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Southern European columbines (genus Aquilegia) are involved in active processes of diversification, and the Iberian Peninsula offers a privileged observatory to witness the process. Studies on Iberian columbines have provided significant advances on species diversification, but we still lack a complete perspective of the genetic diversification in the Iberian scenario. This work explores how genetic diversity of the genus Aquilegia is geographically structured across the Iberian Peninsula. We used Bayesian clustering methods, principal coordinates analyses, and NJ phenograms to assess the genetic relationships among 285 individuals from 62 locations and detect the main lineages. Genetic diversity of Iberian columbines consists of five geographically structured lineages, corresponding to different Iberian taxa. Differentiation among lineages shows particularly complex admixture patterns at Northeast and highly homogeneous toward Northwest and Southeast. This geographic genetic structure suggests the existence of incomplete lineage sorting and interspecific hybridization as could be expected in recent processes of diversification under the influence of quaternary postglacial migrations. This scenario is consistent with what is proposed by the most recent studies on European and Iberian columbines, which point to geographic isolation and divergent selection by habitat specialization as the main diversification drivers of the Iberian Aquilegia complex.

© 2014 Gesellschaft für Ökologie. Little is currently known about the dynamics of mutualistic interactions in relation to land abandonment. Using data from two studies on frugivory and seed dispersal by carnivorous mammals carried out at the same site, and spanning three decades, we show how plant-frugivore interactions change in the long-term after a process of land abandonment in a mountainous area of NW Spain. Over time, the change in the identities of interacting species was small. However, considering the quantitative participation of each species along with the identity and number of strong links, the change was significant. After land abandonment, two successional plant species (rowan and bramble) and a cultivated species (cherry tree) dominated the interactions with carnivores and red foxes replaced pine martens as the main frugivores. The prevalence of cherry tree increased significantly in this sub-web, probably as a consequence of the preference of carnivores for human-selected fruits (higher pulp/seed ratio) and the abandonment of harvesting as a result of the declining human population. Our results suggest that the frequency of interactions between plants and carnivores may be modulated by plant abundance, which in turn is primarily influenced by land abandonment in this scenario, fruit preference by dispersers and the interaction between these two factors. The temporal assessment of plant-animal mutualisms appears to be a valuable tool to predict the course of successional processes. A functional consequence of red foxes as the main frugivore is a higher frequency of long-distance seed dispersal events, which increases connectivity among plant populations, favors colonization and ultimately may shape the course of the successional process. Our study exemplifies the pressing need for more information on the temporal dynamics of ecological interactions in order to understand how they respond to anthropogenic changes such as land abandonment.

his study explores the possible causes of variation in female reproductive success of the subspecific taxon Primula elatior subsp. bergidensis, a distylic endemic to the north-western Iberian Peninsula, by analysing both vegetative and reproductive traits. In three populations, we marked vegetative and reproductive individuals either by mapping the spatial position of every individual (in one population), or by establishing permanent quadrats (in the remainder two populations). We recorded floral morph (pin or thrum), width and length of the largest leaf, scape length, and number of flowers produced; all individuals were monitored to estimate the number of fruits and seeds produced. The results show that the morph ratio did not differ significantly from 1:1 in any of the populations. The number of flowers per plant varied between populations, and longer scape length was associated with higher fruit set in all populations. Plant size, scape length, and population spatial structure all had major effects on reproductive success, but the strength—and in some cases the direction—of the effects varied among populations.

We studied the variation on floral traits of Narcissus cyclamineus, a species endemic to the northwestern Iberian Peninsula. We analyzed the effect of different breeding systems and the degree of herkogamy and stigmatic exertion on female reproductive success. Results showed that, while variation on floral structures is relatively low (i.e. less than 25% for all sterile structures), CVs for herkogamy and stigmatic exertion are much higher. We also found a considerable variation among populations in the relative position of stigmas and anthers and a significant effect of breeding system (facilitated autogamy, spontaneous autogamy or xenogamy) on fruit set and seed production. The number of seeds per fruit bears no relation with corona size, degree of stigmatic exertion or herkogamy. However, herkogamy showed a marginally significant effect on mean seed weight per fruit. The results highlight the need to analyze the influence of continuous variations in the position of floral organs on the reproductive success of the monomorphic species of the genus Narcissus. © 2009 Springer-Verlag.

To analyze the extent to which early flowering of specialized myrmecochorous plants (i.e. plants producing elaiosome-bearing seeds) may be the result of adaptation for ant dispersal, we investigated flowering and fruiting patterns of common herb and shrub-layer species in a beechwood forest at the western end of the Cantabrian Range (Spain). Over the same period, we estimated ant abundance, the availability of alternative foods for ants, and the rate of removal of seeds by ants. Our results indicate: (i) that the flowering peaks of most strict myrmecochores occurred approximately 4 weeks earlier than in nonmyrmecochores; (ii) that the fruiting peak of both groups of plants occurred around the same time, in early July; (iii) that the peak in ant abundance coincides with the seed availability peak, and precedes the peak in availability of alternative ant foods; and (iv) that the probability of seed removal by Formica rufibarbis (the only ant species present in the study area) varies over the season, peaking in early July. In conclusion, our results show that despite differences in seed size, plants with ant-dispersed seeds show highly synchronous flowering, suggesting that strict myrmecochores in our study area may have adapted their phenologies to the seasonal availability of dispersers.

We examine the hierarchical geographic structure of the interaction between a plant, Helleborus foetidus, and its floral herbivores and pollinators (interactors). Six populations from three distant regions of the Iberian Peninsula were used to examine intra- and inter-regional variation in plant traits, interactors and plant fecundity, and to compare, through selection gradient and path analyses, which traits were under selection, and which interactors were responsible for differential selection. Geographic and temporal congruency in interactor- mediated selection was further tested using a recent analytical approach based on multi-group comparison in Structural Equation Models. Most plant traits, interactors and fecundity differed among regions but not between populations. Similarly, the identity of the traits under selection, the selection gradients (strength and/or the direction of the selection) and the path coefficients (identifying the ecological basis for selection) varied inter- but not intra- regionally. Results show a selection mosaic at the broad scale and, for some traits, a link of differential selection to trait differentiation

• Background and Aims This study examined the effect of plant traits and environmental factors on pollinator visitation in the winter-flowering Helleborus foetidus (Ranunculaceae) in three distant regions in the Iberian Peninsula. • Methods Geographical variation in floral visitor assemblage, plant traits and environmental factors were analysed during the flowering season. • Key Results Differences were found in all plant traits measured (number of open flowers, flower size, number of stamens per flower, and number of nectaries) both within and among regions, and differences among regions in all the environmental factors considered (air temperature, exposure to sunlight, canopy cover, and distance to the nearest neighbour). Differences were also found among regions in the probability that plants would be visited by pollinators. • Conclusions The results show that, although floral display (i.e. number of open flowers on a plant on a given day) consistently explained among-plant differences in visitation rate in all regions, visitation rate was not significantly affected by any other biological or environmental variable. In Helleborus foetidus, then, ‘how’ the plant is would seem to be more important than ‘where’ is it.