely matching that of the biome itself. We sequenced mtDNA and used ddRADseq to sample 7,167 genome-wide single-nucleotide polymorphisms from 74P. rufifronsindividuals across its range. We found low genetic differentiation over two prominent geographic breaks - particularly across a 1,000 km gap between populations in Bolivia and Northern Peru. Using demographic analyses of the joint site frequency spectrum, we found evidence of recent divergence without subsequent gene flow across those breaks. By contrast, parapatric morphologically distinct populations in northeastern Brazil show high genetic divergence with evidence of recent gene flow. These results, in combination with our paleoclimate species distribution modelling, support the idea that currently disjunct patches of dry forest were more connected in the recent past, probably during the Middle and Late Pleistocene. This notion fits the major predictions of the Pleistocene Arc Hypothesis and illustrates the importance of comprehensive genomic and geographic sampling for examining biogeographic and evolutionary questions in complex ecosystems like Neotropical dry forests. (AU)

• FAPESP's process: 17/23548-2 - Evaluation, recovering and conservation of endangered animal species from the Pernambuco Centre of Endemism
• Grantee: Luís Fábio Silveira
• Support Opportunities: BIOTA-FAPESP Program - Thematic Grants
• FAPESP's process: 18/20249-7 - Origin and evolution of the avifauna at the highland forests in Northeastern Brazil: understanding the past connections between Amazon and Atlantic Forest
• Grantee: Luís Fábio Silveira
• Support Opportunities: Regular Research Grants