DOI: 10.5061/dryad.ht76hdrjp
title: Genetic diversity and differentiation of populations of Anthyllis vulneraria along elevational and latitudinal gradients

description: The abundant centre model (ACM) predicts that the suitability of
 environmental conditions for a species decreases from the centre of its
 distribution towards its range periphery and consequently its populations
 will become scarcer, smaller and more isolated, resulting in lower genetic
 diversity and increased differentiation. However, little is known about
 whether genetic diversity shows similar patterns along elevational and
 latitudinal gradients with similar changes in important environmental
 conditions. Using microsatellite markers we studied the genetic diversity
 and structure of 20 populations each of Anthyllis vulneraria along
 elevational gradients in the Alps from the valleys to the elevational
 limit (2500 m), and along a latitudinal gradient (2500 km) from Central
 Europe to the range margin in northern Scandinavia. Both types of
 gradients corresponded to a 11.5 °C difference in mean annual temperature.
 Genetic diversity strongly declined and differentiation increased with
 latitude in line with the predictions of the ACM. However, as population
 size did not decline with latitude and genetic diversity was not related
 to population size in A. vulneraria, this pattern is not likely to be due
 to less favourable conditions in the North, but due to serial founder
 effects during the post-glacial recolonization process. Genetic diversity
 was not related to elevation, but we found significant isolation by
 distance along both gradients, although the elevational gradient was
 shorter by orders of magnitude. Subarctic populations differed genetically
 from alpine populations indicating that the northern populations did not
 originate from high elevational Alpine ones. Our results support the
 notion that postglacial latitudinal colonization over large distances
 resulted in a larger loss of genetic diversity than elevational range
 shifts. The lack of genetic diversity in subarctic populations may
 threaten their long-term persistence in the face of climate change,
 whereas alpine populations could benefit from gene flow from low-elevation
 populations.
description: <strong>Genotyping using
 microsatellite markers</strong>
 We extracted genomic DNA using
 a DNeasy Plant Mini Kit (QIAGEN, Hilden, Germany) starting from
 approximately 10 mg of dried material. Samples were genotyped at 17 microsatellite
 loci (AV2, AV3, AV7, AV8, AV10, AV12, AV14, AV23, AV-000290, AV-002128,
 AV-004868, AV-005692, AV-015354, AV-020270, AV-021012, AV-021224,
 AV-021803, for references see Van Glabeke et al. 2007 and Kesselring et
 al. 2013) in four multiplex reactions using the QIAGEN Multiplex PCR Kit
 (QIAGEN, Hilden, Germany). Multiplex 1 contained loci AV23 (Van Glabeke et
 al., 2007), AV-000290 and AV-015354 (Kesselring et al., 2013). Multiplex 2
 contained loci AV2, AV3, AV12 (Van Glabeke et al., 2007), AV-021012 and
 AV-021224 (Kesselring et al., 2013). Multiplex 3 contained loci AV7, AV8,
 AV10 (Van Glabeke et al. 2007) and AV-004868 (Kesselring et al., 2013).
 Multiplex 4 contained loci AV14 (Van Glabeke et al., 2007), AV-002128,
 AV-005692, AV-020270 and AV-021803 (Kesselring et al., 2013).
 We amplified each
 multiplex using the QIAGEN multiplex Kit (QIAGEN, Hilden, Germany).  Each
 multiplex reaction contained 1 x QIAGEN multiplex master mix and 0.2 μM of
 each primer in a total volume of 6 μl.
 The PCR conditions were: 5’ at
 95 °C, 30 cycles of 30’’ at 95 °C, 90’’ at 53 °C (55 °C for Multiplex 1)
 and 30’’ at 72 °C and a last step of 30’ at 68 °C. Reactions were
 performed using a Mastercycler nexus (Eppendorf, Hamburg, Germany). PCR
 products were separated using an automated sequencer (3730xl DNA Analyzer,
 Applied Biosystems). The data were analysed using Geneious 11.1.5 (https
 ://www.geneious.com, Kearse et al., 2012).
 To estimate the error rate, we
 extracted and genotyped 5% of the samples twice. The mean error rate per
 sample was calculated as the number of errors divided by the total number
 of analysed loci within replicated samples. We randomly chose one of the
 repeated samples to continue with the analyses.
description: Spreadsheet programm (e.g. Excel)