Genetic traces of hybrid zone movement across a fragmented habitat
(2022) In Journal of evolutionary biology 35(3). p.400-412- Abstract
Theoretical and empirical studies suggest that the structure and position of hybrid zones can change over time. Evidence for moving hybrid zones has been directly inferred by repeated sampling over time, or indirectly through the detection of genetic footprints left by the receding species and the resulting asymmetric patterns of introgression across markers. We here investigate a hybrid zone formed by two subspecies of the Iberian golden-striped salamander, Chioglossa lusitanica, using a panel of 35 nuclear loci (31 SNPs and 4 allozymes) and one mitochondrial locus in a transect in central Portugal. We found concordant and coincident clines for most of the nuclear loci (n = 22, 63%), defining a narrow hybrid zone of ca. 6 km wide, with... (More)
Theoretical and empirical studies suggest that the structure and position of hybrid zones can change over time. Evidence for moving hybrid zones has been directly inferred by repeated sampling over time, or indirectly through the detection of genetic footprints left by the receding species and the resulting asymmetric patterns of introgression across markers. We here investigate a hybrid zone formed by two subspecies of the Iberian golden-striped salamander, Chioglossa lusitanica, using a panel of 35 nuclear loci (31 SNPs and 4 allozymes) and one mitochondrial locus in a transect in central Portugal. We found concordant and coincident clines for most of the nuclear loci (n = 22, 63%), defining a narrow hybrid zone of ca. 6 km wide, with the centre positioned ca. 15 km south of the Mondego River. Asymmetric introgression was observed at another 14 loci. Their clines are displaced towards the north, with positions located either close to the Mondego River (n = 6) or further northwards (n = 8). We interpret these profiles as genetic traces of the southward displacement of C. lusitanica lusitanica by C. l. longipes over the wider Mondego River valley. We noted the absence of significant linkage disequilibrium, and we inferred low levels of effective selection per locus against hybrids, suggesting that introgression in the area of species replacement occurred under a neutral diffusion process. A species distribution model suggests that the C. lusitanica hybrid zone coincides with a narrow corridor of fragmented habitat. From the position of the displaced clines, we infer that patches of locally suitable habitat trapped some genetic variants that became disassociated from the southward moving hybrid zone. This study highlights the influence of habitat availability on hybrid zone movement.
(Less)
- author
- Sequeira, Fernando ; Arntzen, Jan W ; van Gulik, Davy ; Hajema, Steven ; Diaz, Ruben Lopez ; Wagt, Mattijn and van Riemsdijk, Isolde LU
- publishing date
- 2022-03-01
- type
- Contribution to journal
- publication status
- published
- subject
- keywords
- Animals, DNA, Mitochondrial/genetics, Ecosystem, Hybridization, Genetic, Linkage Disequilibrium, Salamandridae/genetics, Urodela/genetics
- in
- Journal of evolutionary biology
- volume
- 35
- issue
- 3
- pages
- 13 pages
- publisher
- John Wiley & Sons Inc.
- external identifiers
-
- scopus:85124738473
- pmid:35043504
- ISSN
- 1420-9101
- DOI
- 10.1111/jeb.13982
- language
- English
- LU publication?
- no
- additional info
- © 2022 European Society for Evolutionary Biology.
- id
- bd68ff18-59cd-4598-bed9-4e02c04cb5c9
- date added to LUP
- 2023-05-01 08:59:27
- date last changed
- 2024-04-19 21:12:22
@article{bd68ff18-59cd-4598-bed9-4e02c04cb5c9,
abstract = {{<p>Theoretical and empirical studies suggest that the structure and position of hybrid zones can change over time. Evidence for moving hybrid zones has been directly inferred by repeated sampling over time, or indirectly through the detection of genetic footprints left by the receding species and the resulting asymmetric patterns of introgression across markers. We here investigate a hybrid zone formed by two subspecies of the Iberian golden-striped salamander, Chioglossa lusitanica, using a panel of 35 nuclear loci (31 SNPs and 4 allozymes) and one mitochondrial locus in a transect in central Portugal. We found concordant and coincident clines for most of the nuclear loci (n = 22, 63%), defining a narrow hybrid zone of ca. 6 km wide, with the centre positioned ca. 15 km south of the Mondego River. Asymmetric introgression was observed at another 14 loci. Their clines are displaced towards the north, with positions located either close to the Mondego River (n = 6) or further northwards (n = 8). We interpret these profiles as genetic traces of the southward displacement of C. lusitanica lusitanica by C. l. longipes over the wider Mondego River valley. We noted the absence of significant linkage disequilibrium, and we inferred low levels of effective selection per locus against hybrids, suggesting that introgression in the area of species replacement occurred under a neutral diffusion process. A species distribution model suggests that the C. lusitanica hybrid zone coincides with a narrow corridor of fragmented habitat. From the position of the displaced clines, we infer that patches of locally suitable habitat trapped some genetic variants that became disassociated from the southward moving hybrid zone. This study highlights the influence of habitat availability on hybrid zone movement.</p>}},
author = {{Sequeira, Fernando and Arntzen, Jan W and van Gulik, Davy and Hajema, Steven and Diaz, Ruben Lopez and Wagt, Mattijn and van Riemsdijk, Isolde}},
issn = {{1420-9101}},
keywords = {{Animals; DNA, Mitochondrial/genetics; Ecosystem; Hybridization, Genetic; Linkage Disequilibrium; Salamandridae/genetics; Urodela/genetics}},
language = {{eng}},
month = {{03}},
number = {{3}},
pages = {{400--412}},
publisher = {{John Wiley & Sons Inc.}},
series = {{Journal of evolutionary biology}},
title = {{Genetic traces of hybrid zone movement across a fragmented habitat}},
url = {{http://dx.doi.org/10.1111/jeb.13982}},
doi = {{10.1111/jeb.13982}},
volume = {{35}},
year = {{2022}},
}