Aim This research aimed to study if a transitional character can be postulated for the tenebrionid beetle (Coleoptera, Tenebrionidae) fauna of the Aegean Islands, and to identify ecological and historical factors responsible for observed patterns.Location Eastern Mediterranean, Aegean Islands.Methods A total of 32 Aegean Islands and 166 taxa (species and subspecies) were included in this study. In order to assess whether the Aegean tenebrionid fauna is mainly equilibrial or relictual, the importance of different eco-geographical variables (i.e. area, latitude, longitude, distance to the nearest island, distance to the mainland) in determining species richness and endemicity levels was analysed by using several statistical methods. These included single regressions, multiple regressions, and partial correlations. Cluster analysis, multidimensional scaling (MS) and discriminant function analysis (DFA) were used to quantify the similarities between the islands. Regression lines were used to study variations in the proportion of Balkan and Anatolian species. Parsimony Analysis of Endemicity (PAE) was used to study possible relationships between hierarchical species assemblages and palaeogeographical reconstructions.Results Island area accounted for most variability in species number. Distances to the nearest island and to the mainland were not identi®ed as of any statistical importance in affecting species number. The proportion of Balkan taxa sharply decreases from west to east, whereas the Anatolian taxa follow an opposite trend. The proportion of endemic taxa appears uncorrelated with island present isolation, while the proportion of subendemic taxa appears to be affected by present distance to mainland and interisland distances. Cluster analysis, MS and DFA, as well as PAE, revealed a clear faunal discontinuity between the western and central Aegean Islands on one side, and the islands close to the Anatolian coast on the other side. This discontinuity, consistent with the persistence (from Messinian to Pleistocene) of a sea barrier between these two groups of islands, strongly supports the importance of Pleistocene island con®gurations in determining present distributional patterns. Main conclusionsThe tenebrionid fauna of the Aegean Islands appears to be relictual. Most of the tenebrionid species have probably colonized the Aegean Islands by means of land-bridges during Pleistocene falls in the sea level. The palaeogeography of Pleistocene island groupings is identi®ed as responsible for present levels of endemicity and distributional patterns. An overall transitional character can be observed for the tenebrionid fauna in the study area. However, in accordance with the persistence of a deep sea barrier between the western and the eastern islands, these two groups appear to harbour very distinct faunas.

A well-known problem in numerical ecology is how to recombine presence-absence matrices without altering row and column totals. A few solutions have been proposed, but all of them present some issues in terms of statistical robustness (that is, their capability to generate different matrix configurations with the same probability) and their performance (that is, the computational effort that they require to generate a null matrix). Here we introduce the 'Curveball algorithm', a new procedure that differs from existing methods in that it focuses rather on matrix information content than on matrix structure. We demonstrate that the algorithm can sample uniformly the set of all possible matrix configurations requiring a computational effort orders of magnitude lower than that required by available methods, making it possible to easily randomize matrices larger than 10 8 cells.

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Specialisms on resources and for niches, leading to specialization, have been construed to be tantamount to speciation and vice versa, while the occurrence of true generalism in nature has also been questioned. We argue that generalism in resource use, biotope occupancy, and niche breadth not only exists, but also forms a crucial part in the evolution of specialists, representing a vital force in speciation and a more effective insurance against extinction. We model the part played by generalism and specialism in speciation and illustrate how a balance may be maintained between the number of specialists and generalists within taxa. The balance occurs as an ongoing cycle arising from turnover in the production of specialists and generalists, speciation, and species extinction. The nature of the balance depends on the type of resources exploited, biotopes, and niche space occupied. These vary between different regions and create taxonomic biases towards generalists or specialists. We envisage that the process may be sympatric/parapatric, although it is more likely initiated by allopatry driven by abiotic forces.

When dissimilarity matrices of faunistic and phylogenetic beta-diversity turnover indices are projected in dendrograms, a high frequency of ties and zero values produces trees whose topology and bootstrap support are affected by the order of areas in the original presence-absence matrix. We tested the magnitude of this bias and developed R functions to obtain consensus trees after shuffling of matrix row order and applied this algorithm to a multiscale bootstrap procedure. Our functions not only solve the bias of row order but, owing to varying support for different bootstrap scales, reveal fundamental characteristics about the structure of species assemblages.Recently, there has been a renewed interest in the study of beta-diversity metrics, mostly due to developments in partitioning widely used indices into nestedness and turnover components (Baselga 2010, Leprieur et al. 2012. Nestedness is determined by differences among areas in the ordination of species loss, whereas turnover accounts for species replacement (Baselga 2010). Recent worldwide assessments revealed that turnover indices can disclose faunistic and phylogenetic biogeographic structures (Kreft and Jetz 2010, Holt et al. 2013).Hierarchical clustering facilitates regionalization of communities by converting dissimilarity matrices into bifurcated dendrograms. Bifurcations also occur when an area shows intermediate dissimilarities between others (Legendre and Legendre 1998), as expected when different sources contribute elements to biotas. Support for nodes can be tested by bootstrap methods that re-sample random sets of the original variables (species) to construct a series of trees, and which ultimately search for concordance among subsampled trees and the original tree. Together with classical bootstrap (BP) values, approximately unbiased p-values (AU) can be obtained by multiscale bootstrap. Multiscale bootstrap alters the species number of the re-sampled datasets among different scales so as to change the probability of each species being included in the matrix. The frequency of the sites falling into their original cluster is counted at different scales, and then p-values are obtained by analyzing frequency trends. BP and AU supports can be calculated by the 'pvclust' R package (Suzuki and Shimodaira 2006).Here, we 1) illustrate how a flaw in clustering methods has important consequences for turnover analysis, 2) present R functions contributing unbiased dendrograms and bootstrap values, and 3) show that multiscale bootstrap can provide important information in biogeography.We delineated a hypothetical archipelago with two main islands (A and B), one large and one small island closely related to each main one (lA, sA, lB and sB, respectively) and three other completely intermediate islands: one large (lint), one small (sint) and one extra-small (xint). These islands hosted 31 species: 12 species occurring on A or B and a single species endemic to both lint and sint represented the basis for turnover, while 18 were widespread (Fig. 1). To test ...

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The island of Bali has several traditional Aga villages that survive under the pressures of an intense tourist industry and agricultural changes. In order to understand possible impacts on traditional ethnobotanical knowledge (TEK) in Bali, we interviewed local people living in 13 traditional villages regarding the number of known plants and their uses. We analyzed socioeconomic factors influencing change of such knowledge at both individual (informant) and community (village) level. We identified a total of 149 food and nutraceutical plants being used in the study area. Neither gender, occupation, income, nor level of formal education had a significant effect on TEK. However, informant’s age and village status were found to play an important role in the retention of TEK at an individual level. At the village level, the use of Internet/smart phones was an important predictor of cultural erosion

Although islands are model systems for investigating assembly of biological communities, long-term changes in archipelago communities are not well understood because of the lack of reliable data. By using a vast amount of floristic data we assembled a dataset of the plant species occurring on 16 islands of the Tuscan Archipelago, Italy, across two periods, 1830–1950 and 1951–2015. We collected 10,892 occurrence records for 1,831 species. We found major changes in the island plant assemblages between the two periods, with native flora significantly decreasing (−10.7%) and alien flora doubling (+132.1%) in richness. The species–area relationships demonstrated the scale-dependence of the observed changes for native and alien species. The observed floristic changes were dependent on island area, with smaller islands displaying high variability in richness and compositional changes and larger islands having more stable species assemblages. The richness of species associated with open landscapes, that had been maintained for centuries by traditional practices, markedly reduced while the number of woody species, associated with afforestation processes and invasion by alien woody plants, significantly incresed. These results demonstrate the great power of floristic studies, often available in grey literature, for understanding long-term biotic changes in insular ecosystems.