DOI: 10.5061/dryad.9j616
title: Data from: Species-level divergences in multiple functional traits between the two endemic subspecies of Blue Chaffinches Fringilla teydea in Canary Islands

description: Background: One of the biggest challenges in avian taxonomy is the
 delimitation of allopatric species because their reproductive
 incompatibility cannot be directly studied in the wild. Instead,
 reproductive incompatibility has to be inferred from multiple, divergent
 character sets that indicate a low likelihood of allopatric populations
 amalgamating upon secondary contact. A set of quantitative criteria for
 species delimitation has been developed for avian taxonomy. Results: Here,
 we report a broad multi-trait comparison of the two insular subspecies of
 the Blue Chaffinch Fringilla teydea, endemic to the pine forests of
 Tenerife (ssp. teydea) and Gran Canaria (ssp. polatzeki) in the Canary
 Islands. We found that the two taxa were reciprocally monophyletic in
 their whole mitogenomes and two Z chromosome introns. The genetic distance
 in mitogenomes indicates around 1 Mya of allopatric evolution. There were
 diagnostic differences in body morphometrics, song and plumage reflectance
 spectra, whose combined divergence score (=11) exceeds the threshold level
 (=7) set for species delimitation by Tobias et al. (Ibis 152:724–746,
 2010). Moreover, we found a marked divergence in sperm lengths with little
 range overlap. Relatively long sperm with low intra- and intermale CV
 compared to other passerines suggest a mating system with high levels of
 sperm competition (extrapair paternity) in these taxa. Conclusion: The
 large and diagnostic divergences in multiple functional traits qualify for
 species rank, i.e., Tenerife Blue Chaffinch (Fringilla teydea) and Gran
 Canaria Blue Chaffinch (Fringilla polatzeki). We encourage a wider use of
 sperm traits in avian taxonomy because sperm divergences might signal
 reproductive incompatibility at the postcopulatory prezygotic stage,
 especially in species with sperm competition.
description: Morphological
 measurements of Blue ChaffinchesWing length, bill
 length, bill depth, tarsus length, body mass and tail length measurements
 for male and female Blue Chaffinches for the two taxa, teydea and
 polatzekiBiometrics.xlsxReflectance spectra for five plumage areas of teydea and polatzeki Blue ChaffinchesReflectance data given as the mean of five individual measurements for each of five body parts (back, median covert, crown, rump and throat) from five study skins of polatzeki and ten study skins of teydea Blue Chaffinches. Values are given in bins of 5 nm in the range of 300-700 nm.Individual means 5nm_dryad.xlsxSperm measurements of Blue ChaffinchesThe length (in micrometer) of sperm components (head, midpiece and tail) and total sperm length of polatzeki and teydea Blue Chaffinches. The identity of the measurer is also indicatedSperm measurements.xlsxLuscinia softwareAvailable on GitHubBlueChaffinch.luscdbA database of Blue Chaffinch song files used for analysis with the Luscinia software (available in GitHub at the link above). The database contains the raw sound files for the songs that were included in the analysis, the metadata about each individual recording, and the measurements of each sound file. Unzip the file "BlueChaffinch.luscdb.zip" to access the BlueChaffinch.luscdb directory.