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Aim: Species distribution models (SDMs) have emerged as essential tools in the equipment of many ecologists, useful to explore species distributions in space and time and answering an assortment of questions related to biogeography, climate change biology and conservation biology. Historically, most SDM research concentrated on well‐known organisms, especially vertebrates. In recent years, these tools are becoming increasingly important for predicting the distribution of understudied invertebrate taxa. Here, we reviewed the literature published on main terrestrial arthropod predators (ants, ground beetles and spiders) to explore some of the challenges and opportunities of species distribution modelling in mega‐diverse arthropod groups. Location: Global. Methods: Systematic mapping of the literature and bibliometric analysis. Results: Most SDM studies of animals to date have focused either on broad samples of vertebrates or on arthropod species that are charismatic (e.g. butterflies) or economically important (e.g. vectors of disease, crop pests and pollinators). We show that the use of SDMs to map the geography of terrestrial arthropod predators is a nascent phenomenon, with a near‐exponential growth in the number of studies over the past ten years and still limited collaborative networks among researchers. There is a bias in studies towards charismatic species and geographical areas that hold lower levels of diversity but greater availability of data, such as Europe and North America. Conclusions: Arthropods pose particular modelling challenges that add to the ones already present for vertebrates, but they should also offer opportunities for future SDM research as data and new methods are made available. To overcome data limitations, we illustrate the potential of modern data sources and new modelling approaches. We discuss areas of research where SDMs may be combined with dispersal models and increasingly available phylogenetic and functional data to understand evolutionary changes in ranges and range‐limiting traits over past and contemporary time‐scales. [ABSTRACT FROM AUTHOR]

Aim: Description of the driving forces for genetic divergence is important for understanding spatial pattern of biodiversity and development of conservation plans. Paleo‐climate, geographical barriers and habitat heterogeneity are considered to be the main influential factors; however, an integrative study is still lacking to reveal their interactions. Location: Eastern North America. Methods: Here, we generated MIG‐seq SNPs of 403 Sanguinaria canadensis samples and seven plastome data. The methods of phylogeography and landscape genomics were applied to infer their genetic divergence, demography, species distribution modelling, ecological differentiation and local adaptation. Results: We identified three distinct genetic lineages corresponding to geographical distributions isolated by the Appalachian Mountains and the Mississippi River. Ecological niche modelling and population demographic inference demonstrated that the response of S. canadensis to Pleistocene climate changes was consistent with the pattern of southward contraction during the ice age and northward recolonization during the inter−/postglacial period. Isolation in multiple southern refugia was a key factor resulting in the genetic divergence, whereas secondary contact triggered by repeated range shifts allowed gene flow among different lineages. A greater effect of isolation‐by‐environment than isolation‐by‐distance was founded, which suggested heterogeneous environment was also a promotor of genetic differentiation. Candidate adaptive loci related to transposable elements were identified under the influence of divergent environmental selection. Ecological niche divergence also reflected adaptation to different environments. Main Conclusions: This study revealed that genetic divergence has occurred within S. canadensis populations under the combined effect of paleo‐climate, geographical barriers and habitat heterogeneity, and emphasized the necessity of establishing different conservation units in future biological conservation and management work. [ABSTRACT FROM AUTHOR]

Aim: Decades of research on species distributions has revealed geographic variation in species‐environment relationships for a given species. That is, the way a species uses the local environment varies across geographic space. However, the drivers underlying this variation are contested and still largely unexplored. Niche traits that are conserved should reflect the evolutionary history of a species whereas more flexible ecological traits could vary at finer scales, reflecting local adaptation. Location: North America. Methods: We used mammal observations during a 5‐year period from the iNaturalist biodiversity database and a local ensemble modelling approach to explore spatial variation in American black bear (Ursus americanus) relationships with eight ecological correlates. We tested four biologically driven hypotheses to explain the patterns of local adaptation. We evaluated non‐stationarity in ecological relationships using a Stationarity Index and tested predictive performance using an independent, national‐level animal occurrence data set. Results: We documented considerable spatial non‐stationarity in all eight environmental relationships, with the greatest spatial variation occurring in bear's relationship to climatic factors. Notably, the greatest variation in environmental relationships tended to occur along the current boundaries of the species' range, potentially representing the ecological limits to the species geographic range. We additionally documented that spatial variation in relationships with land cover and anthropogenic factors were best explained by niche conservatism at the subspecies level, whereas climatic relationships were better explained by local adaptation. Main Conclusions: Based on these results, we propose that the current distribution of American black bear is determined by an evolutionary legacy of habitat relationships unique to each subspecies combined with more fine‐scale local adaptation to climatic conditions. This result suggests that black bears should be adaptable to climatic changes over the 21st century and that management of habitat and human‐bear relationships could be considered at the subspecies level. [ABSTRACT FROM AUTHOR]

Aim: Based upon species distribution models (SDMs), many studies have predicted that climate change will cause regional extinctions of tree species within the next 50–100 years. SDM‐based predictions have been challenged on procedural and theoretical grounds, but for tree species they are largely beyond the practical reach of direct experimental validation. Here we report the experimental consequences of moving seedlings from ~50 natural populations of each of two ash (Fraxinus) species to experimental sites spanning a range of 10°C colder to 10°C warmer (mean annual temperature) than home environments. Location: Eastern North America. Methods: We measured population‐by‐test‐site survival percentages and mean trunk diameters at an average age of 35 years. We then used linear, mixed‐effect models to develop transfer functions for each species and predict survival and mean annual growth as functions of fixed and random effects including, especially, the climatic distance (CD) between test site and home environment. Results: Survival and growth were highest at CD ≈ 0 and declined as populations were moved to warmer or colder environments, indicating that survival and growth were optimal when populations were in home‐like climates. However, variance around the model fit was substantial, and we could not statistically detect, even at α =.50, elevated mortality following displacements into environments 3.5°C (white ash) and 4.1°C (green ash) warmer in mean annual temperature. Survival rates of 80%–100% were common even within populations subjected to warming conditions greater than those predicted to cause meso‐scale extinctions in this century. We show that within‐population genetic variance, phenotypic plasticity and idiosyncratic aspects of the non‐climatic environment and its interaction with genotype each likely contributed to these unexpected responses to climatic displacement. Main conclusions: Results emphasize the uncertainty that underlies predictions of climate‐induced extinctions of long‐lived woody plants over time frames of 50 to perhaps 100 years into the future. [ABSTRACT FROM AUTHOR]

Aim We explore the impact of calibrating ecological niche models (ENMs) using (1) native range (NR) data versus (2) entire range (ER) data (native and invasive) on projections of current and future distributions of three Hieracium species. Location H. aurantiacum, H. murorum and H. pilosella are native to Europe and invasive in Australia, New Zealand and North America. Methods Differences among the native and invasive realized climatic niches of each species were quantified. Eight ENMs in BIOMOD were calibrated with (1) NR and (2) ER data. Current European, North American and Australian distributions were projected. Future Australian distributions were modelled using four climate change scenarios for 2030. Results The invasive climatic niche of H. murorum is primarily a subset of that expressed in its native range. Invasive populations of H. aurantiacum and H. pilosella occupy different climatic niches to those realized in their native ranges. Furthermore, geographically separate invasive populations of these two species have distinct climatic niches. ENMs calibrated on the realized niche of native regions projected smaller distributions than models incorporating data from species’ entire ranges, and failed to correctly predict many known invasive populations. Under future climate scenarios, projected distributions decreased by similar percentages, regardless of the data used to calibrate ENMs; however, the overall sizes of projected distributions varied substantially. Main conclusions This study provides quantitative evidence that invasive populations of Hieracium species can occur in areas with different climatic conditions than experienced in their native ranges. For these, and similar species, calibration of ENMs based on NR data only will misrepresent their potential invasive distribution. These errors will propagate when estimating climate change impacts. Thus, incorporating data from species’ entire distributions may result in a more thorough assessment of current and future ranges, and provides a closer approximation of the elusive fundamental niche. [ABSTRACT FROM AUTHOR]

Species occurrence databases and climate databases were used to examine differences in patterns of species experienced climate across latitude for wide-ranging rodents in the central-eastern and western North America. The accumulated data were used to address three questions: (1) Do rodent species in the central and eastern region of North America select habitat at range edges to remain closer to climate conditions at the range core? (2) Is there a trend toward species having greater experienced climate variation consistent with smaller effects of orbitally controlled climate oscillations in the south vs. north? (3) How do species experienced temperature, precipitation, and elevation means and variation in this region compare to rodent species in the adjacent but more heterogeneous western North America? Results showed that central-eastern North American species occur in as wide a range of environmental conditions as available throughout their ranges. These patterns are different from previous findings for rodents in the adjacent western USA and highlight major differences in current structure of species experienced environmental means and variation over latitude for species in spatially heterogeneous, mountainous areas vs. those that occupy flatter lands. The differences are likely important for determining differential response to climate changes. [ABSTRACT FROM AUTHOR]