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Frugivory in lizards is often assumed to be constrained by body size; only large individuals are considered capable of consuming fruits, with the potential of acting as seed dispersers. However, only one previous study has tested the correlation of frugivory with body and head size at an archipelago scale across closely related species. All nine lava lizards (Microlophusspp.) were studied on the eleven largest Galápagos islands from 2010 to 2016 to investigate whether frugivory is related to body and head size. We also tested whether fruit abundance influences fruit consumption and explored the effect of seed ingestion on seedling emergence time and percentage. Our results showed that across islands, lava lizards varied considerably in size (64-102 mm in mean snout-vent length) and level of frugivory (1-23%, i.e., percentage of droppings with seeds). However, level of frugivory was only weakly affected by size as fruit consumption was also common among small lizards. Lava lizards consumed fruits throughout the year and factors other than fruit abundance may be more important drivers of fruit selection (e.g., fruit size, energy content of pulp). From 2,530 droppings, 1,714 seeds of at least 61 plant species were identified, 76% of the species being native to the Galápagos. Most seeds (91%) showed no external structural damage. Seedling emergence time (44 versus 118 days) and percentage (20% versus 12%) were enhanced for lizard-ingested seeds compared to control (uningested) fruits. De-pulping by lizards (i.e., removal of pulp with potential germination inhibitors) might increase the chances that at least some seeds find suitable recruitment conditions. We concluded that lizards are important seed dispersers throughout the year and across the whole archipelago, regardless of body size.

In recent years, as economic globalization and long-distance trade have increased, so has the unintentional transport of non-human species. During the past 30 years, the species diversity of harvestmen (Opiliones) in northern Europe has changed dramatically due to the arrival of new species from southern Europe. Here we explore the changing harvestmen diversity at two scales: 1) the scale of Europe, where we propose the hypothesis that these new, and in some cases invasive, harvestmen species have expanded northwards, aided by the increased traffic along the European transport network, and 2) the scale of specific sites in Central Jutland, Denmark, where we investigated the dispersion of non-native harvestmen species in a former brown coal mining area, as well as areas in the vicinity. We found that the proportion of harvestmen belonging to non-native species was larger in areas characterized by more car and truck traffic than in areas where human disturbance was less frequent. Thus, we theorize that the increase in vehicular transport and intracontinental trade is the main cause of the initially patchy distributions observed for non-native harvestmen in northern Europe. This study provides an example of how succession of non-native species can be driven by specific cultural landscape changes; thus we argue that this type of succession constitutes an important ethnobiological process.

Removal of invasive exotic shrubs from mountaintop communities increased the number of pollinators and positively altered pollinator behaviour, which enhanced native fruit production, indicating that the degradation of ecosystem functions is partly reversible.

SummaryWorldwide, there is a well-documented crisis for bees and other pollinators which represent a fundamental biotic capital for wild life conservation, ecosystem function, and crop production. Among all pollinators of the world, bees (Hymenoptera: Apoidea) constitute the major group in species number and importance, followed by hover flies (Diptera: Syrphidae). The Aegean constitutes one of the world's hotspots for wild bee and other pollinator diversity including flies (mainly hover flies and bee flies), beetles, and butterflies. Despite this advantage, our present knowledge on Greek pollinators is poor, due to a lack of focused and systematic research, absence of relevant taxonomic keys, and a general lack of taxonomic experts in the country. As a result, assessments of pollinator loss cannot be carried out and the causes for the potential pollinator loss in the country remain unknown. Consequently, the desperately needed National Red Data list for pollinators cannot be compiled. This new research (2012–2015) aims to contribute to the knowledge of the pollinator diversity in Greece, the threats pollinators face, as well as the impacts these threats may have on pollination services. The research is conducted in the Aegean archipelago on > 20 islands and several mainland sites in Greece and Turkey. Prime goals are: i. the assessment of bee and hover fly diversity (species, genetic); ii. their pollination services; and iii. the effects of climate change, grazing, intensive bee-keeping, fires, electromagnetic radiation on bee diversity and ecology, as well as on plant-pollinator networks. At the same time, this research contributes to the taxonomic capital in Greece and the Eastern Mediterranean, focusing on the creation of the first identification keys for pollinators, the training of new scientists, as well as the enrichment and further development of the Melissotheque of the Aegean, a permanent reference collection of insect pollinators established at the University of the Aegean.

Using a sample of 1,403 flowering plant species, we tested the hypothesis that flower openness and flower-visitor generalization level of a plant species correlate positively. The “flower-visitor generalization level” Lnof a flowering plant species n, here defined as number of flower-visiting animal species attracted to the flowers of nin a given study site, varied enormously among plant species. Its frequency distribution was extremely skewed. Within a study site, Lalso increased with number of flower-visitor species A. In order to correct for this, we expressed Lrelatively, as the proportion of the total flower-visitor fauna in a study site that visited a given plant species (relative generalization level, L/A). We listed the top-10 most generalized species (both according to Land L/A) in the “world”, i.e., out of our sample of 1,403 plant species. Flower openness is defined as accessibility to the interior of the flower. We placed the blossom classes of Fægri & van der Pijl along a gradient, albeit not very well defined, of decreasing flower openness (dish-bowl, bell-funnel, head-brush, tube, gullet, flag) and tested for any relationship to their generalization level. The classes differed slightly but significantly in their level of L/A. Tube, bell-funnel, and dish-bowl had the highest generalization level and flag, gullet, and head-brush the lowest. Thus, flower openness and generalization level were not correlated. We discuss other factors influencing generalization level such as accessibility to pollen and nectar, morphology and behavior of visitor, and species diversity of the different functional types of visitors.

AbstractA pollination network of 26 pollinator species interacting with 17 plant species from the small Greenlandic island Uummannaq was analyzed for multiple parameters values. Of the insects collected, 77% of all individuals and 77% of all species belonged to Diptera. The ratio of pollinators to plant species was 1.5, which is lower than in other Arctic pollination networks. This might be a double-island effect as Uummannaq is a small island next to Greenland. Connectance was 14.3%, and linkage level of pollinator and plant species averaged 2.4 and 3.7 species links, respectively. The characteristic path length and average clustering coefficient of the 1-mode networks were 1.4 and 0.83, respectively, for the pollinator species and 1.3 and 0.79, respectively, for the plant species. For both pollinator species and plant species, the tail of the degree distribution had the best fit to an exponential model, indicating that the most connected species was constrained in their linking. However, the extremely short path length and high clustering indicated that the networks had small-world behavior, meaning that any disturbance is spread very fast to the entire network and that the networks are error tolerant but vulnerable to attack on the most linked species.

AbstractEffects of size and isolation of Centaurea scabiosa(Asteraceae) populations on herbivory level in flower heads were examined in eight populations of 2,280-44,441 flower heads, each population being separated by 1 to 8 km from the others. Three common flower head herbivores were observed. Two of these (Cerajocera ceratocera[Diptera: Tephritidae] and Isocoluscf. rogenhoferi[Hymenoptera: Cynipidae]) were specialists, and the third (Eucosma cana[Lepidoptera: Tortricidae]) was a generalist on the subfamily Cynaroiideae to which C. scabiosabelongs. All three species increased their herbivory level with size of host plant population. We compared the explanatory power of three measures of population isolation: 1) the traditional measure of distance to nearest-neighbour population, 2) cumulative proximity of all surrounding populations, and 3) a measure termed biological proximity, combining the effects of distance to other populations and their size. Both 2) and 3) explained surprisingly little of the observed herbivory. Thus population size and distance to nearest-neighbour population were the two best predictors of level of herbivory.

In only a few perennial herbs is age determination of individual plants possible. The life cycle of Corydalis intermediaand C. solidais described. Plants have an age in years identical to the number of dead sheaths outside their underground tuber. Various ways to determine age in other species are reviewed: No. of dead layers around corm: Corydalis cava; no. of dead layers around tuber: Corydalis pumila, Drosera erythrorhiza, D. bulbosa; no. of dead remains of leaves/inflorescence stalks to the side of the corm: Philydrella pygmaea; no. of collaterals in corm: Liatris aspera; no. of nodes on rootstock: Trillium erectum; and no. of bands of high and low density of leaf scars on stems: Aeoniumspecies.

The presence of diverse and species-rich plant lineages on oceanic islands is most often associated with adaptive radiation. Here we discuss the possible adaptive significance of some of the most prominent traits in island plants, including woodiness, monocarpy and sexual dimorphisms. Indirect evidence that such traits have been acquired through convergent evolution on islands comes from molecular phylogenies; however, direct evidence of their selective value rarely is obtained. The importance of hybridization in the evolution of island plants is also considered as part of a more general discussion of the mechanisms governing radiations on islands. Most examples are from the Hawaiian and Canarian floras, and in particular from studies on the morphological, ecological and molecular diversification of the genus Aeonium, the largest plant radiation of the Canarian Islands.

Growth forms of 22 species of Aeonium(Crassulaceae) were quantified. Since all species are simple in their modular construction, models were developed to predict module length, branching mode and flowering probability using linear and logistic regression. When combined, the parameters of these models are species specific. A discriminant analysis generates a statistically significant separation of species at the level of phylogenetic sections. The results therefore demonstrate the phylogenetic value of growth rules in plants. This dynamic approach strongly contrasts with the traditional static view on forms in systematics and morphology. It also leaves scope for predicting the evolutionary pathways of morphological change which have caused the great diversity of growth forms in the genus Aeonium.

Differences in reproductive biology between two orchid species were examined: Eight Danish populations of the nectarless Dactylorhiza majalisssp. majalisand six Swedish populations of the nectar‐producing Gymnadenia conopseassp. densiflora. Population size varied from 24 to 1700 flowering individuals in D. majalisand from 100 to 1200 in G. conopsea. Dactylorhiza majalishad only half as many flowers per spike as G. conopsea. Fruit‐set of D. majalisranged from 16 to 39%, much lower than the fruit‐set of G. conopsea(78–91%). Thus in the species with a few flowers and no nectar a lower fruit‐set was observed than in the species with many flowers and presence of nectar. The low fruit‐set of D. majaliswas pollen‐limited and fruit‐set was positively correlated with pollinia removal and the latter was negatively correlated with population size. In both species, fruit‐set and population size were uncorrelated.

Several studies relate removal of diaspores from different ant-dispersed plant species to the size of their claiosomes. This study is the first one to relate intraspecific variation in claiosome size to removal of diaspores by ants. This approach circumvents the problem posed by interspecific variation in chemistry and morphology of elaiosomes. We used the systemHepatica nobilis Mill. (Ranunculaceae) andMyrmica ruginodis Nyl. The elaiosome was the attractive part of the diaspore and its attractiveness decreased quickly after release from the fruit. In experimental runs where ants collected diaspores, the elaiosome size of accepted diaspores was larger than of those rejected and the largest diaspores were collected first. Since size of diaspore, elaiosome and achene were correlated, the diaspores that were removed first had both the largest elaiosome and achene. However, our experiments suggested that elaiosome size was more important to removal than achene size or the elaiosome:achene size ratio. If ant dispersal improves plant fitness, elaiosome size and hence diaspore size would be expected to increase over time. However, such directional selection mediated by the ants is probably counterbalanced by the plant. Seed predators and a negative trade-off between number and size of seeds would, among other factors, select for smaller diaspore size,i.e. counteract the effect of the ants' preference for larger elaiosomes.

Wasps pollinating the orchids Epipactis purpurataand E. helleborinebecome slow and very “sluggish” when drinking these species' nectar which is known to be toxic. We found that the nectar contains six types of fungi and three types of bacteria which arrive by air or by wasps to the flowers. Some of these micro-organisms may be transferred from ripe fuits of other plants also visited by the wasps. One of the nectar-fungi and one of the bacteria produce ethanol in the presence of sugar. Thus to some extent, Epipactis-visiting wasps themselves make their nectar toxic. On average, a micro-organism type was present in 13% of the nectar samples. The most frequent fungus on both fruit, wasps and nectar was the ethanol-producing Cladosporium. Another nectar-fungus Candidawas not found on wasps and fruits. A ‘white’ bacteria type was common to fruit, wasps and nectar,whereas a ‘yellow’ type only was present in nectar and fuit. Thus, at least Cladosporiumand the ‘white’ bacteria type might often be transported from fruits to nectar by wasps. The importance to the pollination of the orchids of this toxification of their nectar is discussed.

On the Canary Islands, we studied reproductive ecology of the perennial laurel forest herbCedronella canariensis (Lamiaceae). Flowers contained small quantities of concentrated nectar. Flower visitors were mainly bumblebees (Bombus terrestris subsp.canariensis) and lepidopterans (especiallyMacroglossa stellatarum). Their abundance, pollen load, and behaviour are reported.Cedronella canariensis was facultatively autogamous. The P:O ratio was higher than expected for a plant with a breeding system of this nature. Seed set was not pollen-limited. Selfed and outcrossed seeds differed in weight. Small, lightly coloured flowers with dysfunctional stamens appeared towards the end of the season. This male-sterility might be induced by drought.

Pollination ofLaurus azorica (Lauraceae), a dioecious Macaronesian tree, was studied. Male and female trees had the same size distribution. The population had 2.5 times as many male trees as females. In addition, males produced more flowers, and their inflorescences lasted longer. Individual flower lifetime and length of flowering season were the same in both sexes. Between the years of observation, one tree changed sex. Pollinators wereHalictinae bees and the flyTachina canariensis. The bees collected pollen and nectar and the fly collected nectar from both sexes. Both species visited other plants as well. The evolution of breeding systems inLauraceae is discussed.

Jasminum odoratissimum is a Madeira and Canary Islands endemic showing classic heterostyly, i.e. with long‐styled flowers with anthers at a low level in the corolla tube and short‐styled flowers with anthers at a high level in the corolla tube. Short‐styled flowers have large pollen, whereas long‐styled flowers have small pollen. The two types are present in equal frequencies in the population.

In recent years, the analysis of interaction networks has grown popular as a framework to explore ecological processes and the relationships between community structure and its functioning. The field has rapidly grown from its infancy to a vibrant youth, as reflected in the variety and quality of the discussions held at the first international symposium on Ecological Networks in Coimbra—Portugal (23–25 October 2013). The meeting gathered 170 scientists from 22 countries, who presented data from a broad geographical range, and covering all stages of network analyses, from sampling strategies to effective ways of communicating results, presenting new analytical tools, incorporation of temporal and spatial dynamics, new applications and visualization tools.1During the meeting it became evident that while many of the caveats diagnosed in early network studies are successfully being tackled, new challenges arise, attesting to the health of the discipline.