title: Microsatellite markers show decreasing diversity but unchanged level of clonality in Dryas octopetala (Rosaceae) with increasing latitude.
abstract: OBJECTIVE
  Average arctic temperatures have increased at almost twice the global average in the past 100 years. Most studies on biodiversity along latitudinal gradients have focused on species richness or genetic diversity at lower latitudes, and only a few studies have inferred genetic diversity within a species along a latitudinal gradient at higher latitudes, even though these areas might be most affected by recent climate changes. Here, intraspecific genetic diversity of the arctic-alpine Dryas octopetala (Rosaceae) is studied along a latitudinal gradient to test the hypotheses that genetic diversity decreases and vegetative clonal growth increases with latitude. •
  
  
  METHODS
  Ten microsatellite markers have been developed for D. octopetala and analyzed with population genetic methods in five populations along a latitudinal transect spanning from 59.0°N to 79.9°N. •
  
  
  RESULTS
  The nine microsatellites that were used in the final analyses resulted in a resolution high enough to distinguish between ramets while providing useful information at a larger geographical scale. Three genetic clusters were indicated, a southern Norway group, a northern Norway group, and a Svalbard group, with corresponding decreasing genetic diversity. No trend was found with regard to clonality along the gradient. •
  
  
  CONCLUSIONS
  The newly developed microsatellite markers provide a useful tool for further genetic studies of D. octopetala and its close relatives, addressing population structure as well as phylogeographic patterns. The results of this study support the hypothesis of decreasing genetic diversity with increasing latitude, which may have implications for future adaptability to climate change.
authors.affiliation: Centre for Ecological and Evolutionary Synthesis, Department of Biology, University of Oslo, P.O. Box 1066 Blindern, NO-0316 Oslo, Norway.
authors.forename: Unni
authors.initials: U
authors.lastname: Vik
authors.forename: Marte H
authors.initials: MH
authors.lastname: Jørgensen
authors.forename: Håvard
authors.initials: H
authors.lastname: Kauserud
authors.forename: Inger
authors.initials: I
authors.lastname: Nordal
authors.forename: Anne K
authors.initials: AK
authors.lastname: Brysting