We investigated clonal diversity, genet size structure and genet longevity in populations of four arctic-alpine plants (Carex curvula, Dryas octopetala, Salix herbacea and Vaccinium uliginosum) to evaluate their persistence under past climatic oscillations and their potential resistance to future climate change. The size and number of genets were determined by an analysis of amplified fragment length polymorphisms and a standardized sampling design in several European arctic-alpine populations, where these species are dominant in the vegetation. Genet age was estimated by dividing the size by the annual horizontal size increment from in situ growth measurements. Clonal diversity was generally high but differed among species, and the frequency distribution of genet size was strongly left-skewed. The largest C. curvula genet had an estimated minimum age of c. 4100 years and a maximum age of c. 5000 years, although 84.8% of the genets in this species were <200 years old. The oldest genets of D. octopetala, S. herbacea and V. uliginosum were found to be at least 500, 450 and 1400 years old, respectively. These results indicate that individuals in the studied populations have survived pronounced climatic oscillations, including the Little Ice Age and the postindustrial warming. The presence of genets in all size classes and the dominance of presumably young individuals suggest repeated recruitment over time, a precondition for adaptation to changing environmental conditions. Together, persistence and continuous genet turnover may ensure maximum ecosystem resilience. Thus, our results indicate that long-lived clonal plants in arctic-alpine ecosystems can persist, despite considerable climatic change.

The presence of specialized female sperm-storage organs has been recognized as an important factor influencing postcopulatory sexual selection via sperm competition and cryptic female choice in internally fertilizing species. We morphologically examined the complexity of sperm-storage organs in the carrefour (spermatheca and fertilization pouch) in 47 species of stylommatophoran gastropods. We used partial 28S rDNA sequences to construct a molecular phylogeny, and applied maximum likelihood (ML) and Bayesian methods to investigate the history of spermatheca diversification and to test different hypotheses of sperm-storage organ evolution. The phylogenetic reconstruction supported several gains and losses of spermathecae. Moreover, a complex spermatheca was associated with the occurrence of love darts or other kinds of auxiliary copulatory organs, the presence of a long penial flagellum, and cross-fertilization as the predominant mating system. However, our results also suggest associations of carrefour complexity with body size, reproductive strategy (semelparity versus iteroparity), reproductive mode (oviparity versus ovoviviparity), and habitat type. Carrefour length in 17 snail species possessing a spermatheca was positively correlated with sperm length.Our results indicate that postcopulatory sexual selection as well as life history and habitat specificity may have influenced the evolution of female sperm-storage organs in hermaphroditic gastropods.

Bulbil-producing P. alpina, showing a fitness cost at lower elevations compared with seed-producing plants, seem better adapted to higher elevations. By means of its two reproductive modes and the capacity to adjust plastically, P. alpina is able to occupy a broad ecological niche across a large elevational range.

Summary1. Glacial history has affected the phylogeographic structure of numerous Alpine plant species, but its impact on phenotypic differentiation has been little studied. Therefore, we asked whether phenotypic differentiation in a common garden reflects the phylogeographic structure of the widespread Alpine plant Geum reptans L. 2. We combined a molecular investigation with a common garden experiment and investigated genets from 16 populations of G. reptans sampled from the European Alps. Using neutral molecular markers (RAPDs) and Bayesian cluster analysis, we analysed the species' genetic differentiation and phylogeographic structure. In the common garden, we measured the differentiation of phenotypic traits related to growth, reproduction and leaf morphology. 3. Molecular analysis partitioned the populations into three genetic groups, indicating pronounced phylogeographic structure. Regional molecular variation was correlated with regional phenotypic differentiation. 4. Quantitative trait differentiation (Q ST ) differed from neutral molecular differentiation (G ST ) in 10 of 11 traits, indicating that selection has contributed to phenotypic differentiation. Significant negative correlations between biomass and precipitation records for site of origin are a further indication of adaptation. 5. Synthesis. The current study compared regional molecular variation and phenotypic differentiation among populations of a widespread species in the context of extreme range changes during glaciations in the Alps. Because the common garden phenotypic differentiation of G. reptans reflects its phylogeographic structure, we conclude that glacial history affected both genotypes and phenotypes. The results suggest that the present-day phenotypic differentiation was caused by genetic drift and limited gene flow between populations in glacial refugia and during post-glacial recolonization, as well as by adaptation to current climatic conditions. Our findings are relevant for understanding the adaptive potential of Alpine plants and predicting potential range shifts in response to future climate change.

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