Table S1 A sample of published studies on extra-pair paternity (EPP) showing the range in the percentage of genotyped extra-pair young (EPY) that were assigned a sire (% EPY sires), the percentage of all chicks that were EPY (% EPY) and the total number of chicks sampled (n). Studies are listed in ascending order of % EPY that were assigned sires. The current study assigned sires to 98% of EPY (with 95% individual-level confidence), 28% EPY and n=2207 and therefore constitutes one of the largest comprehensive paternity assignment yet achieved. Species Study % EPY sires % EPY n Seaside sparrow (Ammodramus maritimus) Hill & Post 2005 0 11 47 Common yellowthroats (Geothlypis trichas) Garvin et al. 2006 13 20 284 American redstart (Setophaga ruticilla) Kappes et al. 2009 39 44 81 Tree swallow (Tachycineta bicolour) Bitton et al. 2007 42 35 216 Black-capped chickadee (Poecile atricapillus) - Reudink et al. 2006 45 26 477 Pied flycatcher (Ficedula hypoleuca) Lehtonen et al. 2009 47 4 857 Tree swallow (Tachycineta bicolour) Stapleton et al. 2007 49 47 502 American redstart (Setophaga ruticilla) Reudink et al. 2009 49 33 135 Carolina chickadee (Poecile carolinensis) hybrids Moustached warbler (Acrocephalus melanopogon) Blomqvist et al. 2005 52 27 44 Blue tit (Cyanistes caeruleus) Charmantier et al. 2004 52 18 1332 Acadian flycatcher (Empidonax virescens) Woolfenden et al. 2005 53 41 133 Black-throated blue warbler (Dendroica caerulescens) Webster et al. 2001 54 23 413 Coal tit (Periparus ater) Schmoll et al. 2007 65 28 1945 Blue tit (Cyanistes caeruleus) Foerster et al. 2003 72 16 2452 Scarlet rosefinch (Carpodacus erythrinus) Albrecht et al. 200 73 18 266 Bluethroat (Luscinia s. svecica) Fossøy et al. 2007 74 26 1032 Eastern kingbird (Tyrannus tyrannus) Dolan et al. 2007 79 47 264 Dusky warbler (Phylloscopus fuscatus) Forstmeier et al. 2002 82 45 195 Reed bunting (Emberiza schoeniclus) Bouwman et al. 2006 83 51 501 Common yellowthroat (Geothlypis trichas) Whittingham & Dunn 2005 83 26 93 House wren (Troglodytes aedon) Whittingham & Dunn 2005 88 10 584 Savannah sparrow (Passerculus sandwichensis) Freeman-Gallant et al. 2005 92 47 411 Great reed warbler (Acrocephalus arundinaceus) Hasselquist et al. 1995 100 3 553 Barn swallow (Hirundo rustica erythrogaster) Kleven et al. 2006 100 31 391 Seychelles warbler (Acrocephalus sechellensis) Richardson et al. 2001 100 38 59 House martin (Delichon urbicum) Whittingham & Lifjeld 1995 100 29 38 References Albrecht T, Schnitzer J, Kreisinger J, Exnerova A, Bryja J, Munclinger P (2007) Extrapair paternity and the opportunity for sexual selection in long-distant migratory passerines. 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