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Species diversity on the earth has increased through time. The fossil record suggests that the increase may have occurred in several stages, with perturbations caused by mass extinctions and widespread radiations. Various models for global taxonomic diversification have been proposed: equilibrium models where there is a fixed number of species that the earth can support at any time; and non-equilibrium models of two hinds, in which either an equilibrium level exists, but is never reached, or in which there is no equilibrium number at all. At present, all three models can explain the data, although the equilibrium models have been heavily criticized. Detailed reassessments of the fossil record may indicate which models are more probably correct.

Quantitative analyses of global diversity in the marine fossil record over Phanerozoic time reveal an historically ordered pattern of sequential dominance and increasing diversity. Explanatory models applied to this empirical pattern lead to irreconcilable differences of interpretation. The issue may be resolved by determining the expected distributions and limits of temporal covariation among clades generated by a random branching process. Results also challenge the claim that asymmetries in intra-clade diversity variation provide a directional arrow for the history of life.

Frances Cowper-Smith looks at the global diversity of midwives, and asks what they have in common.

Studying parasitoids can provide insights into global diversity estimates, climate change impacts, and agroecosystem service provision. However, this potential remains largely untapped due to a lack of data on how parasitoids interact with other organisms. Ecological networks are a useful tool for studying and exploiting the impacts of parasitoids, but their construction is hindered by the magnitude of undescribed parasitoid species, a sparse knowledge of host ranges, and an under-representation of parasitoids within DNA-barcode databases (we estimate

Highlights • 97 global ovine S. aureus isolates characterised using MLST and spa typing. • Majority of 261 global ovine isolates belong to one of three clonal complexes (CC). • One CC has spread across the New World; two are restricted to Europe and Africa. • Clonal complex spread matches the route and timing of sheep domestication. • Patterns of clonal diversification of sheep isolates differ from human isolates., Staphylococcus aureus is an important pathogen of many species, including sheep, and impacts on both human and animal health, animal welfare, and farm productivity. Here we present the widest global diversity study of ovine-associated S. aureus to date. We analysed 97 S. aureus isolates from sheep and sheep products from the UK, Turkey, France, Norway, Australia, Canada and the USA using multilocus sequence typing (MLST) and spa typing. These were compared with 196 sheep isolates from Europe (n = 153), Africa (n = 28), South America (n = 14) and Australia (n = 1); 172 bovine, 68 caprine and 433 human S. aureus profiles. Overall there were 59 STs and 87 spa types in the 293 ovine isolates; in the 97 new ovine isolates there were 22 STs and 37 spa types, including three novel MLST alleles, four novel STs and eight novel spa types. Three main CCs (CC133, CC522 and CC700) were detected in sheep and these contained 61% of all isolates. Four spa types (t002, t1534, t2678 and t3576) contained 31% of all isolates and were associated with CC5, CC522, CC133 and CC522 respectively. spa types were consistent with MLST CCs, only one spa type (t1403) was present in multiple CCs. The three main ovine CCs have different but overlapping patterns of geographical dissemination that appear to match the location and timing of sheep domestication and selection for meat and wool production. CC133, CC522 and CC700 remained ovine-associated following the inclusion of additional host species. Ovine isolates clustered separately from human and bovine isolates and those from sheep cheeses, but closely with caprine isolates. As with cattle isolates, patterns of clonal diversification of sheep isolates differ from humans, indicative of their relatively recent host-jump.

What we understand by the simple term ‘city’ is in fact describing highly diverse domains: different economies, demographics, ways of living, land uses, built-up morphologies, among other things. The built landscape alone ranges from low-density, one-storey suburban settlements to high-density accumulations of skyscrapers. Models have repeatedly attempted to describe these various ‘city’ manifestations and to understand the processes that shape these spatial appearances and patterns. In this paper we analyze the morphological-spatial configurations of urban landscapes. We empirically examine 110 cities distributed around the globe. By using the Local Climate Zones (LCZs) classification scheme, we quantitatively describe morphologic variances of the built landscape within cities. We find seven city types (clusters) that capture the global diversity of spatial urban configurations. These seven types testify in parts to common geographic-cultural spaces. Some are largely congruent with well-known spatial units such as Europe or the Islamic world. In contrast to theoretical city models, however, we also find clusters that are more spatially complex such as African-American or Asian-African clusters. On the one hand, the study confirms that similar cultural, socio-economic, demographic or political conditions in fact do produce similar morphologic-spatial urban configurations. On the other hand, it also shows that there exist similar morphological configurations across geographic-cultural spaces.

Genetic diversity for the alleles of gliadin-coding loci was studied with 465 durum wheat accessions from 42 countries. A total of 108 alleles were identified for four loci; 60 alleles were described for the first time. Broad diversity of rare gliadin-coding alleles was observed. The highest genetic diversity was characteristic of durum wheat accessions from the Middle East, Trans-Caucasia, the Pyrenean Peninsula, and the Balkans. Two genetically isolated ancient branches of durum wheat were isolated. A “southern” branch included mostly accessions from the Mediterranean region, the Middle East, and Trans-Caucasia. A “northern” branch included Russian and Ukrainian durum wheat accessions and varieties obtained on their basis. An additional group included durum wheat accessions that had been obtained in several past decades on the basis of the material of international breeding centers (CIMMYT and ICARDA) and had low genetic diversity.

International audience; AimGeographic spread and range expansion of species into novel environments may merge originally separated species assemblages, yet the possible drivers of geographic heterogeneity in host-parasite associations remain poorly understood. Here, we examine global patterns in the parasite assemblages of two rat species and explore the role of parasite acquisition from local pools of host species.LocationGlobal.Methods We compiled a global data set of helminth parasites (n = 241 species) from two rat species (Rattus rattus species complex, R. norvegicus) and, concomitantly, from all other mammal species known to be infected by the same parasites. We used an inverse Bayesian modelling approach to explicitly link species-level to community-level infestation probabilities at different geographic scales and alleviate the shortcoming of sampling bias.ResultsPatterns of species richness and turnover of parasites in the two focal rat species revealed clear biogeographic structure with lowest species richness and most distinct assemblages in Madagascar and highest species richness and least distinct assemblages in the Palaearctic region. Parasite species richness and turnover across regions were correlated for the two focal hosts, although they were associated with distinct assemblages within regions. Infection probability of a focal host with any given parasite was clearly related to infection probability of the local species pool of wildlife hosts with that same parasite. Infection probability of other mammal species infected with these parasite species, in turn, decreased with their taxonomic distance to the genus Rattus.Main conclusionsOur study demonstrates the importance of spillover of parasites from local wildlife hosts to invasive rats on global patterns of host-parasite associations. Considering both changes in local pools of host species and the global distributions of parasite and pathogen diversity in consistent model frameworks may therefore advance the forecasting of species-level infestation patterns and the possible risk of disease emergence from local to global scale.

Background Measuring the structural diversity of compound databases is relevant in drug discovery and many other areas of chemistry. Since molecular diversity depends on molecular representation, comprehensive chemoinformatic analysis of the diversity of libraries uses multiple criteria. For instance, the diversity of the molecular libraries is typically evaluated employing molecular scaffolds, structural fingerprints, and physicochemical properties. However, the assessment with each criterion is analyzed independently and it is not straightforward to provide an evaluation of the “global diversity”. Results Herein the Consensus Diversity Plot (CDP) is proposed as a novel method to represent in low dimensions the diversity of chemical libraries considering simultaneously multiple molecular representations. We illustrate the application of CDPs to classify eight compound data sets and two subsets with different sizes and compositions using molecular scaffolds, structural fingerprints, and physicochemical properties. Conclusions CDPs are general data mining tools that represent in two-dimensions the global diversity of compound data sets using multiple metrics. These plots can be constructed using single or combined measures of diversity. An online version of the CDPs is freely available at: https://consensusdiversityplots-difacquim-unam.shinyapps.io/RscriptsCDPlots/.Graphical AbstractConsensus Diversity Plot is a novel data mining tool that represents in two-dimensions the global diversity of compound data sets using multiple metrics. Electronic supplementary material The online version of this article (doi:10.1186/s13321-016-0176-9) contains supplementary material, which is available to authorized users.