{"publisher":"Society for the Study of Evolution","year":"1986","publist_id":"1724","date_created":"2018-12-11T12:08:14Z","user_id":"ea97e931-d5af-11eb-85d4-e6957dddbf17","volume":40,"oa_version":"None","intvolume":"        40","status":"public","acknowledgement":"We are grateful to J. Mitton and W. P. Hall for their suggestions and help with earlier versions of the statistical analysis. The manuscript was much improved by the helpful comments of Dorothy Currie, Gunther Gollmann, Godfrey Hewitt, Julian MacLean, and Jim Mallet. Thanks are also due to Tina Tsang for her careful typing. This work was supported by  the Exchange Agreement between the Polish Academy of Sciences and the Royal Society, and by grants from the Polish Academy of Sciences (project MR-II/6), the Royal Society, the Nuffield Foundation, and the  Science and Engineering Research Council. ","title":"Genetic analysis of a hybrid zone between the fire-bellied toads Bombina bombina and B. variegata, near Cracow in Southern Poland","quality_controlled":"1","publication_identifier":{"issn":["0014-3820"],"eissn":["1558-5646"]},"date_updated":"2022-01-31T15:31:37Z","month":"01","article_processing_charge":"No","page":"1141 - 1159","doi":"10.1111/j.1558-5646.1986.tb05740.x","day":"01","publication":"Evolution; International Journal of Organic Evolution","author":[{"first_name":"Jacek","last_name":"Szymura","full_name":"Szymura, Jacek"},{"orcid":"0000-0002-8548-5240","last_name":"Barton","first_name":"Nicholas H","id":"4880FE40-F248-11E8-B48F-1D18A9856A87","full_name":"Barton, Nicholas H"}],"type":"journal_article","abstract":[{"text":"The fire-bellied toads Bombina bombina and B. variegata differ extensively in biochemistry, morphology, and behavior. We use a survey of five diagnostic enzyme loci across the hybrid zone near Cracow in Southern Poland to estimate the dispersal rate, selection pressures, and numbers of loci which maintain this zone. The enzyme clines coincide closely with each other and with morphological and mitochondrial DNA clines. Although the zone lies on a broad transition between environments suitable for bombina and variegata, the close concordance of diverse characters, together with increased aberrations and mortality in hybrids, suggest that the zone is maintained largely by selection against hybrids. There are strong “linkage disequilibria” between each pair of (unlinked) enzyme loci (R̄ = 0.129 [2-unit support limits: 0.119–0.139]). These are probably caused by gene flow into the zone, and they give an estimate of dispersal (σ = 890 [790–940] m gen−½). The clines are sharply stepped, with most of the change occurring within 6.15 (5.45–6.45) km, but with long tails of introgression on either side. This implies that the effective selection pressure on each enzyme marker (due largely to disequilibrium with other loci) is s* = 0.17 (0.159–0.181) at the center but that the selection acting directly on the enzyme loci is weak or zero (se < 0.0038). The stepped pattern implies a barrier to gene flow of 220 (48–415) km. This would substantially delay neutral introgression but would have little effect on advantageous alleles; the two taxa need not evolve independently. Strong selection is needed to maintain such a barrier: hybrid populations must have their mean fitness reduced by a factor of 0.65 (0.60–0.77). This selection must be spread over a large number of loci to account for the concordant patterns and the observed cline widths (N = 300 [80–2,000]).","lang":"eng"}],"language":[{"iso":"eng"}],"_id":"4321","extern":"1","citation":{"apa":"Szymura, J., &#38; Barton, N. H. (1986). Genetic analysis of a hybrid zone between the fire-bellied toads Bombina bombina and B. variegata, near Cracow in Southern Poland. <i>Evolution; International Journal of Organic Evolution</i>. Society for the Study of Evolution. <a href=\"https://doi.org/10.1111/j.1558-5646.1986.tb05740.x\">https://doi.org/10.1111/j.1558-5646.1986.tb05740.x</a>","ista":"Szymura J, Barton NH. 1986. Genetic analysis of a hybrid zone between the fire-bellied toads Bombina bombina and B. variegata, near Cracow in Southern Poland. Evolution; International Journal of Organic Evolution. 40, 1141–1159.","chicago":"Szymura, Jacek, and Nicholas H Barton. “Genetic Analysis of a Hybrid Zone between the Fire-Bellied Toads Bombina Bombina and B. Variegata, near Cracow in Southern Poland.” <i>Evolution; International Journal of Organic Evolution</i>. Society for the Study of Evolution, 1986. <a href=\"https://doi.org/10.1111/j.1558-5646.1986.tb05740.x\">https://doi.org/10.1111/j.1558-5646.1986.tb05740.x</a>.","ama":"Szymura J, Barton NH. Genetic analysis of a hybrid zone between the fire-bellied toads Bombina bombina and B. variegata, near Cracow in Southern Poland. <i>Evolution; International Journal of Organic Evolution</i>. 1986;40:1141-1159. doi:<a href=\"https://doi.org/10.1111/j.1558-5646.1986.tb05740.x\">10.1111/j.1558-5646.1986.tb05740.x</a>","short":"J. Szymura, N.H. Barton, Evolution; International Journal of Organic Evolution 40 (1986) 1141–1159.","mla":"Szymura, Jacek, and Nicholas H. Barton. “Genetic Analysis of a Hybrid Zone between the Fire-Bellied Toads Bombina Bombina and B. Variegata, near Cracow in Southern Poland.” <i>Evolution; International Journal of Organic Evolution</i>, vol. 40, Society for the Study of Evolution, 1986, pp. 1141–59, doi:<a href=\"https://doi.org/10.1111/j.1558-5646.1986.tb05740.x\">10.1111/j.1558-5646.1986.tb05740.x</a>.","ieee":"J. Szymura and N. H. Barton, “Genetic analysis of a hybrid zone between the fire-bellied toads Bombina bombina and B. variegata, near Cracow in Southern Poland,” <i>Evolution; International Journal of Organic Evolution</i>, vol. 40. Society for the Study of Evolution, pp. 1141–1159, 1986."},"article_type":"original","publication_status":"published","date_published":"1986-01-01T00:00:00Z"}