sh.sePublications
Change search
ReferencesLink to record
Permanent link

Direct link
Fine scale genetic structure in Thresspine sticklback (Gasterosteus aculeatus) along Sweden's coast
Södertörn University, School of Natural Sciences, Technology and Environmental Studies, Biology. Stockholms universitet.
Mälardalens högskola.
Södertörn University, School of Natural Sciences, Technology and Environmental Studies, Biology.ORCID iD: 0000-0003-3389-4162
(English)Manuscript (preprint) (Other academic)
Abstract [en]

There are three basic types of population structures in marine environments; populations that are distinct, with a continuous change and without any differentiation. In each type the population units are characterized by groups of individuals with panmixia within groups and site fidelity to a limited geographic area. Earlier studies of the population genetic structure on sticklebacks in the Baltic Sea have shown none or only little structure. We have sampled 8 sites (253 individuals) along Sweden’s coast to estimate the genetic structure, using five microsatellites and 173 Amplified Fragment Length Polymorphism (AFLP) markers and detected a fine scale genetic structure (AFLP FST= 25%, microsatellites FST = 2.7%). With AFLPs the observed variation followed isolation by distance model (but not with microsatellites). Even sites separated by only 2 km of water are significantly separated. Both Bayesian clustering analysis and Capscale separated populations and identified populations from Gulf of Bothnia (4 psu) and from the west coast (20 psu) as genetically distinctly different from Baltic populations (about 7-8 psu).  In conclusion, gene flow is limited between sampled sites, and since no geographic barriers can be distinguished the population structure is likely caused by the sticklebacks’ behavior. Hence, we have probably sampled either stationary populations of marine sticklebacks, or homing sticklebacks. In this study AFLP and microsatellites did not give congruent results; with AFLPs we got high separation, and genetic variation followed isolation by distance model and supported the continuous change type of population structure.

National Category
Evolutionary Biology Genetics
Identifiers
URN: urn:nbn:se:sh:diva-18916OAI: oai:DiVA.org:sh-18916DiVA: diva2:622590
Note

Som manuskript i avhandling. As manuscript in dissertation.

Available from: 2013-04-26 Created: 2013-05-22 Last updated: 2014-11-12Bibliographically approved
In thesis
1. Genetic response to pollution in sticklebacks; natural selection in the wild
Open this publication in new window or tab >>Genetic response to pollution in sticklebacks; natural selection in the wild
2013 (English)Doctoral thesis, comprehensive summary (Other academic)
Abstract [en]

The last century, humans have been altering almost all natural environments at an accelerating rate, including the Baltic Sea that has highly eutrophicated areas and many coastal industries such as Pulp-mills. For animals living in a habitat that changes there are basically two alternatives, either to cope with the change or become locally extinct. This thesis aims to investigate if recent anthropogenic disturbance in the Baltic Sea can affect natural populations on a genetic level through natural selection.

First, we found a fine-scale genetic structure in three-spine sticklebacks (Gasterosteus aculeatus) populations along the Swedish coast (paper I), indicating limited gene-flow between populations in geographic proximity. Different genetic markers, specifically Amplified Fragment Lenght Polymorpism (AFLP, and microsatellites,  gave different results, highlighting the heterogeneous character of genomes which demonstrates that it is important to choose a genetic marker that is relevant for the question at hand. With a population genomic approach, and a multilocus genetic marker (AFLP), we detected convergent evolution in genotype composition in stickleback populations living in environments affected by pulp-mill effluent (paper II) and in highly eutrophicated environments (paper III), compared to adjacent reference populations. We found loci, in both studies (paper II, III), that were different from a neutral distribution and thus probably under divergent selection for the habitat differences investigated. The selective effect from pulp-mill effluents were more pronounced, but the two different habitats had mutual characters (AFLP loci). In paper IV, we converted five anonymous AFLP loci to sequenced markers and aligned them to the stickleback genome. Four out of five loci aligned within, or close to, coding regions on chromosome I, chromosome VIII, chromosome XIX and chromosome XX. One of the loci, located on chromosome VIII and identified as under divergent selection in both paper II and III, has been identified in other studies as to be under selection for fresh water adaptation, including Baltic Sea stickleback populations.

In conclusion, anthropogenic alterations of natural environments can have evolutionary consequences, probably adaptive, for the animals living there and the evolutionary response exhibited by natural populations can be very fast.

Place, publisher, year, edition, pages
Stockholm: Department of Zoology, Stockholm University, 2013. 41 p.
Series
Södertörn doctoral dissertations, ISSN 1652-7399 ; 79
Keyword
Population genomics, genome scan, divergent selection, Gasterosteus aculeatus, Baltic Sea, pollution
National Category
Evolutionary Biology Genetics Environmental Sciences
Identifiers
urn:nbn:se:sh:diva-18919 (URN)978-91-7447-702-3 (ISBN)978-91-86069-67-4 (ISBN)
Public defence
2013-06-14, Ahlmansalen, Geovetenskapens hus, Svante Arrhenius väg 12, 10:00 (English)
Opponent
Supervisors
Note

At the time of the doctoral defense, the following papers were unpublished and had a status as follows: Paper 1: Manuscript. Paper 3: Manuscript. Paper 4: Manuscript.

Available from: 2013-05-22 Created: 2013-05-22 Last updated: 2014-01-31Bibliographically approved

Open Access in DiVA

No full text

Search in DiVA

By author/editor
Lind, EmmaGrahn, Mats
By organisation
Biology
Evolutionary BiologyGenetics

Search outside of DiVA

GoogleGoogle Scholar

Total: 95 hits
ReferencesLink to record
Permanent link

Direct link