English   español  
Please use this identifier to cite or link to this item: http://hdl.handle.net/10261/78670
Share/Impact:
Statistics
logo share SHARE logo core CORE   Add this article to your Mendeley library MendeleyBASE

Visualizar otros formatos: MARC | Dublin Core | RDF | ORE | MODS | METS | DIDL
Exportar a otros formatos:

Title

Mixed but not admixed: a spatial analysis of genetic variation of an invasive ascidian on natural and artificial substrates

AuthorsOrdóñez, Víctor; Pascual, Marta; Rius, Marc ; Turon, Xavier
Issue Date2013
PublisherSpringer
CitationMarine Biology 160 :1645-1660 (2013)
AbstractFollowing the introduction to a new area (preborder dispersal), post-border processes determine the success in the establishment of non-indigenous species (NIS). However, little is known on how these post-border processes shape the genetic composition of NIS at regional scales. Here, we analyse genetic variation in introduced populations along impacted coastlines to infer demographic and kinship dynamics at the post-border stage. We used as a model system the ascidian species Microcosmus squamiger that has been introduced worldwide. This species can colonize and grow fast on man-made artificial structures, impacting activities such as mariculture. However, it can also establish itself on natural substrates, thus altering natural communities and becoming an ecological problem. We genotyped 302 individuals from eight populations established on natural and artificial substrates in the north-western Mediterranean Sea, using six microsatellite loci. We then compared the resulting genotypes with those found within the native range of the species. We found high levels of genetic diversity and allelic richness in all populations, with an overall deficit of heterozygotes. Autocorrelation analyses showed that there was no withinpopulation genetic structure (at a scale of tens of metres); likewise, no significant differentiation in pairwise comparisons between populations (tens of kilometres apart) and no isolation-by-distance pattern was found. The results suggest that M. squamiger has a natural capacity for high dispersal from one patch of hard substrate to another and no differences whatsoever could be substantiated between natural and artificial substrates. Interestingly, two groups of genetically differentiated individuals were detected that were associated with the two ancestral source areas of the worldwide expansion of the species. Individual assignment tests showed the coexistence of individuals of these two clusters in all populations but with little interbreeding among them as the frequency of admixed individuals was only 15 %. The mechanism responsible for maintaining these genetic pools unmixed is unknown, but it does not appear to compromise post-border colonization of introduced populations.
Description16 páginas, 4 figuras, 4 tablas.
Publisher version (URL)http://dx.doi.org/10.1007/s00227-013-2217-5
URIhttp://hdl.handle.net/10261/78670
DOI10.1007/s00227-013-2217-5
ISSN0025-3162
Appears in Collections:(CEAB) Artículos
Files in This Item:
File Description SizeFormat 
Ordonez et al Mar Biol preprint.pdf575,06 kBAdobe PDFThumbnail
View/Open
Show full item record
Review this work
 

Related articles:


WARNING: Items in Digital.CSIC are protected by copyright, with all rights reserved, unless otherwise indicated.