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Copyright of Journal of Animal Ecology is the property of Wiley-Blackwell and its content may not be copied or emailed to multiple sites or posted to a listserv without the copyright holder's express written permission. However, users may print, download, or email articles for individual use. This abstract may be abridged. No warranty is given about the accuracy of the copy. Users should refer to the original published version of the material for the full abstract. (Copyright applies to all Abstracts.)

Copyright of Ecoscience (Ecoscience) is the property of Taylor & Francis Ltd and its content may not be copied or emailed to multiple sites or posted to a listserv without the copyright holder's express written permission. However, users may print, download, or email articles for individual use. This abstract may be abridged. No warranty is given about the accuracy of the copy. Users should refer to the original published version of the material for the full abstract. (Copyright applies to all Abstracts.)

Trophic specialisation is known to vary across space, but the environmental factors explaining such variation remain elusive. Here we used a global dataset of flower‐visitor networks to evaluate how trophic specialisation varies between latitudinal zones (tropical and temperate) and across elevation gradients, while considering the environmental variation inherent in these spatial gradients. Specifically, we assessed the role of current (i.e., net primary productivity, temperature, and precipitation) and historical (i.e., temperature and precipitation stability) environmental factors in structuring the trophic specialisation of floral visitors. Spatial variations in trophic specialisation were not explained by latitudinal zones or elevation. Moreover, regardless of network location on the spatial gradient, there was a tendency for higher trophic specialisation in sites with high productivity and precipitation, whereas historical temperature stability was related to lower trophic specialisation. We highlight that both energetic constraints in animal foraging imposed by climate and resource availability may drive the global variation in trophic specialisation. [ABSTRACT FROM AUTHOR]

Body size is one of the most influential traits affecting many ecological and physiological processes across animal and plant taxa. Studies of the environmental factors shaping body size patterns may evaluate either temporal or spatial dimensions. Here, we analyzed body size evolution in the radiation of Anolis lizards across both geographical and temporal dimensions. We used a set of macroecological and macroevolutionary methods to test current and past environmental effects on geographical gradients of body size and its evolutionary rates. First, we test whether a set of current ecological/physiological hypotheses (heat balance, productivity and seasonality) explains spatial body size gradients. Second, we evaluate how tempo (i.e. evolutionary rates) and mode (i.e. evolutionary process) of body size evolution changed through time and the role of paleo‐temperatures on rates of body size evolution during the Cenozoic. We did not find a signature of current environmental variables driving spatial body size gradients. By contrast, we found strong support for a correlation between temperature changes (i.e. climate cooling) during the Cenozoic and rates of body size evolution (i.e. body size diversification). We suggest that patterns of body size evolution in Anolis lizards might be influenced by thermoregulatory behavior across clades and regions. [ABSTRACT FROM AUTHOR]

Aim: The tropical niche conservatism (TNC) hypothesis is one of the most prominent evolutionary hypotheses that has been supported as an explanation for the diversity gradients of several animal taxa, mainly vertebrates. However, the validity of TNC for less‐known taxa such as disease vectors is not clear. Here, we test predictions of TNC in driving the geographical co‐occurrence among triatomine species, vector insects of Chagas disease. We aim to infer the relative effects of ecological and evolutionary processes in determining triatomine species richness at broad spatial scales. Location: America. Taxon: Triatominae (Hemiptera: Reduviidae). Methods: We gathered distributional, phylogenetic and climatic information for 63 triatomine species. We apply the phylogenetic field (PF) framework based on the phylogenetic structure of species co‐occurrences, considering their climatic preferences. We defined PFs of species by estimating the phylogenetic structure of species co‐occurrence within a focal species' range. Likewise, climatic conditions within focal species' ranges were defined as their preferred climates. We applied a spatial‐phylogenetic statistical framework to evaluate geographical variation of species' co‐occurrence and tested the significance of PFs based on biogeographically informed null models. Results: Phylogenetic fields of 17 out of 59 triatomine species showed a trend from overdispersed to clustered, coincident with tropical to subtropical–temperate climate. Triatomines co‐occur with more closely related species in temperate areas and more distantly related species in tropical areas. Temperature seasonality was inversely related to the phylogenetic structure of co‐occurrence within species ranges. Main conclusions: Geographical co‐occurrence among triatomine species revealed a tropical to subtropical–temperate gradient from overdispersed to clustered PFs and a correspondence between the type of climate in which these species are found and their PFs. Phylogenetic structure within triatomine ranges is explained by their evolutionary history. Our study provides a methodological framework to evaluate the New World triatomine geographical co‐occurrence patterns under a phylogenetic perspective and our results make an important contribution to the understanding of the broad‐scale biodiversity patterns in Triatominae. [ABSTRACT FROM AUTHOR]

Understanding local coexistence and broad‐scale species co‐occurrence patterns are central questions in ecology and macroecology. Niche theory relates both spatial scales by considering the resources (Eltonian niche) and conditions (Grinnellian niche) used by species and allow us to assess the contribution of these factors for species co‐occurrence. Indeed, combining local field data on diet preferences and climatic variables across species distributions can help us to evaluate their co‐occurrence while jointly considering resources and conditions on niche partitioning. Here, using information drawn from literature, we evaluated the relationship between geographic, climatic (Grinnellian) and trophic (Eltonian) niche dimensions among five highly sympatric felid species in favoring species co‐occurrence at broad spatial scales across the Neotropical region. We obtain potential geographic distributions of species through ecological niche models. Then, we calculated the pairwise species overlaps for each niche dimension and tested for a relationship between each pair of dimensions using Mantel and partial Mantel tests. We found a positive and significant relationship between geographic co‐occurrence and climatic overlap. This relationship remained after controlling for trophic overlap. Geographic and trophic overlap, as well as climatic and trophic overlap, did not show significant relationships. We conclude that the high degree of geographic co‐occurrence among our studied felid species is favored by climate and that their high degree of trophic overlap is not limiting their co‐occurrence pattern. [ABSTRACT FROM AUTHOR]

Aim: Many hypotheses exist to explain the astonishing variation in geographical range size across species, but these have rarely been tested under a unifying framework that simultaneously considers direct and indirect effects of ecological niche processes and evolutionary dynamics. Here, we jointly evaluate ecological and evolutionary hypotheses that might account for global interspecific patterns of range size in the most species‐rich avian order: Passeriformes (perching birds). Location: Global. Time period: Current. Major taxa studied: Order Passeriformes. Methods: We used phylogenetic path analysis to test for the relationship between eight variables and range size. Our list of predictors included a set of niche‐related variables (both Grinellian and Eltonian), species‐specific morphological and life‐history traits (body size, dispersal ability and fertility), extrinsic (human footprint) and evolutionary factors (time since divergence from the closest extant relative). Results: We found that Grinellian (climatic) and Eltonian (trophic) niche breadth are crucial to account for the observed patterns, followed by reproductive effort (as measured by clutch size). We also found a negative relationship between native range size and human footprint. The significant and positive relationship between niche breadth, either Grinnellian or Eltonian, and range size was consistent across all species, irrespective of their migratory/resident status or taxonomic grouping (Passeri versus Tyranni). Main conclusions: Globally, the range sizes of passerine species are associated with the Grinellian niche, meaning that species with broader environmental tolerances exhibit larger geographical ranges. These findings give further empirical support to the positive niche breadth–range size relationship as a general pattern in ecology. [ABSTRACT FROM AUTHOR]

Despite the widespread use of ecological niche models (ENMs) for predicting the responses of species to climate change, these models do not explicitly incorporate any population‐level mechanism. On the other hand, mechanistic models adding population processes (e.g. biotic interactions, dispersal and adaptive potential to abiotic conditions) are much more complex and difficult to parameterize, especially if the goal is to predict range shifts for many species simultaneously. In particular, the adaptive potential (based on genetic adaptations, phenotypic plasticity and behavioral adjustments for physiological responses) of local populations has been a less studied mechanism affecting species' responses to climatic change so far. Here, we discuss and apply an alternative macroecological framework to evaluate the potential role of evolutionary rescue under climate change based on ENMs. We begin by reviewing eco‐evolutionary models that evaluate the maximum sustainable evolutionary rate under a scenario of environmental change, showing how they can be used to understand the impact of temperature change on a Neotropical anuran species, the Schneider's toad Rhinella diptycha. Then we show how to evaluate spatial patterns of species' geographic range shift using such models, by estimating evolutionary rates at the trailing edge of species distribution estimated by ENMs and by recalculating the relative amount of total range loss under climate change. We show how different models can reduce the expected range loss predicted for the studied species by potential ecophysiological adaptations in some regions of the trailing edge predicted by ENMs. For general applications, we believe that parameters for large numbers of species and populations can be obtained from macroecological generalizations (e.g. allometric equations and ecogeographical rules), so our framework coupling ENMs with eco‐evolutionary models can be applied to achieve a more accurate picture of potential impacts from climate change and other threats to biodiversity. [ABSTRACT FROM AUTHOR]

Understanding how the climatic niche of species evolved has been a topic of high interest in current theoretical and applied macroecological studies. However, little is known regarding how species traits might influence climatic niche evolution. Here, we evaluated patterns of climatic niche evolution in turtles (tortoises and freshwater turtles) and whether species habitat (terrestrial or aquatic) influences these patterns. We used phylogenetic, climatic and distribution data for 261 species to estimate their climatic niches. Then, we compared whether niche overlap between sister species was higher than between random species pairs and evaluated whether niche optima and rates varied between aquatic and terrestrial species. Sister species had higher values of niche overlap than random species pairs, suggesting phylogenetic climatic niche conservatism in turtles. The climatic niche evolution of the group followed an Ornstein–Uhlenbeck model with different optimum values for aquatic and terrestrial species, but we did not find consistent evidence of differences in their rates of climatic niche evolution. We conclude that phylogenetic climatic niche conservatism occurs among turtle species. Furthermore, terrestrial and aquatic species occupy different climatic niches but these seem to have evolved at similar evolutionary rates, reinforcing the importance of habitat in understanding species climatic niches and their evolution. [ABSTRACT FROM AUTHOR]

Understanding the climatic and historical factors shaping species richness is a major goal of ecology and biogeography. Consensus on how climate affects species richness is still lacking, but four potential and non-exclusive explanations have emerged: water–energy, where diversity is determined by precipitation and/or temperature; seasonality, where diversity is determined by seasonal variation in climate; heterogeneity, where diversity is determined by spatial variability in climate; and historical climatic stability, where diversity is determined by changes in climate through evolutionary time. Climate–richness relationships are also mediated by historical processes, such as phylogenetic niche conservatism and lineage diversification across regions. We evaluated the effect of climate on species richness gradients of Anolis lizards and tested the role of phylogenetic niche conservatism and regional diversification in the origin and maintenance of climate–richness relationships. Climate had a strong nonstationary relationship with species richness, with strong shared effects among several climate axes. Regional differences in climate–richness relationships suggest different assembly processes between regions. However, we did not find evidence for a role of evolutionary factors, such as phylogenetic niche conservatism or regional diversification, underlying these relationships. We suggest that evolutionary processes affecting climate–richness relationships in Anolis were probably obscured by high dispersal rates between regions. [ABSTRACT FROM AUTHOR]

Copyright of Revista Mexicana de Biodiversidad is the property of Universidad Nacional Autonoma de Mexico, Instituto de Biologia and its content may not be copied or emailed to multiple sites or posted to a listserv without the copyright holder's express written permission. However, users may print, download, or email articles for individual use. This abstract may be abridged. No warranty is given about the accuracy of the copy. Users should refer to the original published version of the material for the full abstract. (Copyright applies to all Abstracts.)

Aim Phylogenetic niche conservatism ( PNC), a pattern of closely related species retaining ancestral niche-related traits over evolutionary time, is well documented for abiotic (Grinellian) dimensions of the ecological niche. However, it remains unclear whether biotic niche (Eltonian) axes are also phylogenetically conserved, even though knowledge of biotic niches is essential to an understanding of the spatiotemporal dynamics of ecological communities. We conduct the first analysis of biotic PNC by evaluating dietary specialization in a vertebrate class. Location Global. Methods We analysed two global compilations of diets of living mammals and a more detailed database for large carnivores together with a species-level phylogeny to evaluate trophic PNC. We searched for evidence of PNC by estimating the phylogenetic signal in distinct descriptors of dietary niche. Results Trophic niches were generally similar among related species but not strongly conserved under a niche-drift macroevolutionary model (Brownian motion). The degree of similarity in trophic niche varied among different taxonomic groups and was, importantly, even within the same group, contingent on the metric of dietary preferences used and the quality of information on the database. Main conclusions Overall, our results showed limited support for PNC in the trophic niche of mammals. However, different data sources and metrics of dietary preferences sometimes offered different conclusions, highlighting the importance of gathering high-quality quantitative data and considering multiple metrics to describe dietary niche breadth and to assess PNC. The fully quantitative database for large carnivores provided some interesting evidence of PNC that could not be detected with semi-quantitative or presence/absence descriptors. Subsequent assessments of phylogenetic imprints on dietary specialization would benefit from considering different metrics and using well-resolved phylogenies jointly with detailed quantitative diet information. While Eltonian trophic niches did not show the same high levels of evolutionary conservatism often displayed by Grinnellian niches, both niche components should be considered to understand range limits of species and clades at biogeographic scales. [ABSTRACT FROM AUTHOR]

Species co-occur with different sets of other species across their geographical distribution,which can be either closely or distantly related. Such co-occurrence patterns and their phylogenetic structure within individual species ranges represent what we call the species phylogenetic fields (PFs). These PFs allow investigation of the role of historical processes-speciation, extinction and dispersal-in shaping species co-occurrence patterns, in both extinct and extant species. Here, we investigate PFs of large mammalian species during the last 3 Myr, and how these correlate with trends in diversification rates. Using the fossil record, we evaluate species' distributional and co-occurrence patterns along with their phylogenetic structure. We apply a novel Bayesian framework on fossil occurrences to estimate diversification rates through time. Our findings highlight the effect of evolutionary processes and past climatic changes on species' distributions and co-occurrences. From the Late Pliocene to the Recent, mammal species seem to have responded in an individualistic manner to climate changes and diversification dynamics, co-occurring with different sets of species from different lineages across their geographical ranges. These findings stress the difficulty of forecasting potential effects of future climate changes on biodiversity. [ABSTRACT FROM AUTHOR]

The current availability of large ecological data sets and the computational capacity to handle them have fostered the testing and development of theory at broad spatial and temporal scales. Macroecology has particularly benefited from this era of big data, but tools are still required to help transforming this data into information and knowledge., Here, we present ' letsR', a package for the R statistical computing environment, designed to handle and analyse macroecological data such as species' geographic distributions (polygons in shapefile format and point occurrences) and environmental variables (in raster format). The package also includes functions to obtain data on species' habitat use, description year and current as well as temporal trends in conservation status as provided by the IUCN RedList online data base., ' letsR' main functionalities are based on the presence-absence matrices that can be created with the package's functions and from which other functions can be applied to generate, for example species richness rasters, geographic mid-points of species and species- and site-based attributes., We exemplify the package's functionality by describing and evaluating the geographic pattern of species' description year in tailless amphibians. All data preparation and most analyses were made using the ' letsR' functions. Our example illustrates the package's capability for conducting macroecological analyses under a single computer platform, potentially helping researchers to save time and effort in this endeavour. [ABSTRACT FROM AUTHOR]

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. [ABSTRACT FROM AUTHOR]

Differential coexistence among species underlies geographical patterns of biodiversity. Understanding such patterns has relied either on ecological or historical approaches applied separately. Recently, macroecology and community phylogenetics have tried to integrate both ecological and historical approaches. However, macroecology is mostly non-phylogenetic, whereas community phylogenetics is largely focused on local scales. Here, we propose a conceptual framework to link macroecology and community phylogenetics by exploring the evolutionary context of large-scale species coexistence, introducing the phylogenetic field concept. This is defined as the phylogenetic structure of species co-occurrence within a focal species' geographical range. We developed concepts and methods for analysing phylogenetic fields and applied them to study coexistence patterns of the bat family Phyllostomidae. Our analyses showed that phyllostomid bats coexist mostly with closely related species, revealing a north -- south gradient from overdispersed to clustered phylogenetic fields. Patterns at different phylogenetic levels (i.e. all species versus close relatives only) presented the same gradient. Results support the tropical niche conservatism hypothesis, potentially mediated by higher speciation rates in the region of origin coupled with shared environmental preferences among species. The phylogenetic field approach enables species-based community phylogenetics, instead of those that are site-based, allowing the description of historical processes at more appropriate macroecological and biogeographic scales. [ABSTRACT FROM AUTHOR]