HOME HELP FEEDBACK SUBSCRIPTIONS ARCHIVE SEARCH TABLE OF CONTENTS		QUICK SEARCH:   [advanced] Author: Keyword(s): Year:  Vol:  Page:

This Article Full Text Full Text (PDF) Submit a response Alert me when this article is cited Alert me when eLetters are posted Alert me if a correction is posted Services Email this article to a friend Similar articles in this journal Similar articles in ISI Web of Science Similar articles in PubMed Alert me to new issues of the journal Download to citation manager Citing Articles Citing Articles via HighWire Citing Articles via ISI Web of Science (28) Citing Articles via Google Scholar Google Scholar Articles by Hagen, A. R. Articles by Brochmann, C. Search for Related Content PubMed PubMed Citation Articles by Hagen, A. R. Articles by Brochmann, C. Agricola Articles by Hagen, A. R. Articles by Brochmann, C.

Trans-Atlantic dispersal and phylogeography of Cerastium arcticum (Caryophyllaceae) inferred from RAPD and SCAR markers¹

² Botanical Garden and Museum, University of Oslo, Sarsgate 1, N-0562 Oslo, Norway; and ³ Department of Ecology and Molecular Biology, Section of Genetics and Microbiology, The Royal Veterinary and Agricultural University, Thorvaldsensvej 40, DK-1871 Frederiksberg C, Copenhagen, Denmark

Cerastium arcticum is an autogamous pioneer species with a distribution limited to the North Atlantic region. It has been suggested that such species must have survived in ice-free refugia on both sides of the Atlantic throughout the last, or even several, of the Pleistocene glaciations, because they lack special adaptations for long-distance dispersal. To address the possibility for recent trans-Atlantic dispersal of C. arcticum, we analyzed random amplified polymorphic DNA (RAPD) and sequence characterized amplified region (SCAR) differentiation among 26 populations of this high-polyploid species. Three SCAR markers were obtained that verified the main patterns identified in the RAPD analysis. Eighty-four multilocus RAPD phenotypes were observed in the 126 plants analyzed, based on 35 polymorphic markers. Multivariate analyses and analyses of molecular variance (AMOVAs) identified two highly divergent groups of populations: one arctic group (western and eastern Greenland, and the archipelagos of Svalbard and Franz Josef Land) and one nonarctic group (southern and northern Norway, and Iceland), indicating that C. arcticum is composed of two lineages with different evolutionary histories. However, there was little geographic structuring within each lineage, in spite of the fact that both lineages are disjunctly distributed across the Atlantic. Occurrence of very similar, in some cases even identical RAPD multilocus phenotypes on both sides of the Atlantic in this autogamous allopolyploid is most probably caused by postglacial dispersal. The present geographic distribution of C. arcticum may thus have been established after trans-Atlantic expansion from two Weichselian refugia, one for each evolutionary lineage. Unexpectedly, the level of intrapopulational variation increased towards the north. This may reflect that interpopulational migration is most extensive in the treeless arctic environment, where the species has a more continuous distribution than in the more southerly areas.

Key Words: Cerastium arcticum • long-distance dispersal • phylogeography • RAPD • SCAR

This article has been cited by other articles:

				A.-C. Scheen, C. Brochmann, A. K. Brysting, R. Elven, A. Morris, D. E. Soltis, P. S. Soltis, and V. A. Albert Northern hemisphere biogeography of Cerastium (Caryophyllaceae): insights from phylogenetic analysis of noncoding plastidnucleotide sequences Am. J. Botany, June 1, 2004; 91(6): 943 - 952. [Abstract] [Full Text] [PDF]

				M. Coleman, A. Liston, J. W. Kadereit, and R. J. Abbott Repeat intercontinental dispersal and Pleistocene speciation in disjunct Mediterranean and desert Senecio (Asteraceae) Am. J. Botany, October 1, 2003; 90(10): 1446 - 1454. [Abstract] [Full Text] [PDF]

				R. Holderegger and R. J. Abbott Phylogeography of the Arctic-Alpine Saxifraga oppositifolia (Saxifragaceae) and some related taxa based on cpDNA and ITS sequence variation Am. J. Botany, June 1, 2003; 90(6): 931 - 936. [Abstract] [Full Text] [PDF]

				I. Stehlik Glacial history of the alpine herb Rumex Nivalis (Polygonaceae): a comparison of common phylogeographic methods with nested clade analysis Am. J. Botany, December 1, 2002; 89(12): 2007 - 2016. [Abstract] [Full Text] [PDF]

				A. Tribsch, P. Schonswetter, and T. F. Stuessy Saponaria Pumila (Caryophyllaceae) and the Ice Age in the European Alps Am. J. Botany, December 1, 2002; 89(12): 2024 - 2033. [Abstract] [Full Text] [PDF]

				L.-B. Zhang, H. P. Comes, and J. W. Kadereit Phylogeny and quaternary history of the European montane/alpine endemic Soldanella (Primulaceae) based on ITS and AFLP variation Am. J. Botany, December 1, 2001; 88(12): 2331 - 2345. [Abstract] [Full Text] [PDF]