ELECTRONIC SUPPLEMENTARY MATERIAL

Sex-biased survival predicts adult sex ratio variation in wild birds

Tamás Székely1,2,*, András Liker3,4, Robert P. Freckleton3, Claudia Fichtel2 and Peter M. Kappeler2

1 Biodiversity Laboratory, Department of Biology and Biochemistry, University of Bath, Bath BA2 7AY, UK

2 Behavioral Ecology & Sociobiology Unit, German Primate Center (DPZ), Kellnerweg 4, D - 37077 Göttingen, Germany

3 Department of Animal and Plant Sciences, Alfred Denny Building, University of Sheffield, Western Bank, Sheffield S10 2TN, UK

4 Department of Limnology, University of Pannonia, PO Box 158, 8201 Veszprém, Hungary

* Correspondence should be addressed to T.S. ()

Supplementary figure S1. Frequency distribution of sex ratios at (a) hatching, (b) fledging, and (c) adults in birds (n = 83, 86 and 187 species, respectively). The mean hatching sex ratios and adult sex ratios are significantly different from 0.5 (hatching sex ratio: mean ± SE = 0.517 ± 0.01, one sample t-test with phylogenetic control, t = 3.3, P = 0.002; adult sex ratio: 0.544± 0.01, t = 7.2, P < 0.001), whereas fledging sex ratio does not differ from 0.5 (0.509 ± 0.01, t = 0.7, P = 0.489).

Supplementary figure S2. Frequency distribution of (a) hatching, (b) fledging, and (c) adult sex ratios in 24 species of birds where all three estimates are available. The means of these estimates are not different from 0.5 (hatching: mean ± SE = 0.517 ± 0.01, one sample t-test, t = 1.7, P = 0.102; fledging: 0.502 ± 0.01, t = 0.2, P = 0.815; adults: 0.493 ± 0.02, t = 0.4, P= 0.723).

Supplementary figure S3.Frequency distribution of annual adult mortalities in (a) males, (b) females, and (c) sex difference in mortality bias (female mortality – male mortality). n = 265 species in all panels. The mortality bias is significantly different from zero (0.046 ± 0.01, one sample t test with phylogenetic control, t = 20.2, P < 0.001).

Supplementary figure S4. Adult sex ratio in relation to number of individuals (log(N)) in (a) house sparrows (b = -0.0186, t = 1.356, P = 0.187, n = 28 estimates), and (b) in birds (b = -0.011, t = 1.097, P = 0.275, n = 109 species)

(a)

(b)

Supplementary table S1. Data set and data references. In the final accepted version of the manuscript, all raw data will be provided.

1

Species / Adult sex ratio / Hatching sex ratio / Fledging sex ratio / Sex-specific adult mortality / Mating system and parental care
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