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Understanding the factors affecting species distributions is a central topic in ecology and biogeography. However, most research on this topic has focused on species inhabiting terrestrial environments. At broad scales, abiotic variables consistently serve as primary determinants of species' distributions. In this study, we investigated the explanatory power of different abiotic variables in determining the distribution patterns of sea snakes on a global scale. Additionally, as the boundaries of realized thermal niches have significant implications for the ecology of species and their geographic distributions, we evaluated the asymmetry of realized thermal limits (i.e., differences in variances between the upper and lower limits of the realized thermal niche). We obtained 10 marine environmental variables from global databases along with >5000 occurrence records for 51 sea snake species in 4 genera across the group's entire known geographic range. Using these data, we employed correlative ecological niche modeling to analyze the influence of the individual variables in explaining species' distributions. To estimate the realized thermal limits of each species, we extracted the mean, minimum, and maximum temperature values at four depths (superficial, mean benthic, minimum benthic, and maximum benthic) for each occurrence record of the species. We then evaluated the asymmetry of the realized thermal niche by measuring and comparing the variances in the upper and lower limits. Both analyses (the importance of variables and realized thermal limit asymmetry) were performed at three taxonomic levels (sea snakes as a lineage of marine-adapted elapids [true sea snakes + sea kraits], subfamily, and genus) and two spatial resolutions. Overall, we found that temperature, silicate, nitrate, salinity, and phosphate concentrations were the most influential factors in explaining the spatial distribution patterns of sea snakes, regardless of taxonomic level or spatial resolution. Similarly, we observed that the realized thermal limits were asymmetric, with a higher variance in the lower limits, and that asymmetry decreased as the taxonomic level and spatial resolution increased.

Species' range size is a fundamental unit of analysis in biodiversity research, given its association with extinction risk and species richness. One of its most notable patterns is its positive relationship with latitude, which has been considered an ecogeographical rule called Rapoport's rule. Despite this rule being confirmed for various taxonomic groups, its validity has been widely discussed and several taxa still lack a formal assessment. Different hypotheses have been proposed to explain their potential mechanisms, with those related to temperature and elevational being the most supported thus far. In this study, we employed two level of analyses (cross-species and assemblage) to investigate the validity of Rapoport's rule in spiny lizards (genus Sceloporus). Additionally, we evaluated four environmental-related hypotheses (minimum temperature, temperature variability, temperature stability since the last glacial maximum, and elevation) posed to explain such pattern, contrasting our results to those patterns expected under a null model of range position. Our results provided support for Rapoport's rule at both levels of analyses, contrasting with null expectations. Consistently, minimum temperature and elevation were the most relevant variables explaining the spatial variation in range size. At the cross-species level, our null simulations revealed that both variables deviated significantly from random expectations. Conversely, at the assemblage level, none of the variables were statistically different from the expected relationships. We discussed the implication of our findings in relation to the ecology and evolution of spiny lizards.

Habitat loss has major impacts on biodiversity. Yet, such impacts are not always linear, as there can be threshold values of habitat amount below which species become extirpated from human-modified landscapes (extinction thresholds). This may be particularly the case for species with high habitat spatial requirements, especially in regions with a long land-use history, which have a lower extinction debt. To address these issues, we evaluated the linear and non-linear effects of landscape-scale forest (habitat) loss on primate species richness in regions with relatively new (Amazon) and old (Atlantic Forest) histories of land-use change. We also evaluated the role of mean home range size in regulating species responses to forest loss. Extinction thresholds were higher in the Atlantic Forest (78% remaining forest cover) than in the Amazon (45%), but primate-landscape associations were stronger in the Amazon. Thus, despite its recent land-use history, Amazon primates are more sensitive to habitat loss. As predicted, mean home range size decreased with forest loss in both biomes. Our findings highlight the importance of stopping deforestation in both biomes to maintain habitat amount above these thresholds. Yet, as

Area-based strategies for conservation include defining species richness and rarity hotspots. However, excluding vulnerable species (e.g., with restricted distribution and categorized as threatened), in establishing such hotspots may limit their representativeness, so the convenience of asserting them has been widely debated. To inform conservation assessments for the New World leaf-nosed bats (Chiroptera: Phyllostomidae), we identified hotspots based simultaneously on species richness and rarity of 214 species. We projected species range maps on a 0.5° × 0.5° longitude-latitude grid, from which we built a presence-absence matrix with 6951 sites. Using range-diversity plots, we described richness-rarity hotspots (sites with high species richness and presence of rare species) and poorness-rarity hotspots (with low species richness and presence of rare species). We assess the representativeness of the hotspots within established protected areas using the World Database on Protected Areas. The richness-rarity hotspot was located in the Andean zone from Peru to Panama within which 46 species of phyllostomid bats are distributed and 37% of its surface is protected. While the poorness-rarity hotspot was located in the northern region of Mexico and the Caribbean with 50 phyllostomid bats species and 19% of its surface protected. We hope that our analysis represents a relevant tool for the conservation of phyllostomid bats, which provide several ecosystem services and are currently facing different threats derived from anthropogenic activities.

Empirical evidence has shown that introduced honeybees, Apis mellifera L., can change the structural organization of ecological networks involving pollinators and flowering plants. In this case, studies have shown that A. mellifera is highly connected within networks (i.e., high interactive role) mainly due to its high abundances, long colony lifetime, generalist diet, and great capacity of spread and adaptation to new environments. However, there is little knowledge on how the interactive role of A. mellifera in these flower-visitor networks changes spatially and the potential correlates of such variation across ecological and geographical gradients worldwide. In this study, we evaluated how native and exotic distribution ranges, local climate, human influence (i.e., anthropogenic disturbance), and latitude shape the interactive role of the honeybee in plant-floral visitor networks globally. To achieve that, we compiled 95 weighted plant-floral visitor networks encompassing ca. 87 degrees of latitude and 227 degrees of longitude across the globe. We found that the interactive role of A. mellifera is higher in its exotic range than in the native distributional range and positively associated with mean annual temperature and precipitation. Further, the interactive role of A. mellifera was high at intermediate values of global human influence and increased with latitude. Our findings help us to understand how different drivers related to rapid global change could affect the capacity of A. mellifera to colonize and increase its impact on other pollinator species in different environments.

The small size, degree of isolation, and particular evolutionary processes occurring in islands make them highly diverse and an essential target for conservation. For the same characteristics, they are also extremely vulnerable to human-mediated disturbances. During the last centuries, nearly 80% of species extinctions have occurred on islands. While there is information on the human threats, level of protection, and conservation importance of islands, an integrative picture combining these aspects and aimed at determining conservation priorities to inform decision-making is still missing. Here, we jointly analyzed these three aspects producing a worldwide island conservation assessment based on terrestrial vertebrates. Considering the Aichi target of >17% of protection and all protected area categories, we found that 5397 islands, encompassing a quarter of the worldwide island area, face high human modification and have a low level of protection, with 33% of them showing extreme levels of human modification. Also, if we were to consider the new threshold of protected area coverage proposed to accurately protect the world’s biodiversity and ecosystems (Nature Needs Half initiative), 77% of the world’s islands would face this dramatic scenario. Furthermore, most large islands harboring the highest number of threatened vertebrates are found on this critical situation (low protection and high human modification). Based on the analysis of these conservation scenarios, we identified potential priority islands that provide opportunities to improve island conservation worldwide. The mbest opportunities are located in 58 islands with a low level of protection and human modification, which harbor more than 5 threatened vertebrates’ species and are located in different regions of the world.

Abstract Despite the long-standing interest in the organization of ant communities across elevational gradients, few studies have incorporated the evolutionary information to understand the historical processes that underlay such patterns. Through the evaluation of phylogenetic α and β-diversity, we analyzed the structure of leaf-litter ant communities along the Cofre de Perote mountain in Mexico and evaluated whether deterministic- (i.e., habitat filtering, interspecific competition) or stochastic-driven processes (i.e., dispersal limitation) were driving the observed patterns. Lowland and some highland sites showed phylogenetic clustering, whereas intermediate elevations and the highest site presented phylogenetic overdispersion. We infer that strong environmental constraints found at the bottom and the top elevations are favoring closely-related species to prevail at those elevations. Conversely, less stressful climatic conditions at intermediate elevations suggest interspecific interactions are more important in these environments. Total phylogenetic dissimilarity was driven by the turnover component, indicating that the turnover of ant species along the mountain is actually shifts of lineages adapted to particular locations resembling their ancestral niche. The greater phylogenetic dissimilarity between communities was related to greater temperature differences probably due to narrow thermal tolerances inherent to several ant lineages that evolved in more stable conditions. Our results suggest that the interplay between environmental filtering, interspecific competition and habitat specialization plays an important role in the assembly of leaf-litter ant communities along elevational gradients.

By the end of this century, human-induced climate change and habitat loss may drastically reduce biodiversity, with expected effects on many amphibian lineages. One of these effects is the shift in the geographic distributions of species when tracking suitable climates. Here, we employ a macroecological approach to dynamically model geographic range shifts by coupling ecological niche models and eco-evolutionary mechanisms, aiming to assess the probability of evolutionary rescue (i.e., rapid adaptation) and dispersal under climate change. Evolutionary models estimated the probability of population persistence by adapting to changes in the temperature influenced by precipitation in the following decades, while compensating the fitness reduction and maintaining viable populations in the new climates. In addition, we evaluated emerging patterns of species richness and turnover at the assemblage level. Our approach was able to identify which amphibian populations among 7,193 species at the global scale could adapt to temperature changes or disperse into suitable regions in the future. Without evolutionary adaptation and dispersal, 47.7% of the species could go extinct until the year 2,100, whereas adding both processes will slightly decrease this extinction rate to 36.5%. Although adaptation to climate is possible for populations in about 25.7% of species, evolutionary rescue is the only possibility to avoid extinction in 4.2% of them. Dispersal will allow geographic range shifts for 49.7% of species, but only 6.5% may avoid extinction by reaching climatically suitable environments. This reconfiguration of species distributions and their persistence creates new assemblage-level patterns at the local scale. Temporal beta-diversity across the globe showed relatively low levels of species turnover, mainly due to the loss of species. Despite limitations with obtaining data, our approach provides more realistic assessments of species responses to ongoing climate changes. It shows that, although dispersal and evolutionary rescue may attenuate species losses, they are not enough to avoid a significant reduction of species’ geographic ranges in the future. Actions that guarantee a higher potential of adaptation (e.g., genetic diversity through larger population sizes) and increased connectivity for species dispersion to track suitable climates become essential, increasing the resilience of biodiversity to climate change.

Historical climate adaptation can give insight into the potential for adaptation to contemporary changing climates. Here Bennett et al. investigate thermal tolerance evolution across much of the tree of life and find different effects of ancestral climate on the subsequent evolution of ectotherms vs. endotherms.

Biotic interactions are a key component of the proper functioning of ecosystems. However, information on biotic interactions is spatially and taxonomically biased and limited to several groups. The most efficient strategy to fill these gaps is to combine spatial information (species ranges) with different sources of information (functional and field data) to infer potential interactions. This approach is possible due to the fact that there is a correspondence between the traits of two trophic levels (e.g., predator and prey sizes are correlated). Therefore, our objective was to evaluate the performance of the joint use of spatial, functional and field data to infer properties of the predator–prey interaction for five neotropical cats. To do this, we used presence–absence matrices to obtain lists of potential prey species per grid-cell for each predator range. These lists were filtered according to different criteria (models), and for each model, an interaction property was estimated and compared with field observations. Our results show that the use of functional information and co-occurrence allows us to generate values similar to those observed in the field. We also observed that there were differences in model performance related to the intrinsic characteristics of the predator (body size) and the interaction property being evaluated.

Studies at local spatial scales have shown that the generalist honeybee Apis mellifera L. can strongly affect the structural organization and properties of pollination networks. However, there is still little knowledge on how the connectivity of the honeybee within networks (i.e., interactive role) could affect pollination networks at a global scale. To fill this gap, we evaluated how the interactive role of A. mellifera could affect niche overlap, specialization, and robustness of pollination networks. We used 109 weighted pollination networks spread across about 94 degrees of latitude and 227 degrees of longitude. We developed a new standardized framework based on species removal to assess the impact of the honeybee on plant-pollinator networks. We found that when the honeybee was removed from the networks, plant species had less niche overlap (i.e., shared fewer interactions via their pollinators) and the networks became more specialized and more robust to species extinctions. Our findings indicate that A. mellifera’s effects on pollination networks vary geographically and could influence several ecological and evolutionary factors acting at local scales, including pollination services. We hope this contribution will stimulate new macroecological studies involving abundant and generalist species and their functional roles within ecological communities.

Knowledge about the dynamics of regional diversity patterns is a foundation on which measures aimed to protect diversity dimensions in the light of climate change can be constructed. Here, we describe taxonomic, phylogenetic, and functional diversity patterns of amphibians in the Yucatan Peninsula and their representation in the current protected area system. We stacked current and future potential distribution models to estimate taxonomic diversity and, based on the most recent amphibian phylogeny and nine functional traits, we measured phylogenetic and functional diversity. Independent phylogenetic and functional metrics were obtained by applying null models that allowed us to identify the presumably signature mechanisms underlying assemblage formation. We evaluated the effectiveness of the protected areas in protecting diversity dimensions across scenarios. We found phylogenetic and functional clustering as a result of environmental filters that have allowed only recently diverged species with converged functional traits to establish. Nevertheless, random assemblages are more widespread possibly due to the opposite directions in which competition and environmental filtering are acting. Overall, a decrease in all diversity dimensions is projected under future climate change scenarios compared with the current time. None of the protected areas evaluated were effective in protecting diversity dimensions, stressing the need to complete the existing protected areas network.

Las montañas cubren un 12% de la superficie terrestre y un 23% del territorio de México. Tomando como base lo anterior, el objetivo es poner al alcance de los lectores una definición actual y objetiva de lo que es una montaña, así como informarles de manera simple acerca de su importancia biológica como guardianas de la biodiversidad y proveedoras de servicios ecosistémicos. Para esto, realizamos una búsqueda documental sobre el tema ecología de montaña. Nuestro principal interés es que se reconozcan a las montañas como sitios prioritarios para la conservación debido a los múltiples beneficios que suministran a la humanidad. Desafortunadamente, muchas de las montañas en el mundo y en México se encuentran bajo diferentes amenazas.

Eigenfunction analyses have been widely used to model patterns of autocorrelation in time, space and phylogeny. In a phylogenetic context, Diniz-Filho et al. (1998) proposed what they called Phylogenetic Eigenvector Regression (PVR), in which pairwise phylogenetic distances among species are submitted to a Principal Coordinate Analysis, and eigenvectors are then used as explanatory variables in regression, correlation or ANOVAs. More recently, a new approach called Phylogenetic Eigenvector Mapping (PEM) was proposed, with the main advantage of explicitly incorporating a model-based warping in phylogenetic distance in which an Ornstein-Uhlenbeck (O-U) process is fitted to data before eigenvector extraction. Here we compared PVR and PEM in respect to estimated phylogenetic signal, correlated evolution under alternative evolutionary models and phylogenetic imputation, using simulated data. Despite similarity between the two approaches, PEM has a slightly higher prediction ability and is more general than the original PVR. Even so, in a conceptual sense, PEM may provide a technique in the best of both worlds, combining the flexibility of data-driven and empirical eigenfunction analyses and the sounding insights provided by evolutionary models well known in comparative analyses.

Ecological niche modeling (ENM) is a broadly used tool in different fields of plant ecology. Despite the importance of edaphic conditions in determining the niche of terrestrial plant species, edaphic data have rarely been included in ENMs of plant species perhaps because such data are not available for many regions. Recently, edaphic data has been made available at a global scale allowing its potential inclusion and evaluation on ENM performance for plant species. Here, we take advantage of such data and address the following main questions: What is the influence of distinct predictor variables (e.g. climatic vs edaphic) on different ENM algorithms? and what is the relationship between the performance of different predictors and geographic characteristics of species? We used 125 plant species distributed over the Neotropical region to explore the effect on ENMs of using edaphic data available from the SoilGrids database and its combination with climatic data from the CHELSA database. In addition, we related these different predictor variables to geographic characteristics of the target species and different ENM algorithms. The use of different predictors (climatic, edaphic, and both) significantly affected model performance and spatial complexity of the predictions. We showed that the use of global edaphic plus climatic variables generates ENMs with similar or better accuracy compared to those constructed only with climate variables. Moreover, the performance of models considering these different predictors, separately or jointly, was related to geographic properties of species records, such as number and distribution range. The large geographic extent, the variability of environments and the different species' geographical characteristics considered here allowed us to demonstrate that global edaphic data adds useful information for plant ENMs. This is particularly valuable for studies of species that are distributed in regions where more detailed information on soil properties is poor or does not even exist.

Diferentes métodos han sido propuestos para evaluar el grado de señal filogenética (autocorrelación) en los rasgos macroecológicos. Estos métodos son útiles para desarrollar maneras alternativas de evitar el problema de la falta de independencia entre especies y, actualmente, han demostrado ser importantes para inferir la velocidad de evolución de un rasgo al compararlo con modelos evolutivos alternativos, tales como el movimiento Browniano o el proceso Ornstein-Uhlenbeck (OU). Recientemente, desarrollamos un método llamado Curva de Señal-Representación Filogenética (PSR, por sus siglas en inglés), una expansión de la regresión de autovectores filogenéticos (PVR, por sus siglas en inglés) propuesto en 1998, que consiste en estimar diferentes coeficientes de determinación mediante la regresión de un rasgo de interés contra los autovectores extraídos de una matriz de distancias filogenéticas. El primer modelo únicamente utiliza los primeros de estos autovectores como variable explicativa, el segundo modelo utiliza tanto los primeros como los segundos autovectores y así sucesivamente. Posteriormente, los coeficientes de determinación resultantes son graficados contra los autovalores acumulados y la forma de esta curva es relacionada con modelos evolutivos determinando la variación del rasgo (i.e. un patrón lineal es esperado bajo movimiento Browniano). Aquí, aplicamos la curva PSR para estudiar los patrones de variación inter específica en la talla corporal y tamaño de área de distribución de los carnívoros a nivel mundial y comparamos dichas curvas con aquellas simuladas bajo diferentes modelos de evolución. Nuestros resultados apoyan inequívocamente nuestras expectativas basadas en estudios previos acerca de la talla corporal presentando una fuerte señal filogenética, aproximada por un patrón OU con baja restricción, mientras el tamaño de área de distribución es más variable y mejor ajustado por un modelo nulo sugiriendo la ausencia de señal filogenética.

Environmental gradients (EG) related to climate, topography and vegetation are among the most important drivers of broad scale patterns of species richness. However, these different EG do not necessarily drive species richness in similar ways, potentially presenting synergistic associations when driving species richness. Understanding the synergism among EG allows us to address key questions arising from the effects of global climate and land use changes on biodiversity. Herein, we use variation partitioning (also know as commonality analysis) to disentangle unique and shared contributions of different EG in explaining species richness of Neotropical vertebrates. We use three broad sets of predictors to represent the environmental variability in (i) climate (annual mean temperature, temperature annual range, annual precipitation and precipitation range), (ii) topography (mean elevation, range and coefficient of variation of elevation), and (iii) vegetation (land cover diversity, standard deviation and range of forest canopy height). The shared contribution between two types of EG is used to quantify synergistic processes operating among EG, offering new perspectives on the causal relationships driving species richness. To account for spatially structured processes, we use Spatial EigenVector Mapping models. We perform analyses across groups with distinct dispersal abilities (amphibians, non-volant mammals, bats and birds) and discuss the influence of vagility on the partitioning results. Our findings indicate that broad scale patterns of vertebrate richness are mainly affected by the synergism between climate and vegetation, followed by the unique contribution of climate. Climatic factors were relatively more important in explaining species richness of good dispersers. Most of the variation in vegetation that explains vertebrate richness is climatically structured, supporting the productivity hypothesis. Further, the weak synergism between topography and vegetation urges caution when using topographic complexity as a surrogate of habitat (vegetation) heterogeneity.

Understanding the drivers of plant-insect interactions is still a key issue in terrestrial ecology. Here, we used 30 well-defined plant-herbivore assemblages to assess the effects of host plant phylogenetic isolation and origin (native vs. exotic) on the species richness, composition and specialization of the insect herbivore fauna on co-occurring plant species. We also tested for differences in such effects between assemblages composed exclusively of exophagous and endophagous herbivores. We found a consistent negative effect of the phylogenetic isolation of host plants on the richness, similarity and specialization of their insect herbivore faunas. Notably, except for Jaccard dissimilarity, the effect of phylogenetic isolation on the insect herbivore faunas did not vary between native and exotic plants. Our findings show that the phylogenetic isolation of host plants is a key factor that influences the richness, composition and specialization of their local herbivore faunas, regardless of the host plant origin.

Broad-scale patterns of species richness result from differential coexistence among species in distinct regions of the globe, determined by the species’ ranges and their properties such as size, shape and location. Thus, species richness and ranges are inherently linked. These two biodiversity features also yield primary information for conservation assessments. However, species richness and range size have been usually studied separately and no formal analytical link has been established. In my PhD thesis, I applied and extended a recently developed conceptual and methodological framework to study geographical association among species and similarity among sites. This range–diversity framework, along with stochastic simulation modelling, allowed me to jointly evaluate the relationship between diversity and distribution, to infer potential processes underlying composite patterns of phyllostomid bats, and to use this approach to inform conservation assessments for the Mexican avifauna. I highlight the need to explore composite patterns for understanding biodiversity patterns and show how combining diversity and distributional data can help describe complex biogeographical patterns, providing a transparent and explicit application for initial conservation assessments.

Extinction risk and body size have been found to be related in various vertebrate groups, with larger species being more at risk than smaller ones. We checked whether this was also the case for snakes by investigating extinction risk-body size relationships in the New World's Colubroidea species. We used the IUCN Red List risk categories to assign each species to one of two broad levels of threat (Threatened and Non-Threatened) or to identify it as either Data Deficient or Not-Evaluated by the IUCN. We also included the year of description of each species in our analysis as this could affect the level of threat assigned to it (earlier described species had more time to gather information about them, which might have facilitated their evaluation). Also, species detectability could be a function of body size, with larger species tending to be described earlier, which could have an impact in extinction risk-body size relationships. We found a negative relationship between body size and description year, with large-bodied species being described earlier. Description year also varied among risk categories, with Non-Threatened species being described earlier than Threatened species and both species groups earlier than Data Deficient species. On average, Data Deficient species also presented smaller body sizes, while no size differences were detected between Threatened and Non-Threatened species. So it seems that smaller body sizes are related with species detectability, thus potentially affecting both when a species is described (smaller species tend to be described more recently) as well as the amount of information gathered about it (Data Deficient species tend to be smaller). Our data also indicated that if Data Deficient species were to be categorized as Threatened in the future, snake body size and extinction risk would be negatively related, contrasting with the opposite pattern commonly observed in other vertebrate groups.

Species richness and range size are key features of biogeographic and macroecological analyses, which can yield a first assessment tool to define conservation priorities. Here we combined both features in a simultaneous analysis, based on range-diversity plots, to identify sets of rich-rare (high species richness with restricted ranges) and poor-rare cells (low species richness with restricted ranges). We applied this analysis to the anurans of South America and evaluated the representation of those sets of cells within the protected area system. South American anurans showed high species richness in the Brazilian Atlantic Forest and East Tropical Andes, while regions harboring most of the rare species were concentrated in the Andes and Atlantic Coast from North-Eastern Brazil to River Plate. Based on such patterns, we identified as rich-rare cells the Brazilian Atlantic Forest and Tropical Andes and as poor-rare cells the southern part of Andes and Uruguay. A low fraction of both sets of cells was represented within the protected area system. We show that a simultaneous consideration of species richness and rarity provides a rapid assessment of large-scale biodiversity patterns and may contribute to the definition of conservation priorities.