Update: From acorns mighty micropockets grow

Changes in climate, land use, fire incidence, and ecological connections all may contribute to current species' range shifts. Species shift range individually, and not all species shift range at the same time and rate. This variation causes community reorganization in both the old and new ranges. In terrestrial ecosystems, range shifts alter aboveground-belowground interactions, influencing species abundance, community composition, ecosystem processes and services, and feedbacks within communities and ecosystems. Thus, range shifts may result in no-analog communities where foundation species and community genetics play unprecedented roles, possibly leading to novel ecosystems. Long-distance dispersal can enhance the disruption of aboveground-belowground interactions of plants, herbivores, pathogens, symbiotic mutualists, and decomposer organisms. These effects are most likely stronger for latitudinal than for altitudinal range shifts. Disrupted aboveground-belowground interactions may have influenced historical postglacial range shifts as well. Assisted migration without considering aboveground-belowground interactions could enhance risks of such range shift–induced invasions.

Migration is a fundamental biological phenomenon with significant impacts on the survival of populations and ecosystems. Its precise definition depends on the ecological discipline in focus, but it essentially entails the movement of an individual or population between habitats to ensure survival and enhance the likelihood of successful reproduction. Evolution has led to different types and mechanisms of migration ranging from passive to active movements, and from a few meter to migrations across biomes. Climate change has a strong effect on migration behaviour, leading to shifts in the ranges of populations and species as the quality and availability of habitats are altered. This chapter provides an overview of migratory behaviour and points out examples of variations caused by climate change. In addition, it discusses the context of migratory and ecological connectivity, both of which are essential for preserving biodiversity and facilitating adaptation. Understanding migration, range shifts, and dispersal is key to effective conservation and management efforts and should therefore be a primary focus of international collaborations.

The way in which climate change is experienced by species will be highly variable, due both to the spatial and temporal heterogeneity of climate change as well as differences in species’ sensitivity to such changes. While previous methods for addressing variation in climate exposure have considered metrics of climate change speed or direction (e.g., climate velocity), these metrics do not account for historical climate variability. Species have evolved to accommodate historical variability in climate, and we expect range shifts to be more likely in areas where anthropogenic climate change exceeds the bounds of unforced climate variability. We assessed the historical relationship between climatic variability, the strength of the anthropogenic climate change signal, and observed terrestrial latitudinal species range shifts. We accounted for directional change in climate variables (signal) relative to natural variability (noise) using signal to noise ratios (SNR) for ecologically relevant temperature metrics and used linear regression to understand the relationship between SNR and observed species range shifts. We also looked at projected mid-century SNRs calculated from a large ensemble Global Climate Model to identify places where strong SNRs may emerge and where we may therefore anticipate significant range shifts. We found that as the climate becomes increasingly different from historical climate averages (i.e., as SNR increases) species shift faster on latitudinal leading edges. This is true independent of the magnitude of temperature change. The effects of SNR are more variable on trailing edges and within species ranges. Most range shift studies to date have taken place in North America and Europe, which are not the places that have experienced the highest SNR. While SNR is projected to increase globally by mid-century, increases will be highest in tropical areas. These areas might therefore be hotspots of future range shifts. It is important to consider historical variability experienced by the species in addition to absolute temperature change, especially for latitudinal leading edges. We discuss implications for studying future range shifts and range shift management.

With the advent of molecular data, and particularly the use of molecular clocks when warranted, biogeographers have begun to reexamine the roles of Gondwana breakup, immigration from the Laurasian tropics, and transoceanic dispersal in shaping similarities among the world’s tropical floras (Givnish et al. 1999, 2000; Lavin et al. 2000, 2005; Renner et al. 2000, 2001; Azuma et al. 2001; Chanderbali et al. 2001; Renner and Meyer 2001; Conti et al. 2002; Davis et al. 2002; Jobson et al. 2003; Zhang and Renner 2003; Berry et al. 2004). As increasing numbers of continental disjunctions are analyzed, it has also become possible to ask whether there are regular patterns in the directions and timing of transoceanic dispersal events (S. S. Renner, in this issue). Wind and ocean surface currents (as well as tectonics) all affect dispersal and are not randomly distributed in space and time; they should thus leave an evolutionary trace provided that they have been stable long enough to override lineage-specific differences in dispersal and establishment capability (e.g., see Munoz et al. 2004). Tropical intercontinental disjunctions raise issues analogous to those involving disjunct temperate floras in the Northern Hemisphere (see IJPS symposium edited by Manos and Donoghue [2001]), but the ocean gulfs are often greater and the latitudinal distributions of taxa less dynamic. Similar issues also emerge in studying the origin of island lineages (Wagner and Funk 1995; Givnish 1998; Emerson 2002). Insular groups pose special problems, especially when extraordinary divergence due to adaptive radiation makes it difficult to identify mainland ancestors or relatives. Yet intercontinental disjunctions can be even more complex to decipher, given the frequent lack of asymmetries between potential source and target areas (but see T. J. Givnish et al.; K. J. Sytsma et al.), the existence of direct connections to other landmasses at various times, and the longer and more complex tectonic histories of the terrains. The papers collected here represent the product of a symposium held in Madison during August 2002, sponsored by the Association for Tropical Biology and the Association for Systematic Botany and honoring Robert Thorne for his outstanding contributions to biogeography and especially to the analysis of tropical plant disjunctions (Thorne 1972, 1973; R. Thorne’s ‘‘reflections’’ at the end of this volume provide an entry into his biogeographic contributions). We invited researchers to present analyses based on molecular data for a variety of disjunctly distributed tropical lineages that, in aggregate, display a diversity of continental disjunctions, mechanisms of dispersal, and geological age. We asked each contributor to address three questions: (1) How much information about the timing and nature of the events causing disjunctions can be obtained from molecular data? (2) What appear to be the relative roles of dispersal and vicariance, and how do these relate to events in Earth history? and (3) How can we cross-check and validate our inferences using fossils or other data? All of the contributions calibrate the lengths of branches in molecular trees (measured as the numbers of inferred nucleotide substitutions) against the apparent age of one or more ancestral taxa (inferred from the geological age of the oldest known fossil attributed to those taxa). The absolute dates of cladogenetic events within a lineage are then inferred using one or more of several calibration models and attributed to apparent dispersal or vicariance events, which have themselves been inferred from the distributions of modern-day taxa and their phylogenetic relationships to each other. The timing of range expansions is finally tied to shifts in geography, climate, or likely pathways for dispersal during geological time, and conclusions are drawn about the likely mechanisms underlying a particular disjunct distribution. The validity of such conclusions thus hinges on the completeness of our knowledge of the fossil record, both in areal extent and in time; on uncertainties in the branch lengths inferred from particular molecular markers; on the validity of chronological calibrations based on particular models and a particular set of fossil dates; and on uncertainties regarding the distributions of ancestral taxa inferred from a molecular phylogeny, distributions of modern-day taxa, and particular models for shifts in geographic range. Nevertheless, the approaches taken by papers in this symposium, involving the complementary use of molecular and paleobotanical data, offer some of the most powerful techniques now available for assessing the age—and, hence, the mechanism—associated with a shift in the range of a lineage. Without such approaches, or comprehensive and thus perhaps unattainable fossil data bearing on the timing of a range shift, one might indiscriminately invoke long-distance dispersal, continental drift, or boreotropical migration to explain essentially any tropical disjunction. The surprising conclusion from careful analyses in this symposium and elsewhere (e.g., Cronn and Wendel 2004; Lavin et al. 2005) is that long-distance dispersal may be more pervasive than all but its most ardent advocates (e.g., Iltis 1967) had previously proposed.

Climate change has emerged as a dominant driver of global biodiversity loss, profoundly altering zoological diversity, species distribution, and ecosystem functioning. Rising temperatures, erratic precipitation, ocean acidification, and habitat fragmentation disrupt physiological processes, migration patterns, and trophic interactions across taxa. This review explores the impact of climate change on zoological diversity and species distribution. Terrestrial, aquatic, and marine ecosystems exhibit varying degrees of vulnerability, with endemic and specialised species facing heightened extinction risks. Polar fauna such as seals and polar bears, tropical primates, coral reef communities, and migratory birds demonstrate clear evidence of climate-induced population decline and range shifts. Evolutionary responses, including genetic adaptation and phenotypic plasticity, are observed in some taxa but remain insufficient to counter rapid environmental changes. Advances in remote sensing, GIS-based species modelling, and molecular techniques such as genomics and environmental DNA (eDNA) have enhanced understanding of climate impacts and enabled predictive biodiversity mapping. Conservation measures encompassing ecosystem-based adaptation, habitat restoration, captive breeding, and wildlife corridor establishment contribute to mitigating biodiversity loss. Policy frameworks under the Convention on Biological Diversity (CBD), IUCN, and IPCC emphasise integrating nature-based solutions with national climate strategies. Despite significant progress, uncertainties in predictive models, data scarcity, and limited integration between ecological and socio-economic systems impede effective conservation planning. Future research must prioritise long-term ecological monitoring, multi-scale data synthesis, and cross-sectoral policy implementation to enhance resilience. Integrating indigenous ecological knowledge with scientific innovations will strengthen adaptation measures and ensure sustainable biodiversity management in the face of accelerating climatic shifts.

TThe tropical montane cloud forests of the Andes harbor an exceptional species diversity and endemism, which is currently under threat from rapid environmental change. Understanding the patterns and processes behind this diversity is a major challenge. In this chapter, we provide a conceptual synthesis of the driving factors behind the processes that underpin the evolution of species diversity in the montane forest of the Andes. Species richness and endemism are attributed to a mixture of historical, evolutionary, and ecological processes. Some classical hypotheses highlight the relationship between species diversity and spatial structure of the Andean mountains. In contrast, others have focused on the role of physical barriers that arose during the late Eocene and Neogene (uplift of the Andes) and the range shifts caused by climatic and environmental dynamics during the Quaternary period that resulted in a combination of vicariance and dispersal events. Moreover, species tolerances to environmental conditions (especially temperature) can affect species dispersal and facilitate allopatric isolation. However, the role of intrinsic traits and life-history strategies as a driver of Andean diversity is sometimes unclear.

Species respond dynamically to climate change and exhibit time lags. Consequently, species may not occupy their full climatic niche during range shifting. Here, we assessed climate niche tracking during recent range shifts of European and UnitedStates (US) birds. Using data from two European bird atlases and from the North American Breeding Bird Survey betweenthe 1980s and 2010s, we analysed range overlap and climate niche overlap based on kernel density estimation. Phylogenetic multiple regression was used to assess the effect of species morphological, ecological and biogeographic traits on range and niche metrics. European birds shifted their ranges north and north-eastwards, US birds westwards. Range unfilling was lower than expected by null models, and niche expansion was more common than niche unfilling. Also, climate niche tracking was generally lower in US birds and poorly explained by species traits. Overall, our results suggest that dispersal limitations were minor in range shifting birds in Europe and theUSA while delayed extinctions from unfavourable areas seem more important. Regional differences could be related to differences in land use history and monitoring schemes. Comparative analyses of range and niche shifts provide a useful screening approach for identifying the importance of transient dynamics and time-lagged responses to climate change. This article is part of the theme issue 'Ecological novelty and planetary stewardship: biodiversity dynamics in a transforming biosphere'.

A growing body of literature seeks to explain variation in range shifts using species' ecological and life-history traits, with expectations that shifts should be greater in species with greater dispersal ability, reproductive potential, and ecological generalization. Despite strong theoretical support for species' traits as predictors of range shifts, empirical evidence from contemporary range shift studies remains limited in extent and consensus. We conducted the first comprehensive review of species' traits as predictors of range shifts, collecting results from 51 studies across multiple taxa encompassing over 11,000 species' responses for 54 assemblages of taxonomically related species occurring together in space. We used studies of assemblages that directly compared geographic distributions sampled in the 20th century prior to climate change with resurveys of distributions after contemporary climate change and then tested whether species traits accounted for heterogeneity in range shifts. We performed a formal meta-analysis on study-level effects of body size, fecundity, diet breadth, habitat breadth, and historic range limit as predictors of range shifts for a subset of 21 studies of 26 assemblages with sufficient data. Range shifts were consistent with predictions based on habitat breadth and historic range limit. However, body size, fecundity, and diet breadth showed no significant effect on range shifts across studies, and multiple studies reported significant relationships that contradicted predictions. Current understanding of species' traits as predictors of range shifts is limited, and standardized study is needed for traits to be valid indicators of vulnerability in assessments of climate change impacts.

INTRODUCTION Anthropogenic climate change is reshaping where plants can live. As temperature and precipitation patterns shift, many species are moving to stay within suitable environmental conditions. Predicting how these range shifts will affect future biodiversity requires knowing both where suitable habitats will occur and whether species can reach them. The latter is challenging because dispersal abilities differ widely among species and depend on landscape structure, anthropogenic barriers, and climatic conditions. Large-scale biodiversity forecasts therefore often rely on overly simple assumptions-such as no dispersal, unlimited dispersal, or identical movement rates for all species-thus adding major uncertainty to projections and conservation planning. RATIONALE We used the largest global database of observed plant range shifts (BioShifts; 14,488 records across 6579 plant species) to build models that predict species-specific range shift velocities. Combining 6.8 million plant occurrence records, an ensemble of two top-performing habitat models, and climate projections from 10 global circulation models, we mapped current and future suitable habitats-areas with favorable climate, soil, and land use-at 8 × 8 km resolution for each species. Our analysis covers 18% of known vascular plant species under four greenhouse-gas emissions scenarios for 2081 to 2100. We then overlaid the projected future suitable habitats with species-specific range shift velocities to determine where each species is likely to persist or expand by the end of this century. From these results, we estimated global extinction risks, changes in local species richness, and temporal species turnover in community composition. RESULTS Overall, 7 to 16% of modeled plant species are projected to lose >90% of their range across emissions scenarios, placing them at high risk of extinction. Most of these losses (70 to 80%) stem from suitable habitats disappearing as a result of climate change, rather than from dispersal limitations, indicating that climate-induced habitat loss, rather than an inability to keep pace with changing climate, is the primary threat. Although range shifts are unlikely to prevent many global extinctions, they will strongly reshape local species composition. Plant movements into newly suitable habitats are expected to increase local species richness across 28% of Earth's land surface, maintain latitudinally averaged species richness in the tropics and subtropics (35°S to 35°N), and generate substantial species turnover in mid-latitudes (30° to 50° in both hemispheres). By contrast, in regions north of 50°N, warming is so rapid that most plants cannot keep pace, leading to widespread local extirpations and sharp declines in species richness. CONCLUSION Range shifts can help sustain local species richness but are unlikely to provide much relief from global extinctions. To reduce extinction risks, identifying and protecting climate change refugia to safeguard biodiversity, and expanding ex situ conservation efforts, such as global seed bank and botanic garden networks, may be more effective than facilitating migrations. At the same time, conservation strategies should anticipate changing community compositions and ecosystem functioning as new species arrive and ecosystems reorganize. In high-latitude regions where dispersal lags considerably behind the rapid warming, improving habitat connectivity, reducing human-made barriers, and where appropriate, assisting species movement could help maintain local species richness, ecosystem productivity, carbon sequestration, and ecosystem stability. [Figure: see text].

membership corner ISSN 1948‐6596 from the members On the biogeography of biogeographers Biogeography is concerned with “the study at all possible scales of analysis of the distribution of life across space, and how, through time, it has changed” (Whittaker et al. 2005). It is a long es‐ tablished field of research, with its roots in the early nineteenth century. Recently, the fifth IBS International Meeting was held in Irakleion, Crete, where the latest scientific research in relation to biogeography was presented by biogeographers from around the world. The list of topics covered in this conference was comprehensive: there were four symposia covering Mediterranean biogeogra‐ phy, comparative phylogeography, biogeography and ecology, and analytical advancements in mac‐ roecology and biogeography; and six sessions with contributed papers on island biogeography, cli‐ mate change biogeography, conservation biogeog‐ raphy, palaeoecology, marine biogeography and hot topics in biogeography. Overall, there were 63 talks and 271 poster presentations covering a wide range of biogeographical topics. However I noticed that the geographical origin of the attendees of the conference was less diverse: the majority were from the US and Europe and I was surprised to see only a few re‐ searchers from South America and Asia and practi‐ cally none from Africa. In a relatively advanced field such as biogeography, concerned with distri‐ bution patterns, I found it slightly ironic that the diversity of the biogeographers at this meeting was relatively low. Out of the total of 334 contri‐ butions at the meeting, nearly 60 percent of the authors came from a European institution and 26 percent from North American ones, whereas 7 percent of the first authors came from Central and South America, just about 5 percent from Asia, 2 percent from Oceania, and only 0.3 percent from Africa. So I wondered: where were our colleagues from these regions? I wanted to know whether the low propor‐ tion of researchers from outside of Europe and North America at the IBS meeting is representa‐ tive for the wider academic biogeography commu‐ nity, so I investigated recent contributions pub‐ lished in the four main biogeography journals. I looked up all articles published during 2010 in Journal of Biogeography, Global Ecology and Bio‐ geography, Diversity and Distributions and Ecogra‐ phy, and counted and classified them into six geo‐ graphical regions according to the United Nations Statistics Division (2010) composition of macro‐ geographical regions based on the first mentioned affiliation of the first author of the paper. I consid‐ ered a total of 490 papers in these four journals and found that 45 percent had a first author affili‐ ated with an institution in Europe, 29 percent had a first author from North America, nearly 13 per‐ cent from Oceania, just about 5 percent from Asia, 4 percent from Central and South America, and only 4 percent from Africa. The fact that the proportion of Europeans was relatively high at the conference is logical since the conference was being held in Europe and thus easier to attend for researchers based in this part of the world. The opposite is true for bio‐ geographers from Oceania, who were underrepre‐ sented, probably because of the large distance they had to travel to attend the conference. How‐ ever, considering these minor differences, the geographical distribution of the biogeographers attending the conference seems to correspond with the distribution of those publishing in the four journals. Thus, it would be fair to say that the biogeographers at the IBS meeting were fairly rep‐ resentative of the wider publishing biogeography community in terms of their geographical origin. There are of course various factors contrib‐ uting to the observed patterns, and I will refrain from attempting to explain them. Moreover, the manner in which I classified the publications does not acknowledge the contribution from co‐ authors affiliated with institutions outside of Europe and North America, which is likely to hide a wider international participation. Nevertheless, it is interesting to be aware of the geographical distribution of biogeography researchers and en‐ courage further participation and contributions from underrepresented regions. For example, it frontiers of biogeography 3.1, 2011 — © 2011 the authors; journal compilation © 2011 The International Biogeography Society

Anticipating how species distributions will shift with climate change is key for biodiversity conservation and management. Commonly, species' range shifts are observed by analyzing changes in occurrence or abundance data through time, or predicted across different climate change scenarios by modeling species' climatic niches. However, it remains unclear how well these climate-based forecasts align with empirically documented range shifts from monitoring efforts. Here, we tested the congruence between modeled range shifts, predicted using climatic niche models, and documented range shifts, derived from empirical observations collected over recent decades, for more than 9,500 range shifts across over 3,500 marine and terrestrial species. We found that documented and modeled range shifts tend to align in latitudinal direction, with greater alignment for marine (76%) than terrestrial (56%) cases. However, even when the directions aligned, documented shifts exceeded modeled shifts in 62% of cases, nearly twice as often as they lagged behind (38%), and their median rates were four times faster than those of the modeled shifts. Our findings suggest that climate-based models can approximate observed range dynamics under specific conditions, particularly over long time periods and restricted spatial areas, when habitats remain well connected and under low climate fluctuations over time. These insights provide valuable guidance for both improving predictions and informing responses to climate-driven biodiversity redistribution.

Species are shifting their distribution ranges in response to climate and land-use change. However, the observed range shift patterns are idiosyncratic in rate and direction. Species traits, such as ecological, life-history and movement traits, may play an important role in determining range shifts by influencing a species' capacity to shift successfully. Whilst several studies investigate the role of different species traits in driving range shifts, they generally consider few traits and range shift types. Range shift types such as abundance shift and centroid shift are generally not taken into account. Drivers of range shifts may, however, differ per range shift type. We conducted a meta-analysis to uncover the role of intrinsic factors (nine species functional traits and five spatial abundance characteristics) in explaining six contemporary range shift types (range size changes: expansion/contraction, relative change and rate of change; latitudinal shifts: abundance shift, centroid shift and range margin shift) in European breeding birds (n = 270). We found that the role of intrinsic factors in explaining contemporary range shifts in European breeding birds is indeed range shift type dependent. Natal dispersal distance and clutch size were, for instance, positively related to range size changes, while diet breadth and conservation status showed both negative and positive relationships depending on the range shift type. Acknowledging limitations regarding unevenness of data availability across the study region, the region of study was an important predictor for range size changes, suggesting a relative importance of local context and extrinsic drivers. Future trait-based analyses of range shifts would benefit from accounting for intraspecific variation in functional traits across time and space, the inclusion of additional traits like phenological traits, exposure to environmental pressures, and competitive ability, and should be investigated across multiple scales and for multiple types of range shifts.

Nysius simulans (Stål) is a suctorial, fluid feeding herbivore that can transmit toxins and spread pathogens via saliva and is an economically important pest for soybean in South America. Currently, N. simulans in soybean is predominantly found in Argentina, but future changes in the distribution from both dispersal and range shifts due to climate change may affect soybean cultivation in southern South America. We developed a species distribution model to examine the distribution range of N. simulans. We compared the potential distribution of N. simulans under current and future projected climatic conditions in order to identify future areas of natural occurrence with ecological niche models using Maxent. Current records of N. simulans show that while the species is present in Argentina, and some areas of Brazil, Paraguay, Peru, and Uruguay, our models suggest that many new suitable areas will be available for N. simulans under climate change including other regions of Argentina, and southern Chile. Our results also predict potential future range shifts and distributions into Bolivia, but not Peru nor Brazil. In our model, seasonal trends in temperature were shown to have the greatest contribution to the potential distribution, whereas isothermality (i.e., temperature variability) was correlated to potential future distribution ranges. We conclude that current populations of N. simulans may be expanding its distribution range by diffusion (i.e., range expansion over generations at the margins of populations), and regions with potential future N. simulans distribution should be closely monitored.

news and update ISSN 1948-6596 thesis abstract Potential impacts of climate change on the distribution of fresh- water fishes in French streams and uncertainty of projections Laetitia Buisson PhD, Laboratoire Evolution et Diversite Biologique, Universite Paul Sabatier, Toulouse, and La- boratoire d’Ecologie Fonctionnelle, ENSAT, Castanet-Tolosan, France Current address: Laboratoire Evolution et Diversite Biologique, Universite Paul Sabatier, Tou- louse, France; E-mail: buisson@cict.fr; http://www.edb.ups-tlse.fr/ Climate change and its impact on biodiversity are receiving increasing attention from scientists and people managing natural ecosystems. Recent modifications of climate have induced diverse functional (e.g. phenology, physiology) and struc- tural (e.g. species distribution shifts, range con- traction, local extinctions) responses among or- ganisms (Walther et al. 2002). Given the projec- tions of future climate change, these responses are expected to continue throughout the 21st century and climate change could thus have major consequences on species and assemblages. A common approach to project the potential im- pacts of environmental changes on the distribu- tion of biodiversity is the use of species distribu- tion models (SDM) (e.g. Thuiller 2003). These cor- relative models first relate the present-day spe- cies distribution to a set of climate and other envi- ronmental descriptors. Then, the application of scenarios of future climate changes provides pre- dictions of the habitats potentially suitable in the future for the species. In spite of their widespread use, a growing concern has emerged for the vari- ability in the predicted impacts by such models due to the methodological decisions taken during the modeling process (Thuiller 2004). Improve- ments in the accuracy of predictions combined with an estimation of the uncertainty inherent to those predictions are thus urgently needed. Among freshwater ecosystems, stream fish have no physiological ability to regulate their body temperature and could therefore be very sensitive to climate warming, especially cold-stenotherm fish such as salmonid species. Stream fish also have to cope with hydrological variability of streams and strong anthropogenic pressures (e.g. habitat loss, stream fragmentation). In addition, they have limited dispersal ability within hydro- graphic networks in which they currently live. Yet their response to current and future climate change has been poorly documented and few studies have used SDM to assess the potential consequences of the on-going climate change on freshwater fish species distribution, especially in European streams. In that context, the aim of my PhD thesis was to assess the potential impacts of climate change on fish in French streams, mainly on spe- cies distribution and assemblages’ structure. I used fish data provided by the Office National de l’Eau et des Milieux Aquatiques (ONEMA), the in- stitution in charge of the protection and conserva- tion of freshwater ecosystems in France. These data were combined with climate and environ- mental descriptors through the use of correlative statistical modeling. As my goal was to provide reliable estimates of the future impacts of climate change on stream fish, I have considered recent criticisms (e.g. choice of statistical method, pure bioclimatic models) of species distribution models by justifying each step and optimizing the use of such models. In all, five papers are derived from my PhD work. The first three papers set the bases for the building of the models by considering the uncertainty in predictions, while the latest two assess the impacts of climate change on stream fish species and assemblages. In stream fish ecology, many studies have been conducted to identify the environmental drivers structuring fish assemblages (reviewed in Matthews 1998). It appears that fish species distri- bution and structure of fish assemblages are de- termined by a complex interplay of biotic, abiotic and spatial factors (Jackson et al. 2001). Disentan- © 2009 the authors; journal compilation © 2009 The International Biogeography Society — frontiers of biogeography 1.2, 2009

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