{"status":"ok","message-type":"work","message-version":"1.0.0","message":{"indexed":{"date-parts":[[2026,4,24]],"date-time":"2026-04-24T03:37:24Z","timestamp":1777001844224,"version":"3.51.4"},"reference-count":103,"publisher":"Wiley","issue":"3","license":[{"start":{"date-parts":[[2026,3,14]],"date-time":"2026-03-14T00:00:00Z","timestamp":1773446400000},"content-version":"vor","delay-in-days":13,"URL":"http:\/\/creativecommons.org\/licenses\/by\/4.0\/"},{"start":{"date-parts":[[2026,3,1]],"date-time":"2026-03-01T00:00:00Z","timestamp":1772323200000},"content-version":"tdm","delay-in-days":0,"URL":"http:\/\/doi.wiley.com\/10.1002\/tdm_license_1.1"}],"funder":[{"DOI":"10.13039\/501100001871","name":"Funda\u00e7\u00e3o para a Ci\u00eancia e a Tecnologia","doi-asserted-by":"publisher","award":["2021.07890.BD"],"award-info":[{"award-number":["2021.07890.BD"]}],"id":[{"id":"10.13039\/501100001871","id-type":"DOI","asserted-by":"publisher"}]}],"content-domain":{"domain":["onlinelibrary.wiley.com"],"crossmark-restriction":true},"short-container-title":["Ecology and Evolution"],"published-print":{"date-parts":[[2026,3]]},"abstract":"<jats:title>ABSTRACT<\/jats:title>\n                  <jats:p>\n                    Hybrid zones offer valuable insights into evolutionary processes. In species with bimodal reproduction, hybridization can produce transitional phenotypes that may pinpoint the evolutionary pathways connecting distinct reproductive modes. The fire salamander (\n                    <jats:styled-content style=\"fixed-case\">\n                      <jats:italic>Salamandra salamandra<\/jats:italic>\n                    <\/jats:styled-content>\n                    ) is one of the two amphibians known to display bimodal viviparity, with populations exhibiting larviparity\u2014birth of free\u2010living aquatic larvae\u2014across most of its distribution, while pueriparity\u2014birth of fully developed terrestrial metamorphs\u2014is geographically restricted. These strategies differ in maternal investment, ontogeny, and offspring phenotype. Here, we investigate variation in reproductive modes and associated offspring body condition across a hybrid zone between two lineages,\n                    <jats:italic>S. s. gallaica<\/jats:italic>\n                    and\n                    <jats:italic>S. s. bernardezi,<\/jats:italic>\n                    that differ in reproductive (larviparous and pueriparous, respectively) and morphological traits (i.e., body size, head shape, and dorsal coloration). We aimed to characterize the spatial distribution of reproductive modes across the contact zone and explore potential fitness advantages of \u2018pure\u2019 and intermediate reproductive modes using differences in offspring body condition as an indirect proxy. We found a gradual and continuous shift in reproductive modes across the contact zone, with \u201cpure\u201d pueriparous mode in the north and larviparous in the south, and mixed reproductive modes in central populations, where hybrids appear to be viable and fertile. Offspring body condition varied significantly between reproductive modes, with offspring from mixed\u2010strategy females not only being viable but also exhibiting the highest body condition. This may result from reduced intra\u2010brood competition for matrotrophic resources, or alternatively, from increased sibling competition that favors offspring with higher performance. This system offers a unique opportunity to examine transitional viviparous forms in a natural context, providing an excellent model for understanding parity evolution, life\u2010history trade\u2010offs, and the evolutionary significance of reproductive shifts in vertebrates.\n                  <\/jats:p>","DOI":"10.1002\/ece3.73223","type":"journal-article","created":{"date-parts":[[2026,3,14]],"date-time":"2026-03-14T07:32:32Z","timestamp":1773473552000},"update-policy":"https:\/\/doi.org\/10.1002\/crossmark_policy","source":"Crossref","is-referenced-by-count":0,"title":["Clinal Variation in Reproductive Modes and Offspring Body Condition Across a Contact Zone of a Bimodal Viviparous Salamander"],"prefix":"10.1002","volume":"16","author":[{"ORCID":"https:\/\/orcid.org\/0000-0003-4392-2876","authenticated-orcid":false,"given":"Clara","family":"Figueiredo\u2010V\u00e1zquez","sequence":"first","affiliation":[{"name":"Departamento de Biologia da Faculdade de Ci\u00eancias da Universidade do Porto  Porto Portugal"},{"name":"CIBIO\/InBIO, Centro de Investiga\u00e7\u00e3o em Biodiversidade e Recursos Gen\u00e9ticos da Universidade do Porto Instituto de Ci\u00eancias Agr\u00e1rias de Vair\u00e3o  Vair\u00e3o Portugal"},{"name":"BIOPOLIS Program in Genomics, Biodiversity and Land Planning CIBIO  Vair\u00e3o Portugal"}]},{"ORCID":"https:\/\/orcid.org\/0000-0003-4015-9609","authenticated-orcid":false,"given":"Luc\u00eda","family":"Alarc\u00f3n\u2010R\u00edos","sequence":"additional","affiliation":[{"name":"CIBIO\/InBIO, Centro de Investiga\u00e7\u00e3o em Biodiversidade e Recursos Gen\u00e9ticos da Universidade do Porto Instituto de Ci\u00eancias Agr\u00e1rias de Vair\u00e3o  Vair\u00e3o Portugal"},{"name":"ECOEVO Lab, EE Forestal Universidad de Vigo  Pontevedra Spain"},{"name":"Departamento de Biolog\u00eda de Organismos y Sistemas, \u00c1rea de Zoolog\u00eda Universidad de Oviedo  Oviedo Spain"}]},{"ORCID":"https:\/\/orcid.org\/0000-0002-9483-5695","authenticated-orcid":false,"given":"Guillermo","family":"Velo\u2010Ant\u00f3n","sequence":"additional","affiliation":[{"name":"ECOEVO Lab, EE Forestal Universidad de Vigo  Pontevedra Spain"}]}],"member":"311","published-online":{"date-parts":[[2026,3,14]]},"reference":[{"key":"e_1_2_11_2_1","doi-asserted-by":"publisher","DOI":"10.1111\/j.1420\u20109101.2012.02599.x"},{"key":"e_1_2_11_3_1","doi-asserted-by":"publisher","DOI":"10.1111\/mec.13685"},{"key":"e_1_2_11_4_1","doi-asserted-by":"publisher","DOI":"10.1111\/mec.15639"},{"key":"e_1_2_11_5_1","doi-asserted-by":"publisher","DOI":"10.1111\/jzo.13194"},{"key":"e_1_2_11_6_1","doi-asserted-by":"publisher","DOI":"10.1007\/s11692\u2010019\u201009489\u20103"},{"key":"e_1_2_11_7_1","doi-asserted-by":"publisher","DOI":"10.1038\/s41598\u2010020\u201071609\u20103"},{"key":"e_1_2_11_8_1","doi-asserted-by":"publisher","DOI":"10.1093\/zoolinnean\/zlae071"},{"key":"e_1_2_11_9_1","doi-asserted-by":"publisher","DOI":"10.1655\/03\u201055"},{"key":"e_1_2_11_10_1","doi-asserted-by":"publisher","DOI":"10.1111\/mec.17736"},{"key":"e_1_2_11_11_1","doi-asserted-by":"publisher","DOI":"10.1146\/annurev.es.23.110192.001321"},{"issue":"3","key":"e_1_2_11_12_1","first-page":"333","article-title":"Hybridization Experiment Between Oviparous and Viviparous Strains of Lacerta vivipara: A New Insight Into the Evolution of Viviparity in Reptiles","volume":"52","author":"Arrayago M.\u2010J.","year":"1996","journal-title":"Herpetologica"},{"key":"e_1_2_11_13_1","doi-asserted-by":"publisher","DOI":"10.1093\/gbe\/evab288"},{"key":"e_1_2_11_14_1","doi-asserted-by":"publisher","DOI":"10.1111\/j.1558\u20105646.2009.00622.x"},{"key":"e_1_2_11_15_1","doi-asserted-by":"publisher","DOI":"10.1146\/annurev.es.16.110185.000553"},{"key":"e_1_2_11_16_1","doi-asserted-by":"publisher","DOI":"10.1111\/1365\u20102435.12233"},{"key":"e_1_2_11_17_1","doi-asserted-by":"publisher","DOI":"10.1655\/0733\u20101347(2007)20[131:SRAMOF]2.0.CO;2"},{"key":"e_1_2_11_18_1","doi-asserted-by":"publisher","DOI":"10.1002\/jmor.20272"},{"key":"e_1_2_11_19_1","doi-asserted-by":"publisher","DOI":"10.1002\/9780470015902.a0022851"},{"key":"e_1_2_11_20_1","doi-asserted-by":"publisher","DOI":"10.1111\/j.1525\u2010142X.2006.00141.x"},{"key":"e_1_2_11_21_1","doi-asserted-by":"publisher","DOI":"10.1016\/j.ympev.2020.107063"},{"key":"e_1_2_11_22_1","doi-asserted-by":"publisher","DOI":"10.1086\/695136"},{"key":"e_1_2_11_23_1","doi-asserted-by":"publisher","DOI":"10.1111\/mec.12577"},{"key":"e_1_2_11_24_1","doi-asserted-by":"publisher","DOI":"10.1007\/s00265\u2010014\u20101853\u20101"},{"key":"e_1_2_11_25_1","doi-asserted-by":"publisher","DOI":"10.1111\/bij.12478"},{"key":"e_1_2_11_26_1","doi-asserted-by":"publisher","DOI":"10.1038\/hdy.2015.54"},{"key":"e_1_2_11_27_1","doi-asserted-by":"publisher","DOI":"10.1111\/jbi.70046"},{"key":"e_1_2_11_28_1","doi-asserted-by":"publisher","DOI":"10.1163\/15685381\u201000003121"},{"key":"e_1_2_11_29_1","volume-title":"Genetics and the Origin of Species","author":"Dobzhansky T.","year":"1937"},{"key":"e_1_2_11_30_1","doi-asserted-by":"publisher","DOI":"10.1038\/s41467\u2010024\u201049464\u2010x"},{"key":"e_1_2_11_31_1","first-page":"147","volume-title":"Herpetologia Candiana","author":"Donaire\u2010Barroso D.","year":"2001"},{"key":"e_1_2_11_32_1","first-page":"125","article-title":"Preliminary Results on Optional Viviparity and Intrauterine Siblicide in Salamandra salamandra Populations From Northern Spain","volume":"4","author":"Dopazo H.","year":"1994","journal-title":"Mertensiella"},{"issue":"2","key":"e_1_2_11_33_1","first-page":"144","article-title":"Viviparity in Salamandra salamandra (Amphibia: Salamandridae): Adaptation or Exaptation?","volume":"56","author":"Dopazo H.","year":"2000","journal-title":"Herpetologica"},{"key":"e_1_2_11_34_1","doi-asserted-by":"publisher","DOI":"10.1073\/pnas.2302424120"},{"key":"e_1_2_11_35_1","doi-asserted-by":"publisher","DOI":"10.1086\/284411"},{"key":"e_1_2_11_36_1","first-page":"179","article-title":"Differences in Size at Birth and Brood Size Among Portuguese Populations of the Fire Salamander, Salamandra salamandra","volume":"13","author":"Eclair M. H. L.","year":"2003","journal-title":"Herpetological Journal"},{"key":"e_1_2_11_37_1","doi-asserted-by":"publisher","DOI":"10.1007\/s10682\u2010021\u201010114\u2010z"},{"key":"e_1_2_11_38_1","first-page":"7","article-title":"Viviparismo y distribuci\u00f3n de Salamandra salamadra bernardezi en el norte de Galicia","volume":"18","author":"Gal\u00e1n P.","year":"2007","journal-title":"Bolet\u00edn de la Asociaci\u00f3n Herpetol\u00f3gica Espa\u00f1ola"},{"key":"e_1_2_11_39_1","doi-asserted-by":"publisher","DOI":"10.1111\/j.0014\u20103820.2003.tb00221.x"},{"issue":"2","key":"e_1_2_11_40_1","first-page":"105","article-title":"The Effect of Hybrids on Phylogenomic Delimitation of Subspecies in a Highly Polymorphic Amphibian Group, Salamandra","volume":"60","author":"Gippner S.","year":"2024","journal-title":"Salamandra"},{"key":"e_1_2_11_41_1","first-page":"443","volume-title":"Human Cognitive Processing","author":"Glynn D.","year":"2014"},{"key":"e_1_2_11_42_1","doi-asserted-by":"publisher","DOI":"10.1111\/j.1558\u20105646.2012.01715.x"},{"key":"e_1_2_11_43_1","doi-asserted-by":"publisher","DOI":"10.1111\/eva.12380"},{"key":"e_1_2_11_44_1","doi-asserted-by":"publisher","DOI":"10.1126\/science.256.5054.193"},{"key":"e_1_2_11_45_1","doi-asserted-by":"publisher","DOI":"10.1002\/(SICI)1097-010X(199811\/12)282:4\/5<507::AID-JEZ7>3.0.CO;2-0"},{"key":"e_1_2_11_46_1","first-page":"447","volume-title":"Reproductive Biology and Phylogeny of Urodela (Amphibia)","author":"Greven H.","year":"2003"},{"key":"e_1_2_11_47_1","doi-asserted-by":"publisher","DOI":"10.1038\/ncomms11271"},{"key":"e_1_2_11_48_1","doi-asserted-by":"publisher","DOI":"10.1038\/s41437\u2010019\u20100201\u20107"},{"key":"e_1_2_11_49_1","doi-asserted-by":"publisher","DOI":"10.1186\/s12983\u2010021\u201000403\u20102"},{"key":"e_1_2_11_50_1","doi-asserted-by":"publisher","DOI":"10.1111\/j.1365\u2010294X.2012.05583.x"},{"key":"e_1_2_11_51_1","doi-asserted-by":"publisher","DOI":"10.1086\/284211"},{"key":"e_1_2_11_52_1","doi-asserted-by":"publisher","DOI":"10.1038\/nature04403"},{"key":"e_1_2_11_53_1","doi-asserted-by":"publisher","DOI":"10.1038\/nature14181"},{"key":"e_1_2_11_54_1","doi-asserted-by":"publisher","DOI":"10.18637\/jss.v025.i01"},{"key":"e_1_2_11_55_1","volume-title":"Emmeans: Estimated Marginal Means, Aka Least\u2010Squares Means (Version 1.11.1)","author":"Lenth R. V.","year":"2025"},{"key":"e_1_2_11_56_1","doi-asserted-by":"publisher","DOI":"10.1038\/s41467\u2010022\u201034474\u20104"},{"issue":"2","key":"e_1_2_11_57_1","first-page":"73","article-title":"Identification of a Contact Zone Between Oviparous and Viviparous Common Lizards (Zootoca vivipara) in Central Europe: Reproductive Strategies and Natural Hybridization","volume":"46","author":"Lindtke D.","year":"2010","journal-title":"Salamandra"},{"key":"e_1_2_11_58_1","doi-asserted-by":"publisher","DOI":"10.1111\/mec.14019"},{"key":"e_1_2_11_59_1","doi-asserted-by":"publisher","DOI":"10.1111\/mec.15249"},{"key":"e_1_2_11_60_1","doi-asserted-by":"publisher","DOI":"10.21105\/joss.03139"},{"key":"e_1_2_11_61_1","doi-asserted-by":"publisher","DOI":"10.1670\/10\u2010292"},{"key":"e_1_2_11_62_1","doi-asserted-by":"publisher","DOI":"10.1111\/j.1466\u20108238.2011.00700.x"},{"key":"e_1_2_11_63_1","doi-asserted-by":"publisher","DOI":"10.1016\/j.ympev.2021.107347"},{"key":"e_1_2_11_64_1","doi-asserted-by":"publisher","DOI":"10.1007\/s00360\u2010011\u20100584\u20100"},{"key":"e_1_2_11_65_1","doi-asserted-by":"publisher","DOI":"10.1098\/rspb.2014.2272"},{"key":"e_1_2_11_66_1","doi-asserted-by":"publisher","DOI":"10.1038\/s41559\u2010016\u20100001"},{"key":"e_1_2_11_67_1","doi-asserted-by":"publisher","DOI":"10.1111\/j.1600\u20100706.2009.17643.x"},{"key":"e_1_2_11_68_1","unstructured":"Pinheiro J. D.Bates S.DebRoy D.Sarkar andR Core Team.2025.\u201cnlme: Linear and Nonlinear Mixed Effects Models (Version 3.1\u2013168) [Computer software].\u201dhttps:\/\/cran.r\u2010project.org\/web\/packages\/nlme\/index.html."},{"key":"e_1_2_11_69_1","doi-asserted-by":"publisher","DOI":"10.1046\/j.1420\u20109101.1998.11010063.x"},{"key":"e_1_2_11_70_1","unstructured":"R Core Team.2021.\u201cR: A language and environment for statistical computing. [Computer software].\u201dhttps:\/\/www.R\u2010project.org\/."},{"key":"e_1_2_11_71_1","doi-asserted-by":"publisher","DOI":"10.1111\/jeb.13047"},{"key":"e_1_2_11_72_1","doi-asserted-by":"publisher","DOI":"10.1038\/s41559\u2010021\u201001555\u20104"},{"key":"e_1_2_11_73_1","doi-asserted-by":"publisher","DOI":"10.1007\/s00442\u2010019\u201004398\u2010w"},{"key":"e_1_2_11_74_1","doi-asserted-by":"publisher","DOI":"10.1126\/science.1086949"},{"key":"e_1_2_11_75_1","doi-asserted-by":"publisher","DOI":"10.1007\/s11692\u2010013\u20109247\u20102"},{"issue":"6","key":"e_1_2_11_76_1","first-page":"189","article-title":"Miscellaneous Notes on the South American Water Snake Genus Helicops","volume":"1","author":"Rossman D.","year":"1973","journal-title":"HISS News\u2010Journal"},{"key":"e_1_2_11_77_1","doi-asserted-by":"publisher","DOI":"10.3389\/fenvs.2015.00001"},{"key":"e_1_2_11_78_1","doi-asserted-by":"publisher","DOI":"10.1371\/journal.pgen.1000930"},{"key":"e_1_2_11_79_1","doi-asserted-by":"publisher","DOI":"10.1002\/jez.b.22792"},{"key":"e_1_2_11_80_1","doi-asserted-by":"publisher","DOI":"10.1038\/nmeth.2019"},{"key":"e_1_2_11_81_1","doi-asserted-by":"publisher","DOI":"10.1016\/j.tree.2004.01.003"},{"key":"e_1_2_11_82_1","doi-asserted-by":"publisher","DOI":"10.2307\/1446988"},{"key":"e_1_2_11_83_1","doi-asserted-by":"publisher","DOI":"10.1111\/j.1558\u20105646.1990.tb05198.x"},{"key":"e_1_2_11_84_1","doi-asserted-by":"publisher","DOI":"10.1071\/ZO97023"},{"key":"e_1_2_11_85_1","doi-asserted-by":"publisher","DOI":"10.1098\/rspb.2015.1666"},{"key":"e_1_2_11_86_1","doi-asserted-by":"publisher","DOI":"10.1086\/409052"},{"key":"e_1_2_11_87_1","doi-asserted-by":"publisher","DOI":"10.1201\/b17961-16"},{"key":"e_1_2_11_88_1","doi-asserted-by":"publisher","DOI":"10.1006\/mpev.2000.0896"},{"key":"e_1_2_11_89_1","doi-asserted-by":"publisher","DOI":"10.1016\/j.tree.2015.04.010"},{"key":"e_1_2_11_90_1","doi-asserted-by":"publisher","DOI":"10.1111\/j.1558\u20105646.1987.tb05777.x"},{"key":"e_1_2_11_91_1","first-page":"91","article-title":"Variation in the Reproductive Strategies of Salamandra salamandra (Linnaeus, 1758) Populations in the Province of Gipuzkoa (Basque Country)","volume":"61","author":"Uotila E.","year":"2013","journal-title":"Munibe (Ciencias Naturales\u2010Natur Zientziak)"},{"key":"e_1_2_11_92_1","doi-asserted-by":"publisher","DOI":"10.1098\/rspb.2018.2737"},{"key":"e_1_2_11_93_1","doi-asserted-by":"publisher","DOI":"10.1073\/pnas.1921318117"},{"key":"e_1_2_11_94_1","doi-asserted-by":"publisher","DOI":"10.1111\/j.1439\u20100469.1998.tb00774.x"},{"key":"e_1_2_11_95_1","unstructured":"Velo\u2010Ant\u00f3n G. andD.Buckley.2015.\u201cSalamandra com\u00fan \u2013Salamandra salamandra(Linnaeus 1758).\u201dInEnciclopedia Virtual de los Vertebrados Espa\u00f1oles. Museo Nacional de Ciencias Naturales.http:\/\/www.vertebradosibericos.org\/anfibios\/salsal.html."},{"key":"e_1_2_11_96_1","doi-asserted-by":"publisher","DOI":"10.1163\/15685381\u2010bja10143"},{"key":"e_1_2_11_97_1","doi-asserted-by":"publisher","DOI":"10.1111\/j.1439\u20100469.2007.00420.x"},{"key":"e_1_2_11_98_1","doi-asserted-by":"publisher","DOI":"10.1038\/hdy.2011.91"},{"key":"e_1_2_11_99_1","doi-asserted-by":"publisher","DOI":"10.1038\/s41598\u2010021\u201088349\u20107"},{"key":"e_1_2_11_100_1","doi-asserted-by":"publisher","DOI":"10.1007\/s10682\u2010014\u20109720\u20100"},{"key":"e_1_2_11_101_1","doi-asserted-by":"publisher","DOI":"10.1111\/brv.12836"},{"key":"e_1_2_12_4_2_1","doi-asserted-by":"publisher","DOI":"10.18637\/jss.v067.i01"},{"key":"e_1_2_12_4_3_1","unstructured":"Hartig F. L.Lohse andM. d. S.leite.2024.\u201cDHARMa: Residual Diagnostics for Hierarchical (Multi\u2010Level\/Mixed) Regression Models (Version 0.4.7) [Computer Software].\u201dhttps:\/\/cran.r\u2010project.org\/web\/packages\/DHARMa\/index.html."},{"key":"e_1_2_12_4_4_1","doi-asserted-by":"publisher","DOI":"10.21105\/joss.03139"}],"container-title":["Ecology and Evolution"],"original-title":[],"language":"en","link":[{"URL":"https:\/\/onlinelibrary.wiley.com\/doi\/pdf\/10.1002\/ece3.73223","content-type":"application\/pdf","content-version":"vor","intended-application":"text-mining"},{"URL":"https:\/\/onlinelibrary.wiley.com\/doi\/full-xml\/10.1002\/ece3.73223","content-type":"application\/xml","content-version":"vor","intended-application":"text-mining"},{"URL":"https:\/\/onlinelibrary.wiley.com\/doi\/pdf\/10.1002\/ece3.73223","content-type":"unspecified","content-version":"vor","intended-application":"similarity-checking"}],"deposited":{"date-parts":[[2026,4,24]],"date-time":"2026-04-24T02:49:06Z","timestamp":1776998946000},"score":1,"resource":{"primary":{"URL":"https:\/\/onlinelibrary.wiley.com\/doi\/10.1002\/ece3.73223"}},"subtitle":[],"short-title":[],"issued":{"date-parts":[[2026,3]]},"references-count":103,"journal-issue":{"issue":"3","published-print":{"date-parts":[[2026,3]]}},"alternative-id":["10.1002\/ece3.73223"],"URL":"https:\/\/doi.org\/10.1002\/ece3.73223","archive":["Portico"],"relation":{},"ISSN":["2045-7758","2045-7758"],"issn-type":[{"value":"2045-7758","type":"print"},{"value":"2045-7758","type":"electronic"}],"subject":[],"published":{"date-parts":[[2026,3]]},"assertion":[{"value":"2025-08-14","order":0,"name":"received","label":"Received","group":{"name":"publication_history","label":"Publication History"}},{"value":"2026-02-20","order":2,"name":"accepted","label":"Accepted","group":{"name":"publication_history","label":"Publication History"}},{"value":"2026-03-14","order":3,"name":"published","label":"Published","group":{"name":"publication_history","label":"Publication History"}}],"article-number":"e73223"}}