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Aim Adaptive radiation, in which successful lineages proliferate by exploiting untapped niche space, provides a popular but potentially misleading characterization of evolution on oceanic islands. Here we analyse the respective roles of members of in situ diversified vs. non-diversified lineages in shaping the main ecosystems of an archipelago to explore the relationship between evolutionary and ecological ‘success’. Location Canary Islands. Taxon Vascular plants. Methods We quantified the abundance/rarity of the native flora according to the geographical range (number of islands where present and geographical extent of the range), habitat breadth (climatic niche) and local abundance (cover) using species distribution data based on 500 × 500 m grid cells and 2000 vegetation inventories located all over the archipelago. Results Species of diversified lineages have significantly smaller geographic ranges, narrower climatic niches and lower local abundances than those of non-diversified lineages. Species rarity increased with the degree of diversification. The diversified Canarian flora is mainly comprised by shrubs. At both archipelagic and island level, the four core ecosystems (Euphorbia scrub, thermophilous woodlands, laurel forest and pine forest) were dominated by non-diversified lineages species, with diversified lineages species providing

AIMS: Understanding how biodiversity emerges and how it varies in space and time requires integration of the underlying processes that affect biodiversity at different levels of ecological organization. We present BioGEEM (BioGeographical Eco‐Evolutionary Model), a spatially explicit model that integrates theories and processes understood to drive biodiversity dynamics. We investigated the necessary degree of mechanistic complexity by exploring simulation experiments to evaluate the relative roles of the underlying processes across spatio‐temporal scales and ecological levels (e.g. populations, species, communities). LOCATION: Hypothetical oceanic islands. METHODS: BioGEEM is stochastic and grid‐based, and it integrates ecological (metabolic constraints, demography, dispersal and competition), evolutionary (mutation and speciation) and environmental (geo‐climatic dynamics) processes. Plants on oceanic islands served as a model system. We ran the simulations both with all processes on and with selected processes switched off to assess the role of each process from the emergent patterns. RESULTS: The full model was able to generate patterns matching empirical evidence and theoretical expectations. Population sizes were largest on young islands, and species, particularly endemics, better filled their potential range on young and old islands due to limited area and reduced competition. Richness peaked at mid‐elevations. The proportion of endemics was highest in old, large and isolated environments within the islands. Species and trait richness showed unimodal temporal trends. Switching off selected processes led to several unrealistic patterns, including the evolution of super‐dominant species, extremely high richness and weakened spatial diversity gradients. MAIN CONCLUSIONS: The main predictions derived from BioGEEM are: Competition has cross‐scale effects on diversity. Hump‐shaped temporal dynamics can be obtained without speciation. Endemic species seem less susceptible to extinction than native non‐endemic species. Endemism reflects stronger geographical and environmental isolation. Finally, only the integration of all implemented processes generates realistic spatio‐temporal dynamics at population, species, community and assemblage levels.

Aim The general dynamic model (GDM) proposed by Whittaker et al. (2008) has become a widely accepted theoretical framework in island biogeography. In this study, we explore whether GDM predictions hold when overall plant diversity is deconstructed into major plant families. Location 101 islands from 14 oceanic archipelagos world-wide. Methods Occurrence data for all species of nine large, cosmopolitan flowering plant families were used to test predictions derived from the GDM. We analysed the effects of island area and age on species richness as well as number and percentage of single-island endemic species per family using mixed-effect models. Results Total species and endemic richness as well as the percentage of endemic species showed the predicted hump-shaped relationship with island age. The overall pattern was mainly driven by few species-rich plant families. Varying patterns were found for individual families, some of them opposing the general trend. In most cases, native and endemic species richness peaked much earlier in the island life cycle than suggested by the GDM. The contribution of area to the explained variation of all dependent variables was much higher than that of island age. Main conclusions The results suggest that biodiversity-age relationships reported for large taxonomic groups like plants are driven by only a few species-rich clades. The way these families influence the overall patterns of species richness and endemism is related to family-specific properties, such as evolutionary history or dispersal strategies. Deviances from the GDM predictions can hence largely be explained by family characteristics and considering taxon-specific traits may help to further improve the explanatory power of the GDM. Families not following the expectations, like Orchidaceae, may be particularly valuable candidates to unveil so far neglected drivers of island biogeographical patterns.

Aim Zoogeographical regionalizations have recently seen a revived interest, which has provided new insights into biogeographical patterns. However, few quantitative studies have focused on zoogeographical regions of China. Here, we analyse zoogeographical regions for terrestrial vertebrates in China and how these regions relate to environmental and geological drivers and evaluate levels of cross-taxon congruence. Location China. Methods We applied hierarchical clustering and non-metric multidimensional scaling ordination to βsim dissimilarity matrices to delineate zoogeographical regions of China, based on the species distribution of 2102 terrestrial vertebrates in 50 × 50 km grid cells. We used generalized linear models and deviance partitioning to investigate the roles of current climate, past climate change, vegetation and geological processes in shaping the zoogeographical regions. Finally, we used Mantel and Kruskal–Wallis tests to evaluate the levels of cross-taxon congruence. Results Cluster analyses revealed 10 major zoogeographical regions: South China, the Yungui Plateau, Taiwan, North China, Northeast China, the Inner Mongolia Plateau, Northwest China, the Longzhong Plateau, the Tibetan Plateau and East Himalaya. In contrast to previous regionalizations, a major split was identified by clustering grid cell assemblages and dividing the eastern and western parts of China, followed by the northern part of China. Deviance partitioning showed that current climate and geological processes explained most of the deviance both jointly and independently. Congruence in species composition of endotherms and ectotherms was surprisingly low. Main conclusions We propose new zoogeographical regions for China based on our quantitative methods. In contrast to previous regionalizations, we consider Central China as a part of South China and identify the Longzhong Plateau and Taiwan as independent regions. While our results strongly support the notion of a broad biogeographical transition zone in East Asia, they also suggest a major south–north-oriented Palaearctic-Oriental boundary in China.

Aim The species–area relationship (SAR) is a prominent concept for predictingspecies richness and biodiversity loss. A key step in defining SARs is to accu-rately estimate the slope of the relationship, but researchers typically apply onlyone global (canonical) slope. We hypothesized that this approach is overly sim-plistic and investigated how geographically varying determinants of SARs affectspecies richness estimates of vascular plants at the global scale.Location Global.Methods We used global species richness data for vascular plants from 1032geographical units varying in size and shape. As possible determinants of geo-graphical variation in SARs we chose floristic kingdoms and biomes as biogeo-graphical provinces, and land cover as a surrogate for habitat diversity. Usingsimultaneous autoregressive models we fitted SARs to each set of determinants,compared their ability to predict the observed data and large-scale species rich-ness patterns, and determined the extent to which varying SARs differed fromthe global relationship.Results Incorporating variation into SARs improved predictions of global spe-cies richness patterns. The best model, which accounts for variation due to bio-mes, explained 46.1% of the species richness variation. Moreover, fitting SARs tobiomes produced better results than fitting them to floristic kingdoms, support-ing the hypothesis that energy availability complements evolutionary history ingenerating species richness patterns. Land cover proved to be less important thanbiomes, explaining only 36.4% of the variation, possibly owing to the high uncer-tainty in the data set. The incorporation of second-order interactions of area,land cover and biomes did not improve the predictive ability of the models.Main conclusions Our study contributes to a deeper understanding of SARsand improves the applicability of SARs through regionalization. Future modelsshould explicitly consider geographically varying determinants of SARs in orderto improve our assessment of the impact of global change scenarios on speciesrichness patterns.KeywordsBiodiversity, biome, conservation biogeography, floristic kingdom, land cover,power law, simultaneous autoregressive model, vascular plants.INTRODUCTIONThe species–area relationship (SAR) is one of the most inten-sely studied patterns in ecology and has profound importancefor conservation biogeography (Ladle & Whittaker, 2011).Applications of this concept range from mapping globalspecies richness patterns (Kier et al., 2005) and estimatingfuture extinction rates (Thomas et al., 2004; Sala et al., 2006;van Vuuren et al., 2006) to supporting conservation decision-making (Ladle & Whittaker, 2011). The theory underlying

Aim Recent advances in the availability of species distributional and highresolution environmental data have facilitated the investigation of species richness–environment relationships. However, even exhaustive distributional databases are prone to geographical sampling bias. We aim to quantify the inventory incompleteness of vascular plant data across 2377 Chinese counties and to test whether inventory incompleteness affects the analysis of richness– environment relationships and spatial predictions of species richness. Location China. Methods We used the most comprehensive database of Chinese vascular plants, which includes county-level occurrences for 29,012 native species derived from 4,236,768 specimen and literature records. For each county, we computed smoothed species accumulation curves and used the mean slope of the last 10% of the curves as a proxy for inventory incompleteness. We created a series of data subsets with different levels of inventory incompleteness by excluding successively more under-sampled counties from the full data set. We then applied spatial and non-spatial regression models to each of these subsets to investigate relationships between the species richness of subsets and environmental factors, and to predict spatial patterns of vascular plant species richness in China. Results Log10-transformed numbers of records and documented species were strongly correlated (r = 0.97). In total, 91% of Chinese counties were identified as under-sampled. After controlling for inventory incompleteness, the overall explanatory power of environmental factors markedly increased, and the strongest predictor of species richness switched from elevational range to annual wet days. Environmental models calibrated with more complete inventories yielded better spatial predictions of species richness. Main conclusions Our results indicate that inventory incompleteness strongly affects the explanatory power of environmental factors, the main determinants of species richness obtained from regression analyses, and the reliability of environment-based spatial predictions of species richness. We conclude that even large distributional databases are prone to geographical sampling bias, with far-reaching implications for the perception of and inferences about macroecological patterns.

Aim Range-restricted species account for a large proportion of global biodiversity, and many such species are highly threatened by deforestation and intensifying land use in the tropics. The effects of land use on the diversity of range-restricted species have rarely been studied and remain unknown for vascular epiphytes – diverse and important elements of tropical forests. This study analyses the vulnerability of range-restricted epiphyte species to human land use, compared to that of widespread species. Location Western Ecuador (Choco ecoregion): lowland rain forest (Bilsa, 0°21′ N 79°44′ W, 450–650 m a.s.l.) and Andean cloud forest (Otonga, 0°25′ S 79°01′ W, 1650–2250 m a.s.l.). Methods The epiphytic vegetation of 220 study plots was surveyed. Distribution data based on herbarium specimens were compiled for all identified species in order to estimate their geographical and elevational ranges as well as the climatic conditions within the species' ranges. These range characteristics were compared for species found in contiguous primary forests, primary forest fragments, secondary forests, and for isolated remnant trees in pastures. Results Of the 587 identified epiphyte species, 252 were endemic to the Choco ecoregion (42.9%). Choco endemics were not more strongly affected by human land use than non-endemics. However, small geographical ranges and narrow climatic niches were associated with higher vulnerability to habitat changes caused by land use. Epiphyte assemblages in young secondary forests had the lowest proportions of range-restricted species and were dominated by species with broad elevational ranges. Species in secondary forests occupied the broadest ranges of mean annual temperature and precipitation; species on isolated remnant trees at the lowland site inhabited on average warmer and drier geographical ranges than species in the primary forest. Main conclusions Epiphyte species with restricted geographical distributions and narrow climatic tolerances are particularly vulnerable to human-induced habitat changes, but endemism to national or biogeographical entities alone is a poor indicator of vulnerability. Instead, narrower ecological niches correlate with lower plasticity towards changes in microclimatic habitat conditions. Besides a higher extinction risk due to their small range sizes, many range-restricted species might be threatened by their lower tolerance to the impacts of human land use.

Aim We present a mechanistic niche model that integrates the demography of competing plant species in a metabolic, stochastic framework. In order to explore the model’s ability to generate multiple species and community patterns, we assessed trait composition, richness gradients and spatial distributions of species ranges and abundances of simulated communities. Location Hypothetical, sloped plane. Methods Stage-structured populations of species differing in traits and habitat requirements competed for space in a grid-based model. Demographic processes (recruitment, reproduction, mortality, dispersal) and resource competition were explicitly simulated. Demographic rates and carrying capacity followed metabolic constraints. We simulated 50 species pools until reaching stable communities. Species pools were initialized with 400 species that had random traits and habitat requirements. The habitat requirements generated potential distributions of richness, range and abundance, whereas the simulations yielded realized distributions. Results The communities assembled in the simulations consisted of species spread non-randomly within trait space. Potential species richness peaked at mid-elevations, whereas realized richness was slightly shifted towards higher elevations. For 11% of all species, the highest local abundances were found not in the most suitable habitat, but in suboptimal conditions. 53% of all species could not fill the climatically determined potential range. The ability to fill the potential range was significantly influenced by species traits (e.g. body mass and Allee effects) and species richness. Main conclusions Spatial and trait properties of surviving species and of equilibrium communities diverged from the potential distributions. Realized richness gradients were consistent both with patterns observed in nature and those expected from null models based on geometrical constraints. However, the divergences between potential and realized patterns of richness, ranges and abundances indicate the importance of demography and biotic interaction for generating patterns at species and community levels. Consequently, bias in correlative habitat models and single-species mechanistic models may arise if competition and demography are neglected. Additionally, competitive exclusion provides a mechanistic explanation for the low transferability of single-species niche models. These results confirm the usefulness of mechanistic niche models for guiding further research integrating ecological niche, community ecology and biogeography.

Aim Biogeographical regionalizations, such as zoogeographical regions, floristic kingdoms or ecoregions, represent categorizations central to many basic and applied questions in biogeography, ecology, evolution and conservation. Traditionally established by experts based on qualitative evidence, the lack of transparency and quantitative support has set constraints on their utility. The recent availability of global species range maps, novel multivariate techniques and enhanced computational power now enable a quantitative scrutiny and extension of biogeographical regionalizations that will facilitate new and more rigorous uses. In this paper we develop and illustrate a methodological roadmap for species-level biogeographical regionalizations at the global scale and apply it to mammals. Location Global. Methods We explore the relative usefulness of ordination and clustering methods and validation techniques. The performance of nine different clustering algorithms is tested at different taxonomic levels. The grain of regionalization (i.e. the number of clusters) will usually be driven by the purpose of the study, but we present several approaches that provide guidance. Results Non-metric multidimensional scaling offers a valuable first step in identifying and illustrating biogeographical transition zones. For the clustering of regions, the nine different hierarchical clustering methods varied greatly in utility, with UPGMA (unweighted pair-group method using arithmetic averages) agglomerative hierarchical clustering having consistently the best performance. The UPGMA approach allows a tree-like phenetic representation of the relative distances of regions and can be applied at different levels of taxonomic resolution. We find that the new quantitative biogeographical regions exhibit both striking similarities to and differences from the classic primary geographical divisions of the world’s biota. Specifically, our results provide evidence that the Sahara, northern Africa, the Arabian Peninsula and parts of the Middle East should be regarded as part of the Afrotropics. Further, the position of the New Guinean continental shelf, Lydekker’s Line, is supported as an appropriate border to separate the Oriental and Australian regions. Main conclusions We propose that this sort of new, quantitative delineation and relationship assessment across taxonomic and geographical grains is likely to offer opportunities for more rigorous inference in historical and ecological biogeography and conservation.

Aims We present the first global map of vascular plant species richness by ecoregion and compare these results with the published literature on global priorities for plant conservation. In so doing, we assess the state of floristic knowledge across ecoregions as described in floras, checklists, and other published documents and pinpoint geographical gaps in our understanding of the global vascular plant flora. Finally, we explore the relationships between plant species richness by ecoregion and our knowledge of the flora, and between plant richness and the human footprint – a spatially explicit measure of the loss and degradation of natural habitats and ecosystems as a result of human activities. Location Global. Methods Richness estimates for the 867 terrestrial ecoregions of the world were derived from published richness data of c. 1800 geographical units. We applied one of four methods to assess richness, depending on data quality. These included collation and interpretation of published data, use of species–area curves to extrapolate richness, use of taxon-based data, and estimates derived from other ecoregions within the same biome. Results The highest estimate of plant species richness is in the Borneo lowlands ecoregion (10,000 species) followed by nine ecoregions located in Central and South America with ≥ 8000 species; all are found within the Tropical and Subtropical Moist Broadleaf Forests biome. Among the 51 ecoregions with ≥ 5000 species, only five are located in temperate regions. For 43% of the 867 ecoregions, data quality was considered good or moderate. Among biomes, adequate data are especially lacking for flooded grasslands and flooded savannas. We found a significant correlation between species richness and data quality for only a few biomes, and, in all of these cases, our results indicated that species-rich ecoregions are better studied than those poor in vascular plants. Similarly, only in a few biomes did we find significant correlations between species richness and the human footprint, all of which were positive. Main conclusions The work presented here sets the stage for comparisons of degree of concordance of plant species richness with plant endemism and vertebrate species richness: important analyses for a comprehensive global biodiversity strategy. We suggest: (1) that current global plant conservation strategies be reviewed to check if they cover the most outstanding examples of regions from each of the world's major biomes, even if these examples are species-poor compared with other biomes; (2) that flooded grasslands and flooded savannas should become a global priority in collecting and compiling richness data for vascular plants; and (3) that future studies which rely upon species–area calculations do not use a uniform parameter value but instead use values derived separately for subregions.

Aim Although vascular epiphytes are important components of species richness and complexity of Neotropical forests, vascular epiphytes are under-represented in large scale biogeographical analyses. We studied the diversity, biogeography and floristic relationships of the epiphytic flora of the Yasuno´ region (Western Amazonia) in a Neotropical context, with special emphasis on the influence of the Andean flora on floristic composition and diversity of surrounding lowland forests. Location Western Amazonian lowland rainforest, Tiputini Biodiversity Station (0� 38¢ S7 6� 09¢ W, 230 m a.s.l., 650 ha), Yasuno´ National Park, Ecuador. Methods We compared the vascular epiphyte flora of Yasuno´ with 16 published Neotropical epiphyte inventories. Secondly, based on a floristic database with records of more than 70,000 specimens of vascular epiphytes from the Neotropics the elevational composition of eight selected inventories was analysed in detail. Results The vascular epiphyte flora of Yasuno´ is characterized by a very high species richness (313 spp.). A moderate portion of species is endemic to the Upper Napo region (c. 10%). However, this figure is much higher than previous analyses primarily based on woody species suggested. Geographical ranges of these species match with a proposed Pleistocene forest refuge. Compared with Northern and Central Amazonian sites, Western Amazonian epiphyte communities are characterized by a higher portion of montane and submontane species. Species richness of vascular epiphytes at the sites was correlated with the amount of rainfall, which is negatively correlated with the number of dry months. Main conclusion Recent and historic patterns of rainfall are the driving forces behind diversity and floristic composition of vascular epiphytes in Western Amazonia: high annual rainfall in combination with low seasonality provides suitable conditions to harbour high species richness. The proximity to the Andes, the most important centre of speciation for most Neotropical epiphytic taxa, in combination with the climatic setting has allowed a continuous supply of species richness to the region. At least for epiphytes, the borderline between the Andean and Amazonian flora is much hazier than previously thought. Moreover, the comparatively moist climate in Western Amazonia during the Pleistocene has probably led to fewer extinctions and/or more speciation than in more affected surrounding lowlands.

Aim Epiphytes contribute up to 30% to the number of vascular plant species in certain global biodiversity hotspots, e.g. the Ecuadorian Andes. However, their large scale diversity patterns are still discussed on the base of results from a few, local epiphyte inventories. Consequently, explanatory models on epiphyte diversity concentrate on the impact of local climate on small scale epiphyte species richness. Our aim was to analyse large scale elevational patterns of epiphyte diversity integrating data from different geographic scales. Location Tropical America, with special emphasis on the Ecuadorian Andes. Methods Our study is based on two data sources. First, we analysed the elevational patterns of epiphyte diversity based on the Catalogue of the Vascular Plants of Ecuador and the Libro Rojo de las Plantas Endemicas del Ecuador. Secondly, the floristic turnover between the epiphyte inventories of seven montane and four lowland study sites in the Neotropics was analysed. Results The floristic turnover between Neotropical montane epiphyte floras is higher than the one between lowland epiphyte floras. Montane study sites located only a few kilometres apart from each other show considerable differences in their epiphyte species inventories. Irrespectively of their similar dispersal mode, the floristic turnover is much higher for orchids than for Pteridophyta. The Orchidaceae are the species richest group in all of the examined 11 Neotropical epiphyte floras. At the larger scale of the Ecuadorian Flora, c. 50% of the species in the elevational zone with maximum epiphyte diversity (between 1000 and 1500 m) are orchids. Elevational patterns of epiphyte diversity strongly reflect patterns of Orchidaceae. Main conclusions Our results support the observation of a 'mid-elevation bulge' of epiphyte diversity by Gentry and Dodson. It has been frequently shown that the high humidity in mid-elevations is suitable to maintan a high epiphyte species richness. Our findings show that in addition, large scale epiphyte diversity in montane rain forest is increased by the high floristic turnover at local and regional scale. Based on the importance of Orchidaceae for epiphyte diversity, we discuss that speciation processes corresponding to the highly diverse environment are a driving force for endemism, floristic heterogeneity and consequently for large scale epiphyte species richness in montane forests.