Amazonian rivers are leaky barriers to gene flow in forest understory birds

Ever since Alfred Russel Wallace’s nineteenth-century observation that related terrestrial species are often separated on opposing riverbanks, major Amazonian rivers have been recognized as key drivers of speciation. However, rivers are dynamic entities whose widths and courses may vary through time. It thus remains unknown how effective rivers are at reducing gene flow and promoting speciation over long timescales. We fit demographic models to genomic sequence to reconstruct the history of gene flow in three pairs of avian taxa fully separated by different Amazonian rivers, and whose geographic ranges do not make contact in headwater regions. Models with gene flow were best fit, but still supported an initial period without any gene flow which ranged from 187,000 to over 959,000 years, suggesting that rivers are capable of initiating speciation through long stretches of allopatric divergence. Allopatry was followed by either bursts or prolonged episodes of gene flow that retarded genom..., These are model files used for fastSIMCOAL2. , , # Data from: Amazonian rivers are leaky barriers to gene flow in forest understory birds

[https://doi.org/10.5061/dryad.z34tmpgnr](https://doi.org/10.5061/dryad.z34tmpgnr)

Our paper estimates the role of gene flow between three pairs of avian taxa separated by Amazonian rivers. For each taxon pair, we fit 15 demographic models to the site frequency spectrum using fastSIMCOAL2 v27 (Excoffier, et al. 2013). Here we include the Site Frequency Spectra files (MODEL_MSFS.obs), demographic model description files (MODEL.tpl) and parameter files (MODEL.est) required to run fastSIMCOAL2 for model testing and parameter estimation.

## Description of the data and file structure

The zipped directory \"Site_Frequency_Spectra.zip\" contains three folders with the names of the three species analyzed. Inside each are two folders that contain the site frequency spectrum file (MODEL_MSFS.obs) for a two-population model (located in the directory “2POP”) and a three-population model (“3POP”). The SFS spec...