Selected song data for four Old world leaf warbler species

Measurements of song duration, number of total song elements and number of different song elements for Phylloscopus xanthoschistos, Seicercus whistleri, Seicercus burkii and Seicercus affini

R code

R code for all analyse

MOESM1 of Subspecific variation in sperm morphology and performance in the Long-tailed Finch (Poephila acuticauda)

Additional file 1. Relative testes mass in the Long-tailed Finch

ZBFI Sperm Heatwave data

This file containes all the data to run the main analysis and create figures that are described in the electronic supplementary R code file. Fowlers Gap 2014-2017 temperature data used in paper is also provided

Supplementary data

This 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

S3 Expanded statistical output. from Experimental heatwaves negatively impact sperm quality in the zebra finch

For sexually reproducing species, functionally competent sperm are critical to reproduction. While high atmospheric temperatures are known to influence the timing of breeding, incubation and reproductive success in birds, the effect of temperature on sperm quality remains largely unexplored. Here, we experimentally investigated the impact of ecologically relevant extreme temperatures on cloacal temperature and sperm morphology and motility in zebra finches <i>Taeniopygia guttata</i>. We periodically sampled males exposed to 30 or 40°C temperatures daily for 14 consecutive days. Following a 12-day (23°C) recovery period, birds were again exposed to heat, but under the alternate treatment (e.g. birds initially exposed to 40°C were exposed to 30°C). Elevated temperatures led to an increase in cloacal temperature and a reduction in the proportion of sperm with normal morphology; though these effects were most notable under 40°C conditions and were influenced by the duration of heat exposure and prior exposure to high temperature. Our findings highlight the potential role of temperature in determining male fertility in birds, and perhaps also in constraining the timing of avian breeding. Given the increased frequency of heatwaves in a warming world, our results suggest the need for further work on climatic influences on sperm quality and male fertility

Pyrrhula pyrrhula sperm motility

Motility measures of individual sperm tracks analysed by Computer Assisted Sperm Ananlysis (CASA). The file lists the sperm tracks from 11 male Eurasian bullfinches (P. pyrrhula) with details of sampling locality and date. (Raw data file for Table 2 in the paper

Rowe et al. sperm morphology data

Data on sperm morphology (i.e. sperm length) for males used in the comparative study of sperm evolutionary rate

Measurements of individual spermatozoa in Azores and Eurasian bullfinches

Measurements of head and flagellum length in 10 spermatozoa per male in 11 Azores bullfinches (P. murina) and 13 Eurasian bullfinches (P. pyrrhula) with details of sampling locality and date. (Raw data file for Table 1 in the paper

Sperm measurements (morphology and velocity) of two Passer species

Included in this data set are three .csv files containing data, one .xlsx file with information on the naming of columns in the data files (information for each data file is in a separate tab in the .xlsx file), and R code. However, this R script should be sufficient to understand exactly how analyses were performed. Justification for analysis decisions is indicated in the manuscript