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Summary: Scots pine is the foundation species of diverse forested ecosystems across Eurasia and displays remarkable ecological breadth, occurring in environments ranging from temperate rainforests to arid tundra margins. Such expansive distributions can be favored by various demographic and adaptive processes and the interactions between them.To understand the impact of neutral and selective forces on genetic structure in Scots pine, we conducted range‐wide population genetic analyses on 2321 trees from 202 populations using genotyping‐by‐sequencing, reconstructed the recent demography of the species and examined signals of genetic adaptation.We found a high and uniform genetic diversity across the entire range (global FST 0.048), no increased genetic load in expanding populations and minor impact of the last glacial maximum on historical population sizes. Genetic‐environmental associations identified only a handful of single‐nucleotide polymorphisms significantly linked to environmental gradients.The results suggest that extensive gene flow is predominantly responsible for the observed genetic patterns in Scots pine. The apparent missing signal of genetic adaptation is likely attributed to the intricate genetic architecture controlling adaptation to multi‐dimensional environments. The panmixia metapopulation of Scots pine offers a good study system for further exploration into how genetic adaptation and plasticity evolve under gene flow and changing environment. See also the Commentary on this article by Duffy, 243: 830–832. [ABSTRACT FROM AUTHOR]

Broad-scale plastid (chloroplast) DNA studies of beech ( Fagus sylvatica) populations suggest the existence of glacial refugia and introgression zones in south-eastern Europe. We choose a possible refugium of beech in northern Greece, Mt. Paggeo, which hosts a private plastid haplotype for beech, to conduct a fine-scale genetic study. We attempt to confirm or reject the hypothesis of the existence of a small-scale refugium and to gain an understanding of the ecological and topographical factors affecting the spatial distribution of plastid haplotypes in the area. Our results reveal a high haplotype diversity on Mt. Paggeo, but the overall distribution of haplotypes shows no significant correlation with the ecological characteristics of the beech forests. However, the private haplotype is found at high frequencies in beech forests located in or near ravines, having a high spatial overlap with a relict vegetation type occurring in ecological conditions found mainly in ravines. This result emphasizes the importance of topography in the existence of glacial refugia in the wider area. Furthermore, haplotypes originating from two more widespread beech lineages in Greece are found on Mt. Paggeo, indicating a possible mixing of populations originating from a local refugium with populations from remote refugia that possibly migrated into the area after the last glaciation. © 2014 The Linnean Society of London, Botanical Journal of the Linnean Society, 2014, 174, 516-528. [ABSTRACT FROM AUTHOR]