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Background: Contemporary and projected shifts in global fire regimes highlight the importance of understanding how fire affects ecosystem function and biodiversity across taxa and geographies. Pyrodiversity, or heterogeneity in fire history, is often an important driver of biodiversity, though it has been largely overlooked until relatively recently. In this paper, we synthesise previous research to develop a theoretical framework on pyrodiversity–biodiversity relationships and propose future research and conservation management directions. Theoretical Framework: Pyrodiversity may affect biodiversity by diversifying available ecological niches, stabilising community networks and/or supporting diverse species pools available for post‐fire colonisation. Further, pyrodiversity's effects on biodiversity vary across different spatial, temporal and organismal scales depending on the mobility and other life history traits of the organisms in question and may be mediated by regional eco‐evolutionary factors such as historical fire regimes. Developing a generalisable understanding of pyrodiversity effects on biodiversity has been challenging, in part because pyrodiversity can be quantified in various ways. Applying the Pyrodiversity Concept: Exclusion of Indigenous fire stewardship, fire suppression, increased unplanned ignitions and climate change have led to dramatic shifts in fire regimes globally. Such shifts include departures from historic levels of pyrodiversity and add to existing challenges to biodiversity conservation in fire‐prone landscapes. Managers navigating these challenges can be aided by targeted research into observed contemporary pyrodiversity–biodiversity relationships as well as knowledge of historical reference conditions informed by both Indigenous and local ecological knowledge and western science. Future Research Directions: Several promising avenues exist for the advancement of pyrodiversity science to further both theoretical and practical goals. These lines of investigation include but are not limited to (1) testing the increasing variety of pyrodiversity metrics and analytical approaches; (2) assessing the spatial and temporal scale‐dependence of pyrodiversity's influence; (3) reconstructing historical pyrodiversity patterns and developing methods for predicting and/or promoting future pyrodiversity; and (4) expanding the focus of pyrodiversity science beyond biodiversity to better understand its influence on ecosystem function and processes more broadly. [ABSTRACT FROM AUTHOR]

Aim: The global distribution and diversity of mites, including the species rich and highly host plant‐specific eriophyoid mites, are important questions in biogeography and biodiversity conservation. Here we critique the paper of Li et al. (2023) titled 'Global patterns and drivers of herbivorous eriophyoid mite species diversity'. Location: Global Taxon: Eriophyoid mites (Acari: Eriophyoidea) Methods: We assert that the data set utilized (less than 4,500 eriophyoid species) consisted of only the described extant species, not all extant species. We then provide evidence that the utilised data set represents only a small proportion of the likely global total of eriophyoid species and therefore provides a far from complete representation of their global distribution. Results: Most collections of extant eriophyoid mites have been conducted in temperate regions where most taxonomic specialists have been active, and not in the largely unstudied tropical regions which contain a very substantial majority of all plant diversity. Most undescribed eriophyoid diversity is therefore highly likely to be found in the tropics. This suggests that the global modelling analyses of Li et al. (2023) were very likely applied to a highly inaccurate data set. Main Conclusions: The actual global distribution and total number of eriophyoid mite species can only be more reliably estimated by systematic taxonomic studies that cover the entire global distribution of plant diversity, which implies a strong focus on the tropical regions. [ABSTRACT FROM AUTHOR]

Aim: The latitudinal diversity gradient (LDG) is a consequence of evolutionary and ecological mechanisms acting over long history, and thus is best investigated with organisms that have rich fossil records. However, combined neontological‐palaeontological investigations are mostly limited to large, shelled invertebrates, which keeps our mechanistic understanding of LDGs in its infancy. This paper aims to describe the modern meiobenthic ostracod LDG and to explore the possible controlling factors and the evolutionary mechanisms of this large‐scale biodiversity pattern. Location: Present‐day Western North Atlantic. Taxon: Ostracoda. Methods: We compiled ostracod census data from shallow‐marine environments of the western North Atlantic Ocean. Using these data, we documented the marine LDG with multiple metrics of alpha, beta (nestedness and turnover) and gamma diversity, and we tested whether macroecological patterns could be governed by different environmental factors, including temperature, salinity, dissolved oxygen, pH and primary productivity. We also explored the geologic age distribution of ostracod genera to investigate the evolutionary mechanisms underpinning the LDG. Results: Our results show that temperature and climatic niche conservatism are important in setting LDGs of these small, poorly dispersing organisms. We also found evidence for some dispersal‐driven spatial dynamics in the ostracod LDG. Compared to patterns observed in marine bivalves, however, dispersal dynamics were weaker and they were bi‐directional, rather than following the 'out‐of‐the‐tropics' model. Main conclusions: Our detailed analyses revealed that meiobenthic organisms, which comprise two‐thirds of marine diversity, do not always follow the same rules as larger, better‐studied organisms. Our findings suggest that the understudied majority of biodiversity may be more sensitive to climate than well‐studied, large organisms. This implies that the impacts of ongoing Anthropocene climatic change on marine ecosystems may be much more serious than presently thought. [ABSTRACT FROM AUTHOR]

Aim In contrast to the attention given to southern Europe both as a centre of speciation and differentiation and as a Pleistocene refugium of Western Palaearctic taxa, North Africa has been relatively neglected. In this paper, we set out to address this shortfall. Location North-West Africa and the Mediterranean. Methods We reviewed the existing literature on the biogeography of North Africa, and carried out analyses of species distribution data using parsimony, nestedness and co-occurrence methods. Results In many cases, distribution patterns of non-flying mammals, bats, amphibians, reptiles, butterflies, zygaenid moths and odonates demonstrated important biogeographical affinities between Europe and North Africa at the species level. On the other hand, species co-occurrence, nestedness and parsimony analysis also revealed some deep splits between the Maghreb and Europe; yet even in these cases the closest affinities were found between the Iberian Peninsula and the Maghreb. Furthermore, North Africa harbours the highest proportion of endemic taxa (13.7%) across all groups analysed. Many molecular studies demonstrated a strong genetic cohesiveness between North Africa and Europe despite the potential barrier effect of the Mediterranean Sea. In other taxa, however, remarkable splits were detected. In addition, southern European genetic lineages were often nested within North African clades, and many taxa showed exceptionally high genetic variability and differentiation in this region. Main conclusions The Maghreb was an important differentiation and speciation centre for thermophilic organisms during the Pliocene and Pleistocene with high relevance as a colonization source for Europe. The regions around the sea straits of Gibraltar and Sicily have acted as important biogeographical links between North Africa and Europe at different times. [ABSTRACT FROM AUTHOR]

Aim Species distribution models have been widely used to tackle ecological, evolutionary and conservation problems. Most species distribution modelling techniques produce continuous suitability predictions, but many real applications (e.g. reserve design, species invasion and climate change impact assessment) and model evaluations require binary outputs, and thresholds are needed for these transformations. Although there are many threshold selection methods for presence/absence data, it is unclear whether these are suitable for presence-only data. In this paper, we investigate mathematically and empirically which of the existing threshold selection methods can be used confidently with presence-only data. Location We used real spatially explicit environmental data derived from the western part of the state of Victoria, south-eastern Australia, and simulated species distributions within this area. Methods Thirteen existing threshold selection methods were investigated mathematically to see whether the same threshold can be produced using either presence/absence data or presence-only data. We further adopted a simulation approach, created many virtual species with differing prevalences in a real landscape in south-eastern Australia, generated data sets with different proportions of pseudo-absences, built eight types of models with four modelling techniques, and investigated the behaviours of four threshold selection methods in these situations. Results Three threshold selection methods were not affected by pseudo-absences, including max SSS (which is based on maximizing the sum of sensitivity and specificity), the prevalence of model training data and the mean predicted value of a set of random points. Max SSS produced higher sensitivity in most cases and higher true skill statistic and kappa in many cases than the other methods. The other methods produced different thresholds from presence-only data to those determined from presence/absence data. Main conclusions Max SSS is a promising method for threshold selection when only presence data are available. [ABSTRACT FROM AUTHOR]

Aim: The Last Glacial Maximum (LGM) remains an enigmatic period in southeast Australia due to the limited spatial and temporal resolution of its palaeoclimatic records. A major feature of the LGM landscape was the existence of the Bassian Land Bridge, joining Tasmania with the mainland of Australia during periods of low sea level, and potentially facilitating increased biotic movement between these regions. To better understand biogeographical changes on the land bridge and in southeast Australia generally during the LGM, we present a 35 ka‐year palaeoecological record from one of the larger islands of Bass Strait. Location: Bass Strait, southeast Australia. Taxon: Eucalyptus, Poaceae, Monotoca, Myriophyllum, Zygnemataceae, Botryococcus, Pediastrum. Methods: Pollen, charcoal, and non‐pollen palynomorphs were analysed in a 1.75‐m sediment core from truwana/Cape Barren Island, Bass Strait, to reconstruct changes in vegetation, fire regimes and lake levels on the Bassian Land Bridge. Results were then compared to existing palaeoenvironmental studies in the region to develop a broader context of the prevailing land bridge environment and the potential influence on biotic dispersals in Australia during the last glacial period. Results: Results suggest a major vegetation shift on the Bassian Land Bridge in response to the establishment of the LGM climate, with grassland expansion at the expense of woodland from ~29–11 ka. Floristic richness, biomass burned and lake levels also markedly decreased through this period, with the driest interval being ~25–18 ka. Dryland herbaceous taxa dispersed between the mainland and Tasmania when the landbridge was fully exposed. Main conclusions: In agreement with previous studies, our results show that the dry grassland that dominated southeast Australia (and Southern Hemisphere mid‐latitude areas) during the LGM also extended across the Bassian Land Bridge. The prevailing environment on the land bridge is likely to have exerted a selective influence on biotic dispersals in Australia during glacial periods. [ABSTRACT FROM AUTHOR]

Tropical climates and the biodiversity associated with them have long interested natural historians. Alexander von Humboldt inspired a generation of scientists, such as Charles Darwin and Alfred Russel Wallace, to observe and study tropical ecosystems. More recently, the mid-20th century saw Theodosius Dobzhansky and Daniel Janzen lay the foundations for studying adaptation to tropical climates. Now in the 21st century, we are beginning to realize the threats posed by current and future climate change to tropical populations which, despite relatively low levels of projected warming for low-latitude regions, face potentially significant detrimental impacts. Building on the insights of researchers in decades and centuries past, improved understanding of tropical ecology, evolution and biogeography will help us to conceive how future global change will impact on biodiversity. [ABSTRACT FROM AUTHOR]

Aim: The unique biodiversity in the Red Sea is the result of complex ecological and evolutionary processes driven by Pleistocene climatic change. Here we investigate the species diversity, phylogenetic relationships and phylogeographical patterns of giant clams in the Western Indian Ocean (WIO) and the Red Sea to explore scenarios of marine speciation in this under‐studied region. Location: Mozambique Channel, Madagascar, and the Mascarene Islands (WIO); the Farasan Islands (Red Sea). Taxon: Giant clams of the genus Tridacna (Cardiidae: Tridacninae). Methods: Giant clams were sampled as complete organisms or through underwater biopsies. Nuclear (28S) and mitochondrial (16S and COI) DNA sequences were subjected to Bayesian and maximum likelihood analyses to generate a phylogenetic hypothesis for all known species within the genus Tridacna. Bayesian inference with molecular and fossil calibration was used to infer their colonization history. Results: From the 10 genetically distinct clades recovered from the analyses of 253 sequenced specimens, five distinct Tridacna lineages were sampled, three of which were endemics of the WIO and the Red Sea. Each lineage corresponded to a distinct species, except one grouping the two formerly known WIO endemics, T. lorenzi and T. rosewateri. This lineage clustered with two other well‐supported lineages: the Red Sea endemic T. squamosina, and a previously unrecognized lineage, restricted to the WIO, for which we resurrect the long‐forgotten name T. elongatissima Bianconi, 1856. For the two other species sampled (T. maxima and T. squamosa), contrasting phylogeographical patterns were observed. Main conclusions: Our data confirm the validity of the species T. rosewateri, a WIO endemic genetically indistinguishable from T. lorenzi, which should be considered a junior synonym. The phylogenetic placement of the newly resurrected T. elongatissima provides insights into the probable origin of T. squamosina, which split from its sister species no later than 2 Ma, likely during Middle Pleistocene glacial periods. Two scenarios are discussed. Our results also suggest that T. maxima invaded the Red Sea more recently and that contemporary gene flow between Red Sea and WIO T. maxima is highly restricted. The deep Red Sea partition observed in T. squamosa suggests a much older divergence and raises the question of a possible cryptic lineage. [ABSTRACT FROM AUTHOR]

Aim: Temporal dynamics of biodiversity along tropical elevational gradients are unknown. We studied seasonal changes of Lepidoptera biodiversity along the only complete forest elevational gradient in the Afrotropics. We focused on shifts of species richness patterns, seasonal turnover of communities and seasonal shifts of species' elevational ranges, the latter often serving as an indicator of the global change effects on mountain ecosystems. Location: Mount Cameroon, Cameroon. Taxon: Butterflies and moths (Lepidoptera). Methods: We quantitatively sampled nine groups of Lepidoptera by bait‐trapping (16,800 trap‐days) and light‐catching (126 nights) at seven elevations evenly distributed along the elevational gradient from sea level (30 m a.s.l.) to timberline (2,200 m a.s.l.). Sampling was repeated in three seasons. Results: Altogether, 42,936 specimens of 1,099 species were recorded. A mid‐elevation peak of species richness was detected for all groups but Eupterotidae. This peak shifted seasonally for five groups, most of them ascending during the dry season. Seasonal shifts of species' elevational ranges were mostly responsible for these diversity pattern shifts along elevation: we found general upward shifts in fruit‐feeding butterflies, fruit‐feeding moths and Lymantriinae from beginning to end of the dry season. Contrarily, Arctiinae shifted upwards during the wet season. The average seasonal shifts of elevational ranges often exceeded 100 m and were even several times higher for numerous species. Main conclusions: We report seasonal uphill and downhill shifts of several lepidopteran groups. The reported shifts can be driven by both delay in weather seasonality and shifts in resource availability, causing phenological delay of adult hatching and/or adult migrations. Such shifts may lead to misinterpretations of diversity patterns along elevation if seasonality is ignored. More importantly, considering the surprising extent of seasonal elevational shifts of species, we encourage taking account of such natural temporal dynamics while investigating the global climate change impact on communities of Lepidoptera in tropical mountains. [ABSTRACT FROM AUTHOR]

Mountains are arguably Earth's most striking features. They play a major role in determining global and regional climates, are the source of most rivers, act as cradles, barriers and bridges for species, and are crucial for the survival and sustainability of many human societies. The complexity of mountains is tightly associated with high biodiversity, but the processes underlying this association are poorly known. Solving this puzzle requires researchers to generate more primary data, and better integrate available geological and climatic data into biological models of diversity and evolution. In this perspective, we highlight emerging insights, which stress the importance of mountain building through time as a generator and reservoir of biodiversity. We also discuss recently proposed parallels between surface uplift, habitat formation and species diversification. We exemplify these links and discuss other factors, such as Quaternary climatic variations, which may have obscured some mountain‐building evidence due to erosion and other processes. Biological evolution is complex and the build‐up of mountains is certainly not the only explanation, but biological and geological processes are probably more intertwined than many of us realize. The overall conclusion is that geology sets the stage for speciation, where ecological interactions, adaptive and non‐adaptive radiations and stochastic processes act together to increase biodiversity. Further integration of these fields may yield novel and robust insights. [ABSTRACT FROM AUTHOR]

Aim: Predicting future changes in species richness in response to climate change is one of the key challenges in biogeography and conservation ecology. Stacked species distribution models (S‐SDMs) are a commonly used tool to predict current and future species richness. Macroecological models (MEMs), regression models with species richness as response variable, are a less computationally intensive alternative to S‐SDMs. Here, we aim to compare the results of two model types (S‐SDMS and MEMs), for the first time for more than 14,000 species across multiple taxa globally, and to trace the uncertainty in future predictions back to the input data and modelling approach used. Location: Global land, excluding Antarctica. Taxon: Amphibians, birds and mammals. Methods: We fitted S‐SDMs and MEMs using a consistent set of bioclimatic variables and model algorithms and conducted species richness predictions under current and future conditions. For the latter, we used four general circulation models (GCMs) under two representative concentration pathways (RCP2.6 and RCP6.0). Predicted species richness was compared between S‐SDMs and MEMs and for current conditions also to extent‐of‐occurrence (EOO) species richness patterns. For future predictions, we quantified the variance in predicted species richness patterns explained by the choice of model type, model algorithm and GCM using hierarchical cluster analysis and variance partitioning. Results: Under current conditions, species richness predictions from MEMs and S‐SDMs were strongly correlated with EOO‐based species richness. However, both model types over‐predicted areas with low and under‐predicted areas with high species richness. Outputs from MEMs and S‐SDMs were also highly correlated among each other under current and future conditions. The variance between future predictions was mostly explained by model type. Main conclusions: Both model types were able to reproduce EOO‐based patterns in global terrestrial vertebrate richness, but produce less collinear predictions of future species richness. Model type by far contributes to most of the variation in the different future species richness predictions, indicating that the two model types should not be used interchangeably. Nevertheless, both model types have their justification, as MEMs can also include species with a restricted range, whereas S‐SDMs are useful for looking at potential species‐specific responses. [ABSTRACT FROM AUTHOR]

Aim: Our objective is to analyse global‐scale patterns of mountain biodiversity and the driving forces leading to the observed patterns. More specifically, we test the 'mountain geobiodiversity hypothesis' (MGH) which is based on the assumption that it is not mountain‐uplift alone which drives the evolution of mountain biodiversity, but rather the combination of geodiversity evolution and Neogene and Pleistocene climate changes. We address the following questions: (a) Do areas of high geodiversity and high biodiversity in mountains overlap, that is can mountain geodiversity predict mountain biodiversity? (b) What is the role of Pleistocene climate change in shaping mountain biodiversity? (c) Did diversification rate shifts occur predominantly with the onset of more pronounced climate fluctuations in the late Neogene and Pleistocene fostering a 'species pump' effect, as predicted by the MGH? Location: Global. Taxon: Vascular plants. Methods: We used generalized linear models to test to what extent vascular plant species diversity in mountains is explained by net primary productivity (NPP), geodiversity and Pleistocene climate fluctuations (i.e. changes in temperature between the Last Glacial Maximum [LGM] and today). In addition, we compiled dates of diversification rate shifts from mountain systems and investigated whether these shifts occurred predominantly before or after the global major climatic fluctuations of the late Neogene and Pleistocene. Results: Both NPP and elevation range show a positive relationship, whereas Pleistocene climatic fluctuations show a negative impact on plant species diversity. The availability of climatic niche space during the LGM differs markedly among mountain systems. Shifts to higher diversification rates or starts of radiations showed the highest concentration from the late Miocene towards the Pleistocene, supporting the MGH. The most commonly inferred drivers of diversification were key innovations, geological processes (uplift) and climate. Main conclusions: Our analyses point towards an important role of historical factors on mountain plant species richness. Mountain systems characterized by small elevational ranges and strong modifications of temperature profiles appear to harbour fewer radiations, and fewer species. In contrast, mountain systems with the largest elevational ranges and stronger overlap between today´s and LGM temperature profiles are also those where most plant radiations and highest species numbers were identified. [ABSTRACT FROM AUTHOR]

Aim: The summits of mountain ranges at mid‐latitude in the Northern Hemisphere share many ecological properties with the Arctic, including comparable climates and similar flora. We hypothesize that the orogeny during the Oligocene‐Miocene combined with global cooling led to the origin and early diversification of cold‐adapted plant lineages in these regions. Before the establishment of the Arctic cryosphere, adaptation and speciation in high elevation areas of these mountain ranges may have led to higher species richness compared to the Arctic. Subsequent colonization from mid‐latitude mountain ranges to the Arctic may explain similar but poorer flora. Location: Arctic‐Alpine regions of the Northern Hemisphere. Methods: We mapped the cold climate in the Northern Hemisphere for most of the Cenozoic (60 Ma until present) based on paleoclimate proxies coupled with paleoelevations. We generated species distribution maps from occurrences and regional atlases for 5,464 plant species from 756 genera occupying cold climates. We fitted a generalized linear model to evaluate the association between cold‐adapted plant species richness and environmental, as well as geographic variables. Finally, we performed a meta‐analysis of studies which inferred and dated the ancestral geographic origin of cold‐adapted lineages using phylogenies. Results: We found that the subalpine‐alpine areas of the mid‐latitude mountain ranges comprise higher cold‐adapted plant species richness than the Palearctic and Nearctic polar regions. The topo‐climatic reconstructions indicate that the cold climatic niche appeared in mid‐latitude mountain ranges (42–38 Ma), specifically in the Himalayan region, and only later in the Arctic (22–18 Ma). The meta‐analysis of the dating of the origin of cold‐adapted lineages indicates that most clades originated in central Asia between 39–7 Ma. Main conclusions: Our results support the hypothesis that the orogeny and progressive cooling in the Oligocene‐Miocene generated cold climates in mid‐latitude mountain ranges before the appearance of cold climates in most of the Arctic. Early cold mountainous regions likely allowed for the evolution and diversification of cold‐adapted plant lineages followed by the subsequent colonization of the Arctic. Our results follow Humboldt's vision of integrating biological and geological context in order to better understand the processes underlying the origin of arctic‐alpine plant assemblages. [ABSTRACT FROM AUTHOR]

Abstract: Aim: Drivers of intraspecific biodiversity include past climate‐driven range shifts and contemporary ecological conditions mediating connectivity, but these are rarely integrated in a common comprehensive approach. This is particularly relevant for marine organisms, as ocean currents strongly influence population isolation or connectivity, keeping or diluting the signatures left by past climates. Here we ask whether the coupling between past range shifts and contemporary connectivity explain the extant gene pools of Laminaria ochroleuca, a large brown alga structuring important marine forests from shallow to deep infralittoral grounds. Location: Northeastern Atlantic Ocean. Taxon: Laminaria ochroleuca. Methods: We estimated population genetic diversity and structure of L. ochroleuca across its entire distribution range using 15 polymorphic microsatellite markers. This was compared with the outcomes of a palaeoclimatic model predicting latitudinal and depth range shifts from the Last Glacial Maximum (LGM) to the present. Genetic differentiation was further compared with potential connectivity inferred with a biophysical model developed with high‐resolution data from HYCOM (Hybrid Coordinate Ocean Model). Results: The biogeographical distribution of genetic variability showed overall agreement with the predictions from independently inferred past range shifts. Multiple regions of persistence were identified in deep and upwelling settings at the lowest latitudes of the current species distribution, where higher and unique genetic diversity was retained. The biophysical model revealed that despite the possibility of long‐distance migration, contemporary oceanographic barriers strongly restrict connectivity of isolated genetic lineages. Main conclusions: Integrating different processes at biogeographical scales explained the extant gene pools of marine forests of L. ochroleuca. Low‐latitude genetic relics harbour a disproportional evolutionary significance, persisting as ancient populations in isolated deep and upwelling climate refugia. Their inferred rates of dispersal may be insufficient to accommodate anticipated climate warming. [ABSTRACT FROM AUTHOR]

Abstract: Aim: Island tropical montane cloud forests (TMCFs) host a disproportionally high share of the global biodiversity and provide critical ecosystem services to vulnerable insular societies. However, this ecosystem is imperilled by anthropogenic impacts including climate change that might push TMCFs towards higher elevations. The elevation at which TMCFs start varies greatly among islands and may depend on topographically driven local climate, which may in turn be influenced by large‐scale climate. Thus, a necessary prerequisite to assessing the vulnerability of island TMCFs to climate change is to determine the role of island features versus regional climate in influencing local climate at the lower TMCF ecotone. Location: Tropical islands. Methods: An extensive literature review of the elevation at which island TMCFs start was undertaken. This elevation was modelled as a function of the altitude of the lifting condensation level (LCL) imposed by regional climate, island maximum elevation and upwind forest loss over the past 15 years. Results: The elevation of the lower TMCF boundary was found to have been reported for 93 islands worldwide. TMCFs starts from as low as 300 m on the small islands of Kosrae (Micronesia; maximum elevation = 628 m) and Aneityum (Vanuatu; 852 m) to a maximum of 1,600 m on the large islands of Cuba (1,974 m) and Hispaniola (3,175 m), providing a spectacular example of the ‘Massenerhebung effect’. Both regional climate (LCL altitude) and island features (maximum elevation) influenced the elevation of the lower TMCF boundary, and these variables together accounted for 79% of the variance. Main conclusions: On islands, climate change is likely to cause significant but small upslope shifts of the LCL and subsequently of TMCF lower boundary elevation in the future (+4.4 m for each 1°C increase in temperature). TMCF clearing and biological invasions might appear to be more pressing threats. [ABSTRACT FROM AUTHOR]

Aim: Here, I investigate galagid diversification and current distribution in the context of major climatic and geological events in sub-Saharan Africa. Given their widespread distribution and presence in a large range of diverse habitats, galagids represent an excellent group to investigate the role of forest contraction and expansion on biological diversification in sub-Saharan Africa. Location: Sub-Saharan Africa (Afrotropical Region). Methods: I assembled a supermatrix including 53 nuclear loci and three mitochondrial markers for 94% of the galagid species currently recognized. Bayesian and maximum likelihood methods were used to infer phylogenetic relationships and times of divergence within the family. Ancestral ranges were estimated using several methods, including 'BioGeoBEARS' and rasp. Results: Phylogenetic analyses corroborated previous results regarding the evolutionary history of this family: (1) early origin of the family soon after the Eocene-Oligocene boundary; (2) dwarf galagos (Galagoides spp.) represent a polyphyletic group with two well-defined clades, one in central-west Africa and one in the east; and (3) divergences within galagids are relatively old with most genera already present by the Late Miocene. The biogeographical analysis indicates central African origins and subsequent expansion to the east in the Early- Middle Miocene. An expansion to the northern and southern savannas occurred between the Late Pliocene and the Middle Pleistocene. Main conclusions: The results of this study clarify several questions related to the evolutionary history of the Galagidae in the context of sub-Saharan African biogeography. This study suggests that galagid evolution and diversification was affected by three major climatic episodes: (1) the global cooling and forest contraction in the Early Oligocene, (2) the forest expansion and the uplift of the African rifts in the Miocene and (3) the aridification and extension of open woodlands and savannas in the Late Miocene and Plio-Pleistocene. [ABSTRACT FROM AUTHOR]

Aim To describe the distribution of biodiversity and biogeographical patterns of intertidal organisms in southern temperate and polar waters. We hypothesized that there would be differences in community structure between the Antarctic, which is most affected by ice, and the sub-Antarctic and other neighbouring regions. We also hypothesized that rafting and West Wind Drift will be the significant drivers of biogeographical patterns. Additionally, the size, age, isolation, volcanic or glacial history of a region and the presence of large, beach dwelling, mammals and birds would all play a role in determining the level of biodiversity observed. Location South Atlantic, Indian and Pacific Oceans and the Southern Ocean. Methods We examined all available intertidal records from the Antarctic and sub-Antarctic with additional data from neighbouring regions for comparison and context. We compiled 3902 occurrences of 1416 species of high southern latitude intertidal organisms from 229 locations and used PRIMER 6 to perform multivariate statistical analyses. Results The Antarctic and sub-Antarctic are shown to be distinct biogeographical regions, with patterns driven by a small number of widely distributed species. These wide-ranging molluscs and macroalgae dominate the biogeographical structure of the Southern Ocean intertidal, most likely as a result of rafting in the Antarctic Circumpolar Current. East Antarctic intertidal habitats are potentially isolated by the Ross and Weddell Sea ice shelves but represent a great unknown in this biogeographical scheme. Main Conclusions The view that the Antarctic intertidal is a lifeless desert does not hold true, with Antarctic Peninsula intertidal communities being richer and more diverse than those in southern South America and the sub-Antarctic islands. Changing conditions in the Antarctic and sub-Antarctic intertidal mean that a representative baseline is needed (acquired through standardized and quantitative sampling) to assess future changes and to detect any invasive species. [ABSTRACT FROM AUTHOR]

Aim The aim of this study was to test the link between climatic niche dynamics and species diversification in Anolis on islands and on the mainland. We tested the hypotheses that lineages in warmer climates and with narrow climate niches diversified more than lineages in cold climates and with broad climate niches. We also tested the hypothesis that species-rich clades exhibit greater niche diversity than species-poor clades. Location Neotropics. Methods We collated occurrence records for 328 Anolis species to estimate niche breadth, niche position and occupied niche space (as a proxy for niche diversity). We compared niche breadth between insular and mainland Anolis species and among Anolis clades, controlling for the potential confounding effect of range size. Using two approaches (clade-based and QuaSSE) we explored the association between niche metrics and diversification rates in Anolis lizards. Results We found that Caribbean Anolis had a narrower niche breadth and niche space occupation compared to mainland anoles after controlling for range size differences. There was a significant association between niche traits (mean niche position and niche breadth) and diversification in anoles. Anole lineages with narrow niche breadths and that occupy warmer areas exhibited higher speciation rates than those with broader niche breadths and that occupy cold areas. Similarly, clades with higher total diversification exhibit more niche diversity than clades with lower total diversification. Main conclusions Climatic niche attributes play a role in anole diversification with some differences between mainland and insular anole lineages. Climatic niche differences between regions and clades likely are related to differences in niche evolutionary rates. This also suggests that climate plays a strong role in shaping species richness between and within mainland and islands. [ABSTRACT FROM AUTHOR]

Aim (1) To synthesize data on the physical and phylogeographical history of the Mexican highlands, with a focus on the Trans-Mexican Volcanic Belt ( TMVB), and (2) to propose approaches and analyses needed for examining the interaction of climate and volcanism. Location Mexico. Methods We performed a literature and data survey of the climatic, geological and phylogeographical history of the Mexican highlands. We then assessed how the expected effects of topographic isolation, co-occurring palaeoclimatic fluctuations and volcanism can be tested against the distribution of genetic diversity of high-elevation taxa. Results The Mexican highlands present a complex biogeographical, climatic and geological history. Montane taxa have been exposed to a sky-island dynamic through climate fluctuations, allowing for long-term in situ population persistence, while also promoting recent divergence and speciation events. Volcanic activity transformed part of the Mexican highlands during the Pleistocene, mainly in the TMVB, leading to co-occurring climate and topographical changes. The TMVB highlands provide a suitable template to examine how low-latitude mountains can facilitate both the long-term persistence of biodiversity as well as allopatric and parapatric speciation driven by climatic and geological events. Main conclusions Climate fluctuations, together with recent volcanism, have driven the diversification and local persistence of biodiversity within the Mexican highlands. The climate-volcanism interaction is challenging to study; however, this can be overcome by coupling genomic data with landscape analyses that integrate the geological and climatic history of the region. [ABSTRACT FROM AUTHOR]

Aim Using survey data for North American birds, we assess how well historical patterns of species richness are explained by stacked species distribution models and macroecological models. We then describe the degree to which projections of future species richness differ, employing both modelling approaches across multiple emissions scenarios. Location USA and Canada. Methods We use Audubon Christmas Bird Count and North American Breeding Bird Survey data to estimate current and future species richness of birds using two distinct approaches. In the first, we model richness by stacking predictions from individual species distribution models. In the second, we model richness directly, ignoring the contributions of specific taxa to richness estimates. Results The two modelling approaches show similar accuracies when validated with historical observations, particularly winter observations, and result in similar patterns of richness when projected onto current and future climate spaces. Patterns of projected change in species richness differed markedly between winter and summer seasons regardless of modelling approach. Our models suggest that bird species richness in winter will increase or remain stable across much of North America. In contrast, species richness in summer is projected to decrease over much of North America, except part of northern Canada, suggesting that climate may constrain many breeding bird species and communities in the future. Main conclusions Stacked species distribution models and macroecological models produce similar estimates of current and future species richness for each of two seasons despite being built on different concepts of community assembly. Our results suggest that, although the mechanisms that shape geographical variation in biodiversity remain uncertain, these limitations do not impede our ability to predict patterns of species richness at broad scales. Congruence of species richness projections across modelling approaches is encouraging for conservation planning efforts that focus on retaining biodiversity into the future. [ABSTRACT FROM AUTHOR]

Aim East Asia is known for its exceptionally high biological diversity and endemism. Various geological and climatic events during the Pliocene and Pleistocene have been invoked to explain this high endemism, and these processes have had different impacts on different organisms. Herein, we investigate the relative role of these historical processes in the genetic evidence for endemism of intraspecific lineages of two East Asian species: the grey-cheeked fulvetta ( Alcippe morrisonia) and the red-headed tree babbler ( Stachyridopsis ruficeps). Location East Asia. Methods We studied the genetic structure based on mitochondrial and nuclear DNA and evaluated the phylogeographical lineages using coalescent species tree approaches. The influences of different historical processes on diversification among phylogeographical lineages were analysed using coalescent models. We tested correlations between ecological divergence and phylogeographical splits. Results The genetic structure analysis and species tree estimation revealed three deeply divergent lineages within both species. One lineage is endemic to the mountains of Southwest China and the other to Taiwan. Coalescent simulations suggested that lineage diversification mostly occurred during the late Pliocene. Within this time frame, uplift of the mountains of Southwest China and formation of the island of Taiwan are geological events consistent with the geographical isolation and ecological niche divergence of these phylogeographical lineages. Main conclusions Our results suggest that the main driver of avian endemism in East Asia was the formation of new montane and island habitats following the uplift of the mountains of Southwest China and formation of the island of Taiwan in the Pliocene. However, the populations in the two regions were affected differently by the climatic oscillations during the Pleistocene. The mountains of Southwest China were climatically stable during glaciations, allowing populations to persist throughout the Pleistocene and maintain their genetic uniqueness. In contrast, glaciations resulted in lowered sea levels, allowing dispersal between the island of Taiwan and mainland China, thus obscuring the genetic endemism of the Taiwanese populations. [ABSTRACT FROM AUTHOR]

Aim Fungi are drivers of wood decay in forested ecosystem, while bryophytes use dead wood as a platform for their autotrophic lifestyle. We tested the hypothesis that fungal communities on beech logs are mainly structured by substrate quality, while bryophyte communities are structured by climatic gradients. In addition, we tested whether community structure in both organism groups is altered along a gradient from nearly pristine forest to forests heavily affected by management and human disturbance in the past. Location Europe. Methods We surveyed 1207 fallen beech logs in 26 of the best-preserved forest stands across six European countries, representing a gradient in overall naturalness of the forest landscape. Recorded species were classified into ecological guilds. Indirect ordination and variation partitioning was used to analyse the relationship between species composition and environmental variables, recorded at log or site level. Results In total, 10,367 bryophyte and 15,575 fungal records were made, representing 157 and 272 species, respectively. Fungal communities were more clearly structured by substrate quality than were bryophyte communities. In both groups a distinct turnover in species composition was evident along a longitudinal gradient from Central to Western Europe. Fungi specialized in trunk rot and specialized epixylic bryophytes were scarcely represented in Atlantic regions, and partly replaced by species belonging to less specialized guilds. Variables related to climate and forest conditions were confounded along this main geographical gradient in community composition. Main conclusions We found that bryophyte and fungal communities co-occurring on fallen beech logs in European beech forest reserves differed in their responses to biogeographical drivers and local-scale habitat filters. Both groups responded to major gradients in climate and forest conditions, but the loss of specialist guilds in degraded forest landscapes points to a functionally important effect of forest landscape degradation at the European continental scale. [ABSTRACT FROM AUTHOR]

Aim To explore the magnitude and spatial patterns of last glacial stage orbitally forced climatic changes and suborbital climatic fluctuations in southern Africa, and to evaluate their potential roles in determining present biodiversity patterns. Location Africa south of 15° S. Methods Palaeoclimate scenarios for southern Africa were derived for 17 time slices using outputs from HadCM3 atmosphere-ocean general circulation model experiments, including five designed to mimic Heinrich events. Species distribution models for birds of Karoo (45) or Fynbos (31) were used to simulate species' potential past distributions. Species-richness patterns were assessed for each time slice, and minimum species richness for regional endemics of each biome determined for each grid cell. Areas of greatest 'stability' for endemics of each biome were identified using grid cells with greatest minimum richness. Results Simulated suborbital climatic fluctuations were of greater magnitude than orbitally forced changes and had anomalies of opposite sign in many areas. The principal local drivers of suborbital fluctuations were marked contrasts in South Atlantic circulation and temperature between experiments mimicking Heinrich events and those with only slow forcings. These contrasts in ocean circulation and temperature were consistent with marine sediment core evidence of changes in the South Atlantic coincident with Heinrich events in the North Atlantic. Whereas orbitally forced last glacial climates generally resulted in range expansions and increased species richness in many grid cells compared with the present, the contrasting conditions of Heinrich events resulted in much reduced ranges and species richness, especially for Karoo species. Very few grid cells remained suitable for larger numbers of endemic species of either biome under all palaeoclimate scenarios examined, but this minority of 'stable' grid cells correspond to present diversity centres. Main conclusions Suborbital climatic fluctuations during the last glacial stage were probably of considerable magnitude in southern Africa. This may account for apparent inconsistencies between regional palaeoclimate records, as well as being key to determining present biodiversity patterns. [ABSTRACT FROM AUTHOR]

Aim Climate changes in the past had a deep impact on the evolutionary history of many species and left genetic signatures that are often still detectable today. We investigated the geographical pattern of mitochondrial DNA diversity in the European wild boar ( Sus scrofa). Our final aims were to clarify the influence of present and past climatic conditions, infer the geographical position of glacial refugia, and suggest post-glacial spatial dynamics. Location Europe. Methods D-loop sequences were obtained for 763 individuals from Portugal to western Russia. Phylogenetic, multivariate and interpolation methods were used to describe the genetic and geographical patterns. Climatic suitability during the Last Glacial Maximum ( LGM) was predicted using MaxEnt. The effect of present and past suitability on the observed patterns of diversity was evaluated by multiple linear regression. Results We confirmed the existence of a ubiquitous mitochondrial clade in Europe (E1), an endemic clade in Italy (E2) and a few East Asian haplotypes (A), presumably introgressed from domestic pigs. No Near Eastern haplotypes were detected. Genetic divergence was not simply related to geographical distance. A clear south-north decreasing gradient of diversity was observed, with maximum levels in putative glacial refugia. Latitudinal variation in climatic conditions during the LGM was shown to be a good predictor of current genetic diversity. Moreover, an unexpected similarity between Iberia and eastern Europe was observed, while central European populations showed a higher affinity to the Italian gene pool. Main conclusions The current distribution of mitochondrial genetic diversity was highly influenced by past climatic events, especially those related to the LGM, and is consistent with a major contribution of the Italian peninsula and the Balkans to the post-glacial recolonization of northern areas. More recent processes, such as restocking and extensive hunting, probably acted at rather local scales, without great impact on the global pattern of mitochondrial diversity. [ABSTRACT FROM AUTHOR]

Aim The relative importance of long-distance dispersal versus vicariance in determining the distribution of lichen-forming fungi remains unresolved. Here, we examined diversity and distributions in a cosmopolitan lichen-forming fungal species complex, Rhizoplaca melanophthalma sensu lato (Ascomycota), across a broad, intercontinental geographical distribution. We sought to determine the temporal context of diversification and the impacts of past climatic fluctuations on demographic dynamics within this group. Location Antarctica, Asia, Europe, North America and South America. Methods We obtained molecular sequence data from a total of 240 specimens of R. melanophthalma s.l. collected across five continents. We assessed the monophyly of candidate species using individual gene trees and a tree from a seven-locus concatenated data set. Divergence times and relationships among candidate species were evaluated using a multilocus coalescent-based species tree approach. Speciation probabilities were estimated using the coalescent-based species delimitation program bpp. We also calculated statistics on molecular diversity and population demographics for independent lineages. Main conclusions Our analyses of R. melanophthalma s.l. collected from five continents supported the presence of six species-level lineages within this complex. Based on current sampling, two of these lineages were found to have broad intercontinental distributions, while the other four were limited to western North America. Of the six lineages, five were found on a single mountain in the western USA and the sixth occurred no more than 200 km away from this mountain. Our estimates of divergence times suggest that Pleistocene glacial cycles played an important role in species diversification within this group. At least three lineages show evidence of recent or ongoing population expansion. [ABSTRACT FROM AUTHOR]

Aim Understanding patterns of species turnover along environmental gradients and their consistency across taxonomic groups is central to the study of biodiversity. We may expect congruence in diversity patterns across groups whose ranges could be influenced by species interactions. We explore associations between bird and vegetation communities in the tropical Andes to determine whether patterns of species richness and turnover in birds and trees are congruent with elevation, and whether tree species composition, vegetation structure, elevation, or a combination of these best predicts bird species composition. Location A forested 2600-m elevational gradient on the eastern slope of the Peruvian Andes. Methods Bird surveys and vegetation measurements were conducted at 172 points, and a subset of these were spatially matched with fourteen 1-ha tree inventory plots. Diversity patterns were described for trees, birds, and avian foraging guilds. We used dissimilarity matrices to examine patterns of turnover and nestedness. Turnover of birds and trees was examined by comparing compositional change of adjacent plots along the gradient. Multiple regression on distance matrices was employed to determine contributions of tree species composition, vegetation structure and elevation to explaining variation in bird species composition. Results Species richness was higher for trees than for birds, and whereas diversity in both taxa decreased with elevation, tree richness showed a low-elevation plateau before declining at higher elevations. Tree species had narrower distributions compared to birds, but patterns of turnover were largely congruent between taxa. Nestedness contributed much less to dissimilarity than turnover, although birds showed higher nestedness, particularly at high elevations. Tree species composition, elevation and vegetation structure were all important predictors of bird species composition; the best model explained 78% of bird dissimilarity across plots. Tree species composition was always included in the best models, for all birds and foraging guilds. Main conclusions Our assessment of Andean bird and vegetation communities suggests strong correspondence, perhaps due to direct interactions or similar underlying drivers. We hypothesize that with climate change, range shifts in these groups may not occur independently. Rather, birds may have delayed upslope shifts or may be limited to high-elevation patches where appropriate vegetation communities exist. [ABSTRACT FROM AUTHOR]

Aim Our aims were to provide a detailed chronology of past vegetation changes in the tropical mountains of west-central Africa since the Last Glacial Maximum and to discuss montane forest responses to climate change in terms of distribution and biodiversity. Location Lake Bambili, western Cameroon (05°56′ N, 10°14′ E, 2273 m a.s.l.). Methods Fossil pollen was extracted from a long, continuous and well-dated sedimentary sequence extending back 20,000 years. Pollen diversity and evenness estimates were based on rarefaction analysis and on Simpson's (1/ D) index. Results Forest was nearly absent from high elevations during the last glacial period. It expanded gradually from 18.4 cal. kyr bp, interrupted only by reversals coincident with the Heinrich 1 (H1) and Younger Dryas ( YD) climatic events, and then suddenly collapsed at 3.3 cal. kyr bp. This switch from forest to grassland communities occurred within a time span of three centuries. After 3.3 cal. kyr bp only short and taxon-poor forest phases are recorded, specifically between 2.7 and 1 cal. kyr bp and in recent centuries. Main conclusions Our data indicate that the mountain forests of Cameroon are recent, resulting from plant migrations from various sources from 18.4 cal. kyr bp onwards. Their progressive development closely followed intensification of the Atlantic monsoon, leading to the formation of a dense forest between 11.7 and 3.3 cal. kyr bp. The composition of this forest included the co-occurrence of species whose ranges do not overlap today, and indicates the potential for the development of unique iterations of climax forests through time. These forests appear to be very sensitive to Northern Hemisphere climate change, with phases of expansion/contraction coeval with the boreal deglacial signal, including widely recognized events such as H1, the YD and the 8.2 ka event. From 8.2 cal. kyr bp onwards, the progressive opening of the canopy is likely to reflect increased seasonality in rainfall related to more frequent El Niño/Southern Oscillation ( ENSO) events. The final step of this history was the collapse of the montane forest at 3.3 cal. kyr bp. During the last millennium, very severe disruptions have meant that only the most rapidly dispersing species could spread, contributing to a drastic loss of forest biodiversity that has been accentuated by human impact in the last few centuries. [ABSTRACT FROM AUTHOR]

Aim Hypotheses proposed for lineage diversification of tropical montane species have rarely been tested within oceanic islands. Our goal was to understand how basin barriers and Pleistocene climatic fluctuations shaped the distribution of diversity in Eleutherodactylus portoricensis (Eleutherodactylidae), a frog endemic to the montane rain forests of Puerto Rico. Location The north-eastern (Luquillo) and south-eastern (Cayey) mountains of Puerto Rico. Methods We generated mitochondrial DNA (mtDNA) control region sequences ( c. 565 bp) from 144 individuals of E. portoricensis representing 16 localities, and sequenced 646 bp of cytochrome b and 596 bp of nuclear DNA (nDNA) rhodopsin exon and intron 1 from a subset of individuals. We conducted a phylogenetic analysis on the mtDNA sequence data and explored population substructure with maximum parsimony networks, a spatial analysis of molecular variance, and pairwise FST analysis. Coalescent simulations were performed to test alternative models of population divergence in response to late Pleistocene interglacial periods. Historical demography was assessed through coalescent analyses and Bayesian skyline plots. Results We found: (1) two highly divergent groups associated with the disjunct Luquillo and Cayey Mountains, respectively; (2) a shallow mtDNA genetic discontinuity across the La Plata Basin within the Cayey Mountains; (3) phylogeographic congruence between nDNA and mtDNA markers; (4) divergence dates for both mtDNA and nDNA pre-dating the Holocene interglacial ( c. 10 ka), and nDNA suggesting divergence in the penultimate interglacial ( c. 245 ka); and (5) historical demographic stability in both lineages. Main conclusions The low-elevation Caguas Basin is a long-term barrier to gene flow between the two montane frog populations. Measures of genetic diversity for mtDNA were similar in both lineages, but lower nDNA diversity in the Luquillo Mountains lineage suggests infrequent dispersal between the two mountain ranges and colonization by a low-diversity founder population. Population divergence began prior to the Holocene interglacial. Stable population sizes over time indicate a lack of demonstrable demographic response to climatic changes during the last glacial period. This study highlights the importance of topographic complexity in promoting within-island vicariant speciation in the Greater Antilles, and indicates long-term persistence and lineage diversification despite late Pleistocene climatic oscillations. [ABSTRACT FROM AUTHOR]

Aim Parrots are thought to have originated on Gondwana during the Cretaceous. The initial split within crown group parrots separated the New Zealand taxa from the remaining extant species and was considered to coincide with the separation of New Zealand from Gondwana 82-85 Ma, assuming that the diversification of parrots was mainly shaped by vicariance. However, the distribution patterns of several extant parrot groups cannot be explained without invoking transoceanic dispersal, challenging this assumption. Here, we present a temporal and spatial framework for the diversification of parrots using external avian fossils as calibration points in order to evaluate the relative importance of the influences of past climate change, plate tectonics and ecological opportunity. Location Australasian, African, Indo-Malayan and Neotropical regions. Methods Phylogenetic relationships were investigated using partial sequences of the nuclear genes c-mos, RAG-1 and Zenk of 75 parrot and 21 other avian taxa. Divergence dates and confidence intervals were estimated using a Bayesian relaxed molecular clock approach. Biogeographic patterns were evaluated taking temporal connectivity between areas into account. We tested whether diversification remained constant over time and if some parrot groups were more species-rich than expected given their age. Results Crown group diversification of parrots started only about 58 Ma, in the Palaeogene, significantly later than previously thought. The Australasian lories and possibly also the Neotropical Arini were found to be unexpectedly species-rich. Diversification rates probably increased around the Eocene/Oligocene boundary and in the middle Miocene, during two periods of major global climatic aberrations characterized by global cooling. Main conclusions The diversification of parrots was shaped by climatic and geological events as well as by key innovations. Initial vicariance events caused by continental break-up were followed by transoceanic dispersal and local radiations. Habitat shifts caused by climate change and mountain orogenesis may have acted as a catalyst to the diversification by providing new ecological opportunities and challenges as well as by causing isolation as a result of habitat fragmentation. The lories constitute the only highly nectarivorous parrot clade, and their diet shift, associated with morphological innovation, may have acted as an evolutionary key innovation, allowing them to explore underutilized niches and promoting their diversification. [ABSTRACT FROM AUTHOR]

Aim To investigate the chronology, causes and consequences of the extinction of the autochthonous Pleistocene small mammals of Mallorca. Location Mallorca (Gymnesic Islands, Balearics, Western Mediterranean). Methods We have obtained the first direct 14C ages from the bone collagen of selected samples of two extinct endemic small mammals from Mallorca: the Balearic dormouse, Eliomys morpheus (Rodentia: Myoxidae) and the Balearic shrew, Asoriculus hidalgoi (Soricomorpha: Soricidae). We also present evidence for the absence of both endemics from the earliest Mallorcan archaeological sites and for the introduction of the garden dormouse, Eliomys quercinus, and the wood mouse, Apodemus sylvaticus. Combined information from direct dating of bone collagen of E. quercinus and A. sylvaticus and from cultural associations provides an adequate framework to establish the chronology of the faunal change and to compare it with the chronological information available on climatic change and the first arrival of humans on the islands. Results The chronological record includes the latest evidence available for the survival of endemic species and the earliest introduction of small mammals into Mallorca. We present ‘uncertainty periods for extinction’ (UPEs) of both endemic mammals based on the chronology of their last occurrence and on the inferred timing of their extinction (restricted UPEs). Main conclusions Possible causes for the extinction of autochthonous small mammals on Mallorca are discussed. Once we have discarded climatic causes, predation by invasive species, competition with newcomers and habitat deterioration, the introduction of diseases emerges as the most reasonable explanation for these extinctions. Based on the identification of changes in keystone species in Mallorcan ecosystems, we propose a tentative schedule of key ecological changes that have taken place over the past 5 millennia. [ABSTRACT FROM AUTHOR]

Aim To unravel the reasons why a group of islands of 800 km2 area should support over 200 extant land snail species. Location The temperate Atlantic Madeiran archipelago. Methods Distributional surveys and model testing. Results Repeated volcanic events have changed the topography of the islands and created periodic further isolates. There has been climatic fluctuation and varying sea level. Individual locations are not species-rich, but there is replacement from one subregion to another. Evidence of competitive interactions is lacking. Main conclusions High diversity results from the fortuitous coincidence of rates of geological and climatic change and isolation on the one hand, and migration and genetic divergence on the other. Hubbell’s neutral model of biodiversity explains species richness if a factor is added describing structural instability or periodicity, here called the geodetic rate. This geodetic, biological interaction can explain why some archipelagos are species-rich. [ABSTRACT FROM AUTHOR]

Aims Insular Southeast Asia and adjacent regions are geographically complex, and were dramatically affected by both Pliocene and Pleistocene changes in climate, sea level and geology. These circumstances allow the testing of several biogeographical hypotheses regarding species distribution patterns and phylogeny. Avian species in this area present a challenge to biogeographers, as many are less hindered by barriers that may block the movements of other species. Widely distributed Southeast Asian avian lineages, of which there are many, have been generally neglected. Ficedula flycatchers are distributed across Eurasia, but are most diverse within southern Asia and Southeast Asian and Indo-Australian islands. We tested the roles of vicariance, dispersal and the evolution of migratory behaviours as mechanisms of speciation within the Ficedula flycatchers, with a focus on species distributed in insular Southeast Asia. Methods Using a published molecular phylogeny of Ficedula flycatchers, we reconstructed ancestral geographical areas using dispersal vicariance analysis, weighted ancestral area analysis, and a maximum likelihood method. We evaluated the evolution of migratory behaviours using maximum likelihood ancestral character state reconstruction. Speciation timing estimates were calculated via local molecular clock methods. Results Ficedula originated in southern mainland Asia, c. 6.5 Ma. Our analyses indicate that two lineages within Ficedula independently and contemporaneously colonized insular Southeast Asia and Indo-Australia, c. 5 Ma. The potential impact of vicariance due to rising sea levels is difficult to assess in these early colonization events because the ancestral areas to these clades are reconstructed as oceanic islands. Within each of these clades, inter-island dispersal was critical to species’ diversification across oceanic and continental islands. Furthermore, Pliocene and Pleistocene climatic change may have caused the disjunct island distributions between several pairs of sister taxa. Both vicariance and dispersal shaped the distributions of continental species. Main conclusions This study presents the first evaluation, for Ficedula, of the importance of vicariance and dispersal in shaping distributions, particularly across insular Southeast Asia and Indo-Australia. Although vicariant speciation may have initially separated the island clades from mainland ancestors, speciation within these clades was driven primarily by dispersal. Our results contribute to the emerging body of literature concluding that dynamic geological processes and climatic change throughout the Pliocene and Pleistocene have been important factors in faunal diversification across continental and oceanic islands. [ABSTRACT FROM AUTHOR]

Biogeography is a vibrant academic discipline that plays an important role in framing and directing debates on some of the most important environmental issues of our time, such as the impacts of climate change on biodiversity, biotic homogenization and the effectiveness of global conservation policy. Despite this, biogeography suffers from a low public profile and may consequently be poorly understood by the public. Here I review the representation of the term biogeography, and a selection of biogeographers in the public sphere (newspapers, websites, blogs) and the academic sphere (journals and reports) to understand more fully the public perception of the discipline. As anticipated, the survey suggests that the term ‘biogeography’ has little public currency, and that the public still largely associate the subject area with either eminent Victorians such as A.R. Wallace or modern greats such as E.O. Wilson. I conclude by discussing the potential consequences of the virtual absence of biogeography from public discourse for education and professional biogeographers. [ABSTRACT FROM AUTHOR]

Aim To explain the relationship between topography, prevailing winds and precipitation in order to identify regions with contrasting precipitation regimes and then compare floristic similarity among regions in the context of climate change. Location Eastern slope of the tropical Andes, South America. Methods We used information sources in the public domain to identify the relationship between geology, topography, prevailing wind patterns and precipitation. Areas with contrasting precipitation regimes were identified and compared for their floristic similarity. Results We identify spatially separate super-humid, humid and relatively dry regions on the eastern slope of the Andes and show how they are formed by the interaction of prevailing winds, diurnally varying atmospheric circulations and the local topography of the Andes. One key aspect related to the formation of these climatically distinct regions is the South American low-level jet (SALLJ), a relatively steady wind gyre that flows pole-ward along the eastern slopes of the Andes and is part of the gyre associated with the Atlantic trade winds that cross the Amazon Basin. The strongest winds of the SALLJ occur near the ‘elbow of the Andes’ at 18° S. Super-humid regions with mean annual precipitation greater than 3500 mm, are associated with a ‘favourable’ combination of topography, wind-flow orientation and local air circulation that favours ascent at certain hours of the day. Much drier regions, with mean annual precipitation less than 1500 mm, are associated with ‘unfavourable’ topographic orientation with respect to the mean winds and areas of reduced cloudiness produced by local breezes that moderate the cloudiness. We show the distribution of satellite-estimated frequency of cloudiness and offer hypotheses to explain the occurrence of these patterns and to explain regions of anomalously low precipitation in Bolivia and northern Peru. Floristic analysis shows that overall similarity among all circumscribed regions of this study is low; however, similarity among super-humid and humid regions is greater when compared with similarity among dry regions. Spatially separate areas with humid and super-humid precipitation regimes show similarity gradients that are correlated with latitude (proximity) and precipitation. Main conclusions The distribution of precipitation on the eastern slope of the Andes is not simply correlated with latitude, as is often assumed, but is the result of the interplay between wind and topography. Understanding the phenomena responsible for producing the observed precipitation patterns is important for mapping and modelling biodiversity, as well as for interpreting both past and future climate scenarios and the impact of climate change on biodiversity. Super-humid and dry regions have topographic characteristics that contribute to local climatic stability and may represent ancestral refugia for biodiversity; these regions are a conservation priority due to their unique climatic characteristics and the biodiversity associated with those characteristics. [ABSTRACT FROM AUTHOR]

Aim To investigate the influence of Holocene climatic and human-induced changes on a region of high biodiversity in southern Peruvian Amazonia. Location Four palaeoecological records from separate lakes within a lake district close to the modern city of Puerto Maldonado, Peru. Results The lakes provide a palaeoecological record spanning the last 8200 years. A mid-Holocene dry event is documented in all of the records that extend back > 6000 years. The dry event appears to have lasted from c. 7200 yrbp until c. 3300 yrbp. The onset of wetter conditions coincides with the formation of the youngest of the four lakes. The earliest occupation of these sites is inferred from the presence of charcoal at 7200 yrbp, and the first crop pollen is found at 3630 yrbp. Lakes that were regularly occupied were colonized soon after they formed. A reduction in charcoal concentration and the absence of crop pollen after c. 500 bp in all lakes is consistent with site abandonment following conquest. Main conclusions The mid-Holocene dry event is suggested to be part of a time-transgressive drying that tracked from north to south in both the Andes and the Amazon lowlands. The last millennium may represent the period of highest sustained lake levels within the Holocene. The proximity of the four lakes allows a landscape-scale analysis of the spatial extent of human disturbance centred on a known site of human occupation and reveals the highly localized nature of pre-Columbian anthropogenic disturbance in Amazonian landscapes. Inferences regarding widespread pre-Columbian landscape modification by indigenous peoples must take into account key site attributes, such as seasonality and proximity to rivers. [ABSTRACT FROM AUTHOR]

Aim To analyse the current geographical structure of chloroplast DNA variation in the Turnera sidoides L. complex in order to establish historical biogeographical hypotheses for the mid-latitude South American lowlands. During the Quaternary, the climate shifted from tropical humid to cold dry, and the vegetation cover has not been stable. The consequences of these processes on the current distribution of the vegetation of this area have received very little attention. Location The mid-latitude South American lowlands extend between c. 20 and 40°S and include Uruguay, northern, central and eastern Argentina, southern Brazil, and parts of southern Paraguay and Bolivia. They are surrounded by higher-elevation systems. Methods Turnera sidoides is a well-studied polyploid complex of perennial rhizomatous herbs occurring throughout the area of interest. We analysed 321 individuals from 79 populations of the five recognized subspecies. We also included progenies from artificial crosses in order to analyse chloroplast inheritance. After screening sequences for four non-coding chloroplast DNA regions, the trnL– trnF spacer was selected to characterize the collection. Results Three haplotypes can be easily identified, with each differing from the others in two independent characters. A clear geographic structure is revealed when haplotypes are plotted for the complex as a whole regardless of subspecies and cytotype. Three distinct regions can be identified. Main conclusions We propose three putative refugial areas for the Turnera sidoides complex, which are associated with the orographical systems of the region. Ravines and slopes in the Haedo Cuchilla system in northern Uruguay, the elevations of the western side of the area in Argentina, and the eastern Serranías system in south-eastern Uruguay may each have served as refugia in which the A, B and C haplotypes became fixed during the drier climatic phases. Biogeographical patterns in the area covered by T. sidoides, particularly east of the Uruguay River, have not previously been analysed from a historical perspective. [ABSTRACT FROM AUTHOR]

Aim Many attempts to predict the potential range of species rely on environmental niche (or 'bioclimate envelope') modelling, yet the effects of using different niche-based methodologies require further investigation. Here we investigate the impact that the choice of model can have on predictions, identify key reasons why model output may differ and discuss the implications that model uncertainty has for policy-guiding applications. Location The Western Cape of South Africa. Methods We applied nine of the most widely used modelling techniques to model potential distributions under current and predicted future climate for four species (including two subspecies) of Proteaceae. Each model was built using an identical set of five input variables and distribution data for 3996 sampled sites. We compare model predictions by testing agreement between observed and simulated distributions for the present day (using the area under the receiver operating characteristic curve (AUC) and kappa statistics) and by assessing consistency in predictions of range size changes under future climate (using cluster analysis). Results Our analyses show significant differences between predictions from different models, with predicted changes in range size by 2030 differing in both magnitude and direction (e.g. from 92% loss to 322% gain). We explain differences with reference to two characteristics of the modelling techniques: data input requirements (presence/absence vs. presence-only approaches) and assumptions made by each algorithm when extrapolating beyond the range of data used to build the model. The effects of these factors should be carefully considered when using this modelling approach to predict species ranges. Main conclusions We highlight an important source of uncertainty in assessments of the impacts of climate change on biodiversity and emphasize that model predictions should be interpreted in policy-guiding applications along with a full appreciation of uncertainty. [ABSTRACT FROM AUTHOR]

Aim To assess the geographical transferability of niche-based species distribution models fitted with two modelling techniques. Location Two distinct geographical study areas in Switzerland and Austria, in the subalpine and alpine belts. Methods Generalized linear and generalized additive models (GLM and GAM) with a binomial probability distribution and a logit link were fitted for 54 plant species, based on topoclimatic predictor variables. These models were then evaluated quantitatively and used for spatially explicit predictions within (internal evaluation and prediction) and between (external evaluation and prediction) the two regions. Comparisons of evaluations and spatial predictions between regions and models were conducted in order to test if species and methods meet the criteria of full transferability. By full transferability, we mean that: (1) the internal evaluation of models fitted in region A and B must be similar; (2) a model fitted in region A must at least retain a comparable external evaluation when projected into region B, and vice-versa; and (3) internal and external spatial predictions have to match within both regions. Results The measures of model fit are, on average, 24% higher for GAMs than for GLMs in both regions. However, the differences between internal and external evaluations (AUC coefficient) are also higher for GAMs than for GLMs (a difference of 30% for models fitted in Switzerland and 54% for models fitted in Austria). Transferability, as measured with the AUC evaluation, fails for 68% of the species in Switzerland and 55% in Austria for GLMs (respectively for 67% and 53% of the species for GAMs). For both GAMs and GLMs, the agreement between internal and external predictions is rather weak on average (Kulczynski's coefficient in the range 0.3-0.4), but varies widely among individual species. The dominant pattern is an asymmetrical transferability between the two study regions (a mean decrease of 20% for the AUC coefficient when the models are transferred from Switzerland and 13% when they are transferred from Austria). Main conclusions The large inter-specific variability observed among the 54 study species underlines the need to consider more than a few species to test properly the transferability of species distribution models. The pronounced asymmetry in transferability between the two study regions may be due to peculiarities of these regions, such as differences in the ranges of environmental predictors or the varied impact of land-use history, or to species-specific reasons like differential phenotypic plasticity, existence of ecotypes or varied dependence on biotic interactions that are not properly incorporated into niche-based models. The lower variation between internal and external evaluation of GLMs compared to GAMs further suggests that overfitting may reduce transferability. Overall, a limited geographical transferability calls for caution when projecting niche-based models for assessing the fate of species in future environments. [ABSTRACT FROM AUTHOR]

Aim We explore the relationship between current European distributions of amphibian and reptile species and observed climate, and project species potential distributions into the future. Potential impacts of climate warming are assessed by quantifying the magnitude and direction of modelled distributional shifts for every species. In particular we ask, first, what proportion of amphibian and reptile species are projected to lose and gain suitable climate space in the future? Secondly, do species projections vary according to taxonomic, spatial or environmental properties? And thirdly, what climate factors might be driving projections of loss or gain in suitable environments for species? Location Europe. Methods Distributions of species are modelled with four species—climate envelope techniques (artificial neural networks, generalized linear models, generalized additive models, and classification tree analyses) and distributions are projected into the future using five climate-change scenarios for 2050. Future projections are made considering two extreme assumptions: species have unlimited dispersal ability and species have no dispersal ability. A novel hybrid approach for combining ensembles of forecasts is then used to group linearly covarying projections into clusters with reduced inter-model variability. Results We show that a great proportion of amphibian and reptile species are projected to expand distributions if dispersal is unlimited. This is because warming in the cooler northern ranges of species creates new opportunities for colonization. If species are unable to disperse, then most species are projected to lose range. Loss of suitable climate space for species is projected to occur mainly in the south-west of Europe, including the Iberian Peninsula, whilst species in the south-east are projected to gain suitable climate. This is because dry conditions in the south-west are projected to increase, approaching the levels found in North Africa, where few amphibian species are able to persist. Main conclusions The impact of increasing temperatures on amphibian and reptile species may be less deleterious than previously postulated; indeed, climate cooling would be more deleterious for the persistence of amphibian and reptile species than warming. The ability of species to cope with climate warming may, however, be offset by projected decreases in the availability of water. This should be particularly true for amphibians. Limited dispersal ability may further increase the vulnerability of amphibians and reptiles to changes in climate. [ABSTRACT FROM AUTHOR]

Aim To provide a test of the conservatism of a species' niche over the last 20,000 years by tracking the distribution of eight pollen taxa relative to climate type as they migrated across eastern North America following the Last Glacial Maximum (LGM). Location North America. Methods We drew taxon occurrence data from the North American pollen records in the Global Pollen Database, representing eight pollen types — all taxa for which ≥5 distinct geographic occurrences were available in both the present day and at the LGM (21,000 years ago ± 3000 years). These data were incorporated into ecological niche models based on present-day and LGM climatological summaries available from the Palaeoclimate Modelling Intercomparison Project to produce predicted potential geographic distributions for each species at present and at the LGM. The output for each time period was projected onto the 'other' time period, and tested using independent known occurrence information from that period. Results The result of our analyses was that all species tested showed general conservatism in ecological characteristics over the climate changes associated with the Pleistocene-to-Recent transition. Main conclusions This analysis constitutes a further demonstration of general and pervasive conservatism in ecological niche characteristics over moderate periods of time despite profound changes in climate and environmental conditions. As such, our results reinforce the application of ecological niche modelling techniques to the reconstruction of Pleistocene biodiversity distribution patterns, and to project the future potential distribution range of species in the face of global-scale climatic changes. [ABSTRACT FROM AUTHOR]

Aim To analyse the conservation status of tropical dry forests at the global scale, by combining a newly developed global distribution map with spatial data describing different threats, and to identify the relative exposure of different forest areas to such threats. Location Global assessment. Methods We present a new global distribution map of tropical dry forest derived from the recently developed MODIS Vegetation Continuous Fields (VCF) product, which depicts percentage tree cover at a resolution of 500 m, combined with previously defined maps of biomes. This distribution map was overlaid with spatial data to estimate the exposure of tropical dry forests to a number of different threats: climate change, habitat fragmentation, fire, human population density and conversion to cropland. The extent of tropical dry forest currently protected was estimated by overlaying the forest map with a global data set of the distribution of protected areas. Results It is estimated that 1,048,700 km2 of tropical dry forest remains, distributed throughout the three tropical regions. More than half of the forest area (54.2%) is located within South America, the remaining area being almost equally divided between North and Central America, Africa and Eurasia, with a relatively small proportion (3.8%) occurring within Australasia and Southeast Asia. Overall, c. 97% of the remaining area of tropical dry forest is at risk from one or more of the threats considered, with highest percentages recorded for Eurasia. The relative exposure to different threats differed between regions: while climate change is relatively significant in the Americas, habitat fragmentation and fire affect a higher proportion of African forests, whereas agricultural conversion and human population density are most influential in Eurasia. Evidence suggests that c. 300,000 km2 of tropical dry forest now coincide with some form of protected area, with 71.8% of this total being located within South America. Main conclusions Virtually all of the tropical dry forests that remain are currently exposed to a variety of different threats, largely resulting from human activity. Taking their high biodiversity value into consideration, this indicates that tropical dry forests should be accorded high conservation priority. The results presented here could be used to identify which forest areas should be accorded highest priority for conservation action. In particular, the expansion of the global protected area network, particularly in Mesoamerica, should be given urgent consideration. [ABSTRACT FROM AUTHOR]

This study proposes a process to select plant species that would provide suitable candidates for monitoring climate change impacts in areas where complete biological inventories are lacking. Inselberg floras of nine inselberg landscapes (i.e. isolated mountains) in the arid Desert and Nama Karoo biome in Namibia were analysed to develop a selection process. Data from detailed field surveys were summarized to determine species only occurring on inselberg habitats (i.e. inselberg specialists). Detrended correspondence analysis and a step-by-step selection process based on species distribution patterns were used to determine species occurring on inselbergs beyond their zonal distribution ranges. The systematic selection process initially identified 88 plant species. Based on field observations and published sources eliminating species (1) with a wide distribution elsewhere, (2) distribution influenced by local effects and (3) for which their status of knowledge of distribution was clearly inadequate, this list was further reduced to 25 species. This included southern species occurring on inselbergs likely beyond their zonal distribution, such as Adenolobus garipensis, Aloe dichotoma and Euphorbia gummifera, as well as savanna and escarpment species at their western zonal distribution edge (e.g. Cordia sinensis, Commiphora glaucescens and Moringa ovalifolia). The step-by-step selection process proposed in this study to assist with the selection of indicators for climate change provides an objective tool in areas where biodiversity coverage is not adequate and little is known about physiology, growth and reproductive patterns of individual species. As such it introduces a method for preliminary screening of species, but will require further input based on field observations and expert knowledge. [ABSTRACT FROM AUTHOR]

Aim Greenhouse-induced warming and resulting shifts in climatic zones may exceed the migration capabilities of some species. We used fourteen combinations of General Circulation Models (GCMs) and Global Vegetation Models (GVMs) to investigate possible migration rates required under CO2 -doubled climatic forcing. Location Global. Methods Migration distances were calculated between grid cells of future biome type x and nearest same-biome-type cells in the current climate. In `base-case' calculations, we assumed that 2 × CO2 climate forcing would occur in 100 years, we used ten biome types and we measured migration distances as straight-line distances ignoring water barriers and human development. In sensitivity analyses, we investigated different time periods of 2 × CO2 climate forcing, more narrowly defined biomes and barriers because of water bodies and human development. Results In the base-case calculations, average migration rates varied significantly according to the GVM used (BIOME3 vs. MAPSS), the age of the GCM (older- vs. newer-generation GCMs), and whether or not GCMs included sulphate cooling or CO2 fertilization effects. However, high migration rates (≥ 1000 m year-1 ) were relatively common in all models, consisting on average of 17% grid cells for BIOME3 and 21% for MAPSS. Migration rates were much higher in boreal and temperate biomes than in tropical biomes. Doubling of the time period of 2 × CO2 forcing reduced these areas of high migration rates to c . 12% of grid cells for both BIOME3 and MAPSS. However, to obtain migration rates in the Boreal biome that were similar in magnitude to those observed for spruce when it followed the retreating North American Glacier, a radical increase in the period of warming was required, from 100 to >1000 years. A reduction in biome area by an order of magnitude increased migration rates by one to three orders of magnitude,... [ABSTRACT FROM AUTHOR]

Aim Spatial models generated in a geographical information system (GIS) are utilized to predict shifts in the distribution and diversity of tropical forests in Costa Rica in response to climate change. Location Analyses were conducted using the Holdridge life zone classification system for the Central American country of Costa Rica. Methods Mean annual precipitation and temperature ranges were varied to reflect different magnitudes of climate change and then used to predict the distributions of nineteen forest types (life zones). Holdridge et al .'s (1971) field survey data of species richness and endemism for ten Costa Rican life zones were also analysed and considered in view of the climate change scenarios. Results The scenarios indicated that shifts in the distribution of tropical forest life zones are likely to occur as a result of climatic changes. High elevation life zones were shown to be more sensitive to changes in temperature, while lower elevation life zones tended to be more sensitive to changes in precipitation. Regional life zone diversity was greatly reduced in an extreme wet and warm climate scenario. Three elevation-associated life zones (lower montane rain forest, montane rain forest, and premontane rain forest) ranked in the top four in percentage number of endemic species. The lowland seasonally dry forest life zone ranked second in this group, suggesting that this life zone has a unique species composition in comparison with other lowland Holdridge life zones. Of the nineteen life zones, these four life zones displayed particular sensitivity to the climate changes modelled here. Main conclusions Elevation-associated life zones may be particularly vulnerable to future climatic changes. This is also true of lowland seasonally dry forest. Geographical regions in Costa Rica that contain these life zones are likely to warrant special management and conservation attention in the event of predicted climate change. [ABSTRACT FROM AUTHOR]