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Patterns of morphological, genetic and epigenetic variation (DNA methylation pattern) were investigated in metallicolous (M) and non-metallicolous (NM) populations of Armeria maritima. A morphological study was carried out using plants from six natural populations grown in a greenhouse. Morphological variation was assessed using seven traits. On the basis of this study, three representative populations were selected for molecular analyses using metAFLP to study sequence- and methylation-based DNA variation. Only one morphological trait (length of outer involucral bracts) was common to both metallicolous populations studied; however, the level of variation was sufficient to differentiate between M and NM populations. Molecular analyses showed the existence of naturally occurring epigenetic variation in A. maritima populations, as well as structuring into distinct between and within population components. We show that patterns of population genetic structure differed depending on the information used in the study. Analysis of sequence-based information data demonstrates the presence of three well-defined and genetically differentiated populations. Methylation-based data show that two major groups of individuals are present, corresponding to the division into M and NM populations. These results were confirmed using different analytical approaches, which suggest that the DNA methylation pattern is similar in both M populations. We hypothesise that epigenetic processes may be involved in microevolution leading to development of M populations in A. maritima.

We compute the low energy threshold corrections to neutrino masses and mixing in the Standard Model (SM) and its minimal supersymmetric version, using the effective theory technique. We demonstrate that they stabilize the renormalization group (RG) running with respect to the choice of the scale to which the RG equation is integrated. (This confirms the correctness of the recent re-derivation of the RGE for the SM in hep-ph/0108005.) The explicit formulae for the low energy threshold corrections corrections can be applied to specific models of neutrino masses and mixing.

We present a comprehensive list of non-native vascular plant species known from the Arctic, explore their characteristics, analyze the extent of naturalization and invasion among investigated regions, and examine pathways of non-native plant introductions. The presence of 341 non-native species in the Arctic was confirmed, of which 188 are naturalized in at least one of 23 regions, while 11 taxa are invasive in three regions. In several Arctic regions there are no naturalized non-native species recorded, whereas in the majority of Arctic regions the number of naturalized species is low. Biogeographic analyses of the non-native vascular plant flora identified three main clusters within the Arctic: American, Asiatic and European. Among all pathways, seed contamination and transport by vehicles have contributed the most to non-native plant introduction to the Arctic.

This review provides a synopsis of the main findings of individual papers in the special issue Terrestrial Biodiversity in a Rapidly Changing Arctic. The special issue was developed to inform the State of the Arctic Terrestrial Biodiversity Report developed by the Circumpolar Biodiversity Monitoring Program (CBMP) of the Conservation of Arctic Flora and Fauna (CAFF), Arctic Council working group. Salient points about the status and trends of Arctic biodiversity and biodiversity monitoring are organized by taxonomic groups: (1) vegetation, (2) invertebrates, (3) mammals, and (4) birds. This is followed by a discussion about commonalities across the collection of papers, for example, that heterogeneity was a predominant pattern of change particularly when assessing global trends for Arctic terrestrial biodiversity. Finally, the need for a comprehensive, integrated, ecosystem-based monitoring program, coupled with targeted research projects deciphering causal patterns, is discussed.