The linear response of alginate-phenyl boronic acid (Alg-PBA) esters shows a universal, composition-independent viscoelastic fluid-like behaviour. Reversible association of alginates governs their rheology at all compositions (viz. at all alginate concentrations and solution pH). However, their high strain behaviour is very sensitive to composition. Tuning composition affords liquids that neck to form filaments capable of being drawn to large elongations without failure. We interpret our data by invoking strain-dependent association and dissociation rates for the alginates. High association rates at high strain result in materials with viscoelastic liquid like behaviour.

This Directions piece presents the project ParticiPat: Patrimonio y participación social: propuesta metodológica y revisión crítica (ParticiPat: Heritage and Social Participation: Methodological Proposal and Critical Review). ParticiPat is a multidisciplinary and multisituated research project involving fourteen researchers from different disciplines and institutions that aims to analyze critically the ubiquitous buzzwords and practices of participation¿as well as its key institutions and actors¿affecting heritage management in Spain, Portugal, or Mexico. This article advances preliminary results derived from the authors¿ case study of a natural park and biosphere reserve in Spain. In doing so, it contributes to the anthropological examination of what has recently been described by different authors as the emergence of a new form of governance based on discourses and practices of participation.

A phylogenetic tree at the species level is still far off for highly diverse insect orders, including the Coleoptera, but the taxonomic breadth of public sequence databases is growing. In addition, new types of data may contribute to increasing taxon coverage, such as metagenomic shotgun sequencing for assembly of mitogenomes from bulk specimen samples. The current study explores the application of these techniques for large-scale efforts to build the tree of Coleoptera. We used shotgun data from 17 different ecological and taxonomic datasets (5 unpublished) to assemble a total of 1942 mitogenome contigs of >3000 bp. These sequences were combined into a single dataset together with all mitochondrial data available at GenBank, in addition to nuclear markers widely used in molecular phylogenetics. The resulting matrix of nearly 16,000 species with two or more loci produced trees (RAxML) showing overall congruence with the Linnaean taxonomy at hierarchical levels from suborders to genera. We tested the role of full-length mitogenomes in stabilizing the tree from GenBank data, as mitogenomes might link terminals with non-overlapping gene representation. However, the mitogenome data were only partly useful in this respect, presumably because of the purely automated approach to assembly and gene delimitation, but improvements in future may be possible by using multiple assemblers and manual curation. In conclusion, the combination of data mining and metagenomic sequencing of bulk samples provided the largest phylogenetic tree of Coleoptera to date, which represents a summary of existing phylogenetic knowledge and a defensible tree of great utility, in particular for studies at the intra-familial level, despite some shortcomings for resolving basal nodes.

The phytochemical investigation of both chloroform and ethyl acetate extracts of Centaurea microcarpa Coss. & Dur. led to the isolation of a new cyanogenic glucoside 6'-methacrylate prunasin (3) together with seven known compounds: hydroxy-11β,13-dihydro onopordaldehyde (1), β-sitosterol (2), daucosterol (4), nepetin (5), prunasin (6), astragalin (7) and 7-O-β-D-glucopyranosyl centaureidin (8). Their structures were established by spectral analysis, mainly UV, IR, ESI-MS, 1D & 2D-NMR experiments (COSY, HSQC, HMBC and ROESY).

[Aim] Fruit colours attract animal seed dispersers, yet the causes of fruit colour diversity remain controversial. The lack of knowledge of large-scale spatial patterns in fruit colours has limited our ability to formulate and test alternative hypotheses to explain fruit colour, fruit size and fruit colour diversity. We describe spatial (especially latitudinal) variation in fruit colour, colour diversity and length, and test for correlations between fruit colour, length and plant habit. [Location] Global. [Time period] Present day. [Major taxa studied] Seed plants. [Methods] We assembled a database of fruit traits for 13,178 fleshy fruited plant species spanning 136 sites around the world. To assess whether fruit colour categories correspond with spectral reflectances, we tested for clustering of hue, chroma and saturation for 236 species for which we had reflectance data. We then quantified latitudinal gradients in fruit colour, fruit length and fruit colour diversity while controlling for the effects of plant habit and whether colour categories varied with respect to average fruit size. [Results] Colour categories corresponded well with reflectance data. The tropics show high colour diversity, while red fruits progressively constitute a higher proportion of the fleshy-fruited plant community towards high latitudes. All mammal-associated colours (green, orange, brown and yellow) are more common in the tropics than at high latitudes. Fruit length also increases towards the tropics. [Main conclusions] Tropical communities tend to have diverse fruit colours, including many mammal-associated fruit colours, while high latitude communities contain a higher percentage of red-fruited species. The correlation between colour and size is strong, and some latitudinal patterns may be partly driven by changes in fruit size. Differences in geography and in the history of plant lineages in the Southern versus the Northern Hemisphere may help to explain some biogeographic patterns, but alternative hypotheses related to fruit defence, development and metabolic costs are plausible.

This study aims to identify the factors that constitute the social value of heritage in relation to sustainable tourism. To do so, this paper provides a theoretical contribution by unifying the fields of heritage management and sustainable tourism through a mixed-method approach. It showcases the social dimension of the World Heritage Site of Altamira, Spain, combining qualitative and quantitative techniques. Research findings provide information about the multiple factors determining the social value of heritage, namely: existential, aesthetic, economic, and legacy values and the risks associated with underestimating the contemporary social value. Ultimately, this research paves the way for improving normative approaches toward sustainable tourism and, offers practical solutions to the challenges faced by the Altamira and other World Heritage Sites.

Dispersal is a fundamental biological process that can be divided into three phases: release, transportation, and deposition. Determining the mechanisms of diaspore release is of prime importance to understand under which climatic conditions and at which frequency diaspores are released and transported. In mosses, wherein spore dispersal takes place through the hygroscopic movements of the peristome, the factors enhancing spore release has received little attention. Here, we determine the levels of relative humidity (RH) at which peristome movements are induced, contrasting the response of species with perfect (fully developed) and specialized (reduced) peristomes. All nine investigated species with perfect peristomes displayed a xerochastic behavior, initiating a closing movement from around 50%–65% RH upon increasing humidity and an opening movement from around 90% RH upon drying. Five of the seven species with specialized peristomes exhibited a hygrochastic behavior, initiating an opening movement under increasing RH (from about 80%) and a closing movement upon drying (from about 90%). These differences between species with hygrochastic and xerochastic peristomes suggest that spore dispersal does not randomly occur regardless of the prevailing climate conditions, which can impact their dispersal distances. In species with xerochastic peristomes, the release of spores under decreasing RH can be interpreted as an adaptive mechanism to disperse spores under optimal conditions for long-distance wind dispersal. In species with hygrochastic peristomes, conversely, the release of spores under wet conditions, which decreases their wind long-distance dispersal capacities, might be seen as a safe-site strategy, forcing spores to land in appropriate (micro-) habitats where their survival is favored. Significant variations were observed in the RH thresholds triggering peristome movements among species, especially in those with hygrochastic peristomes, raising the question of what mechanisms are responsible for such differences.

Alpine ecosystems on islands are among the most isolated on Earth, leading to very high rates of endemism. Endemic species on oceanic islands are particularly vulnerable to invasive herbivores. In the alpine zone of Tenerife, which harbors a unique endemic flora, the dominance pattern of the two most dominant species in our days (Spartocytisus supranubius and Pterocephalus lasiospermus) has shifted in the last few decades, which may be a result of increasing rabbit pressure. In this study we explore how rabbits affect the population structure, soil nutrient composition and regeneration of our two target endemics within Teide National Park. For this purpose, we established 90 plots at 30 locations. Within 13 locations we sampled permanent exclosure plots that were established between 7 and 12 years before sampling, applying three treatments (full herbivory, rabbit herbivory and no herbivory). At one site we collected 80 soil samples to evaluate changes in soil chemistry and plant growth using a greenhouse experiment. Our results show that rabbits have a negative effect on the population structure of S. supranubius, while the contrary occurs with P. lasiospermus. Rabbit presence alters soil chemistry leading to a decline in nitrogen, which affects growth in both species. The presence of rabbits leads to a dominance shift in these two keystone endemic species, altering dominance patterns in the summit scrub of Tenerife. The decline of S. supranubius could represent the example of many endemic species of this system. Thus, we call for an immediate control of rabbit population (<0.5 rabbits/ha) to protect this unique alpine endemic flora.

A direct iron(III)-catalyzed Prins-Peterson reaction involving α-substituted γ-triphenylsilyl bis-homoallylic alcohols and aldehydes is described. Thus, cis--2,7-disubstituted oxepenes were synthesized in a diastereoselective reaction using sustainable catalytic conditions (3-5 mol %). This highly productive process is the result of a cascade of three chemical events with the concomitant formation of a C-O bond, a C-C bond, and a endocyclic double bond, through a Prins cyclization followed by a Peterson-type elimination. This tandem reaction is chemoselective vs the classical Prins cyclization.