Site-specific genetic divergence in parallel hybrid zones suggests non-allopatric evolution of reproductive barriers
(2006) In Molecular Ecology 15(13). p.4021-4031- Abstract
- The evolution of reproductive isolation in the presence of gene flow is supported by theoretical models but rarely by data. Empirical support might be gained from studies of parallel hybrid zones between interbreeding taxa. We analysed gene flow over two hybrid zones separating ecotypes of Littorina saxatilis to test the expectation that neutral genetic markers
will show site-specific differences if barriers have evolved in situ. Distinct ecotypes found in contrasting shore habitats are separated by divergent selection and poor dispersal, but hybrid zones appear between them. Swedish islands formed by postglacial uplift 5000 years ago provide opportunities to assess genetic structure in a recently evolved system. Each island... (More) - The evolution of reproductive isolation in the presence of gene flow is supported by theoretical models but rarely by data. Empirical support might be gained from studies of parallel hybrid zones between interbreeding taxa. We analysed gene flow over two hybrid zones separating ecotypes of Littorina saxatilis to test the expectation that neutral genetic markers
will show site-specific differences if barriers have evolved in situ. Distinct ecotypes found in contrasting shore habitats are separated by divergent selection and poor dispersal, but hybrid zones appear between them. Swedish islands formed by postglacial uplift 5000 years ago provide opportunities to assess genetic structure in a recently evolved system. Each island houses a discrete population containing subpopulations of different ecotypes. Hybrid zones between ecotypes may be a product of ecological divergence occurring on each island or a consequence of secondary overlap of ecotypes of allopatric origin that have spread among the islands. We used six microsatellite loci to assess gene flow and
genetic profiles of hybrid zones on two islands. We found reduced gene flow over both hybrid zones, indicating the presence of local reproductive barriers between ecotypes. Nevertheless, subpopulations of different ecotypes from the same island were genetically more similar to each other than were subpopulations of the same ecotype from different islands. Moreover, neutral genetic traits separating the two ecotypes across hybrid zones were site-specific. This supports a scenario of in situ origin of ecotypes by ecological divergence and nonallopatric evolution of reproductive barriers. (Less)
Please use this url to cite or link to this publication:
https://lup.lub.lu.se/record/1982090
- author
- Panova, Marina ; Hollander, Johan LU and Johannesson, Kerstin
- publishing date
- 2006
- type
- Contribution to journal
- publication status
- published
- subject
- keywords
- assortative mating, ecological speciation, Littorina saxatilis, microsatellites, morphometrics, parallel speciation
- in
- Molecular Ecology
- volume
- 15
- issue
- 13
- pages
- 4021 - 4031
- publisher
- Wiley-Blackwell
- external identifiers
-
- scopus:33750217612
- ISSN
- 0962-1083
- DOI
- 10.1111/j.1365-294X.2006.03067.x
- language
- English
- LU publication?
- no
- id
- 1638e91e-a5f2-48bd-bcf7-4959df224434 (old id 1982090)
- date added to LUP
- 2016-04-01 12:15:47
- date last changed
- 2022-03-28 22:29:42
@article{1638e91e-a5f2-48bd-bcf7-4959df224434, abstract = {{The evolution of reproductive isolation in the presence of gene flow is supported by theoretical models but rarely by data. Empirical support might be gained from studies of parallel hybrid zones between interbreeding taxa. We analysed gene flow over two hybrid zones separating ecotypes of Littorina saxatilis to test the expectation that neutral genetic markers<br/><br> will show site-specific differences if barriers have evolved in situ. Distinct ecotypes found in contrasting shore habitats are separated by divergent selection and poor dispersal, but hybrid zones appear between them. Swedish islands formed by postglacial uplift 5000 years ago provide opportunities to assess genetic structure in a recently evolved system. Each island houses a discrete population containing subpopulations of different ecotypes. Hybrid zones between ecotypes may be a product of ecological divergence occurring on each island or a consequence of secondary overlap of ecotypes of allopatric origin that have spread among the islands. We used six microsatellite loci to assess gene flow and<br/><br> genetic profiles of hybrid zones on two islands. We found reduced gene flow over both hybrid zones, indicating the presence of local reproductive barriers between ecotypes. Nevertheless, subpopulations of different ecotypes from the same island were genetically more similar to each other than were subpopulations of the same ecotype from different islands. Moreover, neutral genetic traits separating the two ecotypes across hybrid zones were site-specific. This supports a scenario of in situ origin of ecotypes by ecological divergence and nonallopatric evolution of reproductive barriers.}}, author = {{Panova, Marina and Hollander, Johan and Johannesson, Kerstin}}, issn = {{0962-1083}}, keywords = {{assortative mating; ecological speciation; Littorina saxatilis; microsatellites; morphometrics; parallel speciation}}, language = {{eng}}, number = {{13}}, pages = {{4021--4031}}, publisher = {{Wiley-Blackwell}}, series = {{Molecular Ecology}}, title = {{Site-specific genetic divergence in parallel hybrid zones suggests non-allopatric evolution of reproductive barriers}}, url = {{http://dx.doi.org/10.1111/j.1365-294X.2006.03067.x}}, doi = {{10.1111/j.1365-294X.2006.03067.x}}, volume = {{15}}, year = {{2006}}, }