DOI: 10.5061/dryad.rj25q
title: Data from: Early diversification of sperm size in the evolutionary history of the old world leaf warblers (Phylloscopidae)

description: Sperm morphological traits are highly variable among species and are
 commonly thought to evolve by post-copulatory sexual selection. However,
 little is known about the evolutionary dynamics of sperm morphology, and
 whether rates of evolutionary change are variable over time and among
 taxonomic groups. Here, we examine sperm morphology from 21 species of Old
 World leaf warblers (Phylloscopidae), a group of generally dull, sexually
 monochromatic birds, which are known to have high levels of extra-pair
 paternity. We found that sperm length differs markedly across species,
 spanning about 40% of the range observed across a larger selection of
 passerine birds. Furthermore, we found strong support for an ‘early-burst’
 model of trait evolution, implying that the majority of divergence in
 sperm length has occurred early in the evolutionary history of this clade
 with subsequent evolutionary stasis. This large early divergence matches
 the early divergence reported in ecological traits (i.e. body size and
 feeding behaviour). Our findings demonstrate that rates of evolution in
 sperm morphology can change over time in passerine taxa, and that
 evolutionary stasis in sperm traits can occur even in species exhibiting
 characteristics consistent with moderate-to-high levels of sperm
 competition. It remains a major challenge to identify the selection
 mechanisms and possible constraints responsible for these variable rates
 of sperm evolution.
description: Supplementary
 dataThis data file contains
 the following information: Supplement S1 Sampling dates and locations for
 Old World leaf warbler males used in the analyses with accession numbers
 for Natural History Museum Oslo (NHMO). Supplement S2 Summary of sperm
 morphology traits (head length, midpiece length, flagellum length and
 total length) for 21 species of Old World leaf warblers along with
 co-efficient of variation in total sperm length within and among males,
 the values for the latter adjusted for small sample sizes are also shown.
 Supplement S3 Sperm morphology measurements (head length, midpiece length,
 flagellum length and total length) for all the warbler males included in
 this study. Supplement S4 Combined testes mass data along with the sources
 for the data and calculations of the % body mass made accounted for by
 testes mass for ten of the Old World leaf warbler species included in this
 study. Supplement S5 Testes dimensions data for seven Old World leaf
 warbler species from the Field Museum of Natural History and California
 Academy of Sciences along with the locations and dates of data collection.
 Supplement S6 Calculations of combined testes mass (CTM, sum of left and
 right testes mass) from the testes dimensions for seven Old World leaf
 warbler species. Supplement S7 Genbank accession numbers for the genes
 used to reconstruct the Old World leaf warbler phylogeny used in our
 study. Supplement S8 Results of a phylogenetic generalized least squares
 analysis (PGLS) of standard deviation of (log) total sperm length against
 mid-latitude and (log) total sperm length, showing results similar to
 those obtained using CVam as the dependent variable. Supplement S9 Data on
 combined testes mass and extra-pair paternity for passerine bird species
 other than the Old World leaf warblers.Supplementaryinfo4Jan2016.xlsxPhylogeny of study speciesPhylogeny of 21 species of Old World leaf warblers included in our study with one outgroup species in nexus file format.Phylloscopus02.treeXML file used in BEASTXML file used as input in BEAST to reconstruct the phylogeny used in this study.Phylloscopus02.xml