--- _id: '3673' abstract: - lang: eng text: The effect of a cline as a barrier to gene flow at closely linked, weakly selected loci is investigated using a continuous diffusion model. It is shown that a linked cline induces a step in the frequency of a neutral allele, which is proportional to the gradient in neutral allele frequency and to the inverse of the recombination rate. A barrier to dispersal or a local region of low abundance has a similar effect (Nagylaki, 1976). The cline will block the flow of neutral alleles over a region of chromosome roughly 2s/t map units long. However, a slightly advantageous allele will be little affected, and must be very tightly linked to be delayed for long. acknowledgement: "I would like to thank Dr G. M. Hewitt for stimulating discussions, and for his comments on the manuscript. This work was supported by the Natural Environmental Research Council.\r\n" article_processing_charge: No article_type: original author: - first_name: Nicholas H full_name: Barton, Nicholas H id: 4880FE40-F248-11E8-B48F-1D18A9856A87 last_name: Barton orcid: 0000-0002-8548-5240 citation: ama: Barton NH. Gene flow past a cline. Heredity. 1979;43(3):333-339. doi:10.1038/hdy.1979.86 apa: Barton, N. H. (1979). Gene flow past a cline. Heredity. Springer Nature. https://doi.org/10.1038/hdy.1979.86 chicago: Barton, Nicholas H. “Gene Flow Past a Cline.” Heredity. Springer Nature, 1979. https://doi.org/10.1038/hdy.1979.86. ieee: N. H. Barton, “Gene flow past a cline,” Heredity, vol. 43, no. 3. Springer Nature, pp. 333–339, 1979. ista: Barton NH. 1979. Gene flow past a cline. Heredity. 43(3), 333–339. mla: Barton, Nicholas H. “Gene Flow Past a Cline.” Heredity, vol. 43, no. 3, Springer Nature, 1979, pp. 333–39, doi:10.1038/hdy.1979.86. short: N.H. Barton, Heredity 43 (1979) 333–339. date_created: 2018-12-11T12:04:33Z date_published: 1979-12-01T00:00:00Z date_updated: 2021-12-15T15:16:50Z day: '01' doi: 10.1038/hdy.1979.86 extern: '1' intvolume: ' 43' issue: '3' language: - iso: eng main_file_link: - open_access: '1' url: https://www.nature.com/articles/hdy197986 month: '12' oa: 1 oa_version: Published Version page: 333 - 339 publication: Heredity publication_identifier: eissn: - 1365-2540 issn: - 0018-067X publication_status: published publisher: Springer Nature publist_id: '2710' quality_controlled: '1' scopus_import: '1' status: public title: Gene flow past a cline type: journal_article user_id: 8b945eb4-e2f2-11eb-945a-df72226e66a9 volume: 43 year: '1979' ... --- _id: '4336' abstract: - lang: eng text: "This paper investigates the dynamic behaviour of hybrid zones which are maintained by a balance between dispersal and selection against hybrids. In the first section it is shown that a hybrid zone involving a single locus can move in response to a selective imbalance between the two homozygotes, and also to variation in population density and dispersal rate. It can be trapped by natural barriers, and so an allele which is selected against when rare cannot advance, even if it is advantageous when common. The continuous model used in deriving these results is shown to be a good approximation to the stepping-stone model, provided that the cline contains several demes.\r\n\r\nThe effect of stochastic forces on multi-locus hybrid zones is then considered. An expression giving the shift in position after an arbitrary perturbation in gamete frequency is derived. Using this formula, it is found that sampling drift is negligible unless the zone includes few organisms and involves few loci. Random variations in population structure are the dominant force, and could allow considerable movement in an even environment. However, natural barriers can still trap hybrid zones, and so it is likely that they will remain roughly where they first formed." article_processing_charge: No article_type: original author: - first_name: Nicholas H full_name: Barton, Nicholas H id: 4880FE40-F248-11E8-B48F-1D18A9856A87 last_name: Barton orcid: 0000-0002-8548-5240 citation: ama: Barton NH. The dynamics of hybrid zones. Heredity. 1979;43(3):341-359. doi:10.1038/hdy.1979.87 apa: Barton, N. H. (1979). The dynamics of hybrid zones. Heredity. Springer Nature. https://doi.org/10.1038/hdy.1979.87 chicago: Barton, Nicholas H. “The Dynamics of Hybrid Zones.” Heredity. Springer Nature, 1979. https://doi.org/10.1038/hdy.1979.87. ieee: N. H. Barton, “The dynamics of hybrid zones,” Heredity, vol. 43, no. 3. Springer Nature, pp. 341–359, 1979. ista: Barton NH. 1979. The dynamics of hybrid zones. Heredity. 43(3), 341–359. mla: Barton, Nicholas H. “The Dynamics of Hybrid Zones.” Heredity, vol. 43, no. 3, Springer Nature, 1979, pp. 341–59, doi:10.1038/hdy.1979.87. short: N.H. Barton, Heredity 43 (1979) 341–359. date_created: 2018-12-11T12:08:19Z date_published: 1979-12-01T00:00:00Z date_updated: 2021-12-15T09:29:59Z day: '01' doi: 10.1038/hdy.1979.87 extern: '1' intvolume: ' 43' issue: '3' language: - iso: eng main_file_link: - open_access: '1' url: https://www.nature.com/articles/hdy197987 month: '12' oa: 1 oa_version: Published Version page: 341 - 359 publication: Heredity publication_identifier: eissn: - 1365-2540 issn: - 0018-067X publication_status: published publisher: Springer Nature publist_id: '1696' quality_controlled: '1' status: public title: The dynamics of hybrid zones type: journal_article user_id: 8b945eb4-e2f2-11eb-945a-df72226e66a9 volume: 43 year: '1979' ... --- _id: '4337' article_processing_charge: No author: - first_name: Nicholas H full_name: Barton, Nicholas H id: 4880FE40-F248-11E8-B48F-1D18A9856A87 last_name: Barton orcid: 0000-0002-8548-5240 citation: ama: Barton NH. A hybrid zone in the alpine grasshopper Podisma pedestris. 1979. apa: Barton, N. H. (1979). A hybrid zone in the alpine grasshopper Podisma pedestris. University of East Anglia. chicago: Barton, Nicholas H. “A Hybrid Zone in the Alpine Grasshopper Podisma Pedestris.” University of East Anglia, 1979. ieee: N. H. Barton, “A hybrid zone in the alpine grasshopper Podisma pedestris,” University of East Anglia, 1979. ista: Barton NH. 1979. A hybrid zone in the alpine grasshopper Podisma pedestris. University of East Anglia. mla: Barton, Nicholas H. A Hybrid Zone in the Alpine Grasshopper Podisma Pedestris. University of East Anglia, 1979. short: N.H. Barton, A Hybrid Zone in the Alpine Grasshopper Podisma Pedestris, University of East Anglia, 1979. date_created: 2018-12-11T12:08:20Z date_published: 1979-01-01T00:00:00Z date_updated: 2021-12-16T08:04:16Z day: '01' degree_awarded: PhD extern: '1' language: - iso: eng month: '01' oa_version: None publication_status: published publisher: University of East Anglia publist_id: '1694' status: public title: A hybrid zone in the alpine grasshopper Podisma pedestris type: dissertation user_id: 8b945eb4-e2f2-11eb-945a-df72226e66a9 year: '1979' ...