DOI: 10.5061/dryad.rfj6q57jx
title: Data from: Genomic divergence, demographic histories, and male territorial response reveal asymmetric reproductive barriers in allopatric eastern versus western Nashville warbler subspecies (<em>Leiothlypis ruficapilla</em>)

description: In song-learning birds, vocalizations are species recognition signals and
 may act as premating reproductive barriers; for allopatric taxa, testing
 how the signals can influence the speciation processes is much more
 challenging. The current study aims to understand genomic divergence and
 species recognition via songs in two allopatric subspecies of Nashville
 warbler (Leiothlypis ruficapilla ruficapilla vs. Leiothlypis ruficapilla
 ridgwayi), whose populations are east and west of the Great Plains. We
 compared their songs to examine the objective acoustic differences, as
 well as performed playback experiments to assess their reciprocal
 behavioral responses. Our results suggest an asymmetric barrier, where the
 eastern L. r. ruficapilla discriminates between the two songs, but the
 western L. r. ridgwayi does not. Using whole-genome sequencing, we also
 examined the extent of genomic divergence and estimated the demographic
 history to uncover both recent and historical demographic changes. We
 identified dozens of highly differentiated regions in the genome, as well
 as fluctuations in historical effective population sizes that indicate
 independent demographic trajectories and their separation during the
 Pleistocene. To put the magnitude of divergence between L. ruficapilla
 subspecies into context, we also applied the same genomic analyses to two
 additional eastern-western pairs, Setophaga virens vs. Setophaga townsendi
 and Setophaga coronata coronata vs. Setophaga coronata auduboni, which
 have also undergone previous analyses of vocalization and song playbacks,
 but have overlapping ranges. Our findings provide insights into the role
 of vocalizations in defining each pair’s relationship and the important
 legacy of isolation during the Pleistocene on each of their genomes.
description: # Data from: Genomic divergence, demographic histories, and male
 territorial response reveal asymmetric reproductive barriers in allopatric
 eastern versus western Nashville warbler subspecies (*Leiothlypis
 ruficapilla*)
 [https://doi.org/10.5061/dryad.rfj6q57jx](https://doi.org/10.5061/dryad.rfj6q57jx) ## Description of the data and file structure ### Files and variables #### File: May2023_E_Nashville_playback_analysis.csv **Description:** Playback experiments on *Leiothlypis ruficapilla ruficapilla* (eastern Nashville Warbler), used in analysis comparing response towards song of the same subspecies (sympatric) vs. song of the western subspecies (allopatric). Each individual is either in the sympatric trial or the allopatric trial, never both. Data collected by LP, MM, and MB in 2023. ##### Variables * Record_Number: Unique identification of the individual * Date: Date when data was collected * Country: Country in which data was collected * Location: Name of the general area in which data was collected * Latitude: Latitude of the location at which data was collected * Longitude: Longitude of the location at which data was collected * Elevation_in_m: Elevation of the location at which data was collected, measured in meters (m) * Time: Time of day when the playback experiment started * Focal_Species: The taxa being experimented on * Allopatric_Species: The taxa allopatric to the taxa described in column Focal_Species * Trial: The trial group. "Sympatric" indicates that the trial used the song of the taxa described in column Focal_Species, "Allopatric" indicates that the trial used the song the the taxa described in column Allopatric_Species. * Track: The specific recording used in the trial from the song bank. The song bank consists of 12 possible recordings for each trial group (total: 24), sourced from the Macaulay Library ([https://www.macaulaylibrary.org/](https://www.macaulaylibrary.org/)); the recording used in each instance was determined randomly. * Before_approach_in_m: The horizontal distance from the experimental audio speaker to where the individual perches before the trial started, measured in meters (m) * Closest_approach_in_m: The horizontal distance from the experimental audio speaker to the closest perch of the individual during the 5-minute trial, measured in meters (m) * Sing_back: Whthe ether indisangal sung in response to the played recording, yes (Y), no (N), or not applicable/could not observe (NA) * Number_of_songs: How many times the individual sang in response to the played recording; if Sing_back is N or NA, the value in this column is NA. Addendum at the bottom of the dataset: the Macaulay ID of the song recordings in the column Track. #### File: W_Nashville_playback.csv **Description:** Playback experiments on *Leiothlypis ruficapilla ridgwayi* (western Nashville Warbler), used in analysis comparing response towards song of the same subspecies (sympatric) vs. song of the eastern subspecies (allopatric). Each individual was in both the sympatric trthe ial and allopatric trials. Data collected by BF, Ph.D., who shared the access and permission to use with the authors. ##### Variables * Day: Day when data was collected * Month: Month when data was collected * Year: Year when data was collected * Country: Country in which data was collected * Site: Name of the larger area in which data was collected * Location: Name of the general area in which data was collected * GPS_lat: Latitude of the location at which data was collected * GPS_long: Longitude of the location at which data was collected * Number: Unique identification of the individual * FocalSpecies: The taxa being experimented on * AllopatricSpecies: The taxa allopatric to the taxa described in column FocalSpecies * time: Time of day when the playback experiment started * Order: Which was done for experimentation on the same individual * Trial: The trial group. "Sympatric" indicates that the trial used the song of the taxa described in column FocalSpecies, "Allopatric" indicates that the trial used the song the the taxa described in column AllopatricSpecies. * Track: The specific recording used in the trial, sourced from the Macaulay Library ([https://www.macaulaylibrary.org/](https://www.macaulaylibrary.org/)) or Xenocanto ([https://xeno-canto.org/](https://xeno-canto.org/)) * DistanceFromSpeakerBeforePlayback: The horizontal distance from the experimental audio speaker to where the individual perches before the trial started, measured in meters (m) * latency_approach: Time it took for the individual to approach the speaker, measured in seconds (s) * close_approach: The horizontal distance from the experimental audio speaker to the closest perch of the individual during the 5-minute trial, measured in meters (m) * close_approach_bin: A binary measure of close_approach, whether the bird approached to within 15m, yes (1) or no (0) * latency_voc: Time it took the bird to vocalize after the trial started, measured in seconds (s) * songs: How many times the individual sang in response to the played recording. * calls: How many times the individual calls in response to the played recording.