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Menegotto and colleagues' (2019) commentary on our paper (Kinlock et al., 2018) does not negate our findings, but by recategorizing and reanalysing a portion of our data set, advances our knowledge of the latitudinal diversity gradients (LDGs) in marine ecosystems, particularly emphasizing different findings for benthic LDGs as a result of the recategorization of the data. Furthermore, we see the contribution by Menegotto et al. (2019) as highlighting the importance of scientific transparency; we believe that this insight into the nature of LDGs in marine systems would have been delayed, if not unobtainable, had we not provided fully transparent methods and complete data in our paper. [ABSTRACT FROM AUTHOR]

Species distribution models ( SDMs) are used to inform a range of ecological, biogeographical and conservation applications. However, users often underestimate the strong links between data type, model output and suitability for end-use. We synthesize current knowledge and provide a simple framework that summarizes how interactions between data type and the sampling process (i.e. imperfect detection and sampling bias) determine the quantity that is estimated by a SDM. We then draw upon the published literature and simulations to illustrate and evaluate the information needs of the most common ecological, biogeographical and conservation applications of SDM outputs. We find that, while predictions of models fitted to the most commonly available observational data (presence records) suffice for some applications, others require estimates of occurrence probabilities, which are unattainable without reliable absence records. Our literature review and simulations reveal that, while converting continuous SDM outputs into categories of assumed presence or absence is common practice, it is seldom clearly justified by the application's objective and it usually degrades inference. Matching SDMs to the needs of particular applications is critical to avoid poor scientific inference and management outcomes. This paper aims to help modellers and users assess whether their intended SDM outputs are indeed fit for purpose. [ABSTRACT FROM AUTHOR]

The study of biodiversity started as a single unified field that spanned both ecology and evolution and both macro and micro phenomena. But over the 20th century, major trends drove ecology and evolution apart and pushed an emphasis towards the micro perspective in both disciplines. Macroecology and macroevolution re‐emerged as self‐consciously distinct fields in the 1970s and 1980s, but they remain largely separated from each other. Here, we argue that despite the challenges, it is worth working to combine macroecology and macroevolution. We present 25 fundamental questions about biodiversity that are answerable only with a mixture of the views and tools of both macroecology and macroevolution. [ABSTRACT FROM AUTHOR]

Motivation: Amphibians are a diverse vertebrate group with more than 8,000 species, which is an important part of major terrestrial and freshwater ecosystems. Unfortunately, amphibians are experiencing a worldwide population decline. Trait information is important for understanding the causes of endangerment. Additionally, such information is essential for ecological and evolutionary studies using trait‐based approaches. However, such data are scarcer for amphibians than for any other terrestrial vertebrate groups. To fill this gap, we collected morphological traits of global amphibians available from the literature and compiled a database to facilitate future studies. Main types of variables contained: Forty‐two morphological traits of Anura, 27 morphological traits of Caudata and 37 morphological traits of Gymnophiona. Spatial location and grain: Global. Major taxa: Amphibia. Level of measurement: Species. Software format:.csv. [ABSTRACT FROM AUTHOR]

The cover image, by Ana Ceia ‐ Hasse et al., is based on the Research Paper Global exposure of carnivores to roads, DOI: 10.1111/geb.12564. Photo Credit: Joaquim Pedro Ferreira. [ABSTRACT FROM AUTHOR]

The cover image, by Leonardo D. Fernández et al., is based on the Research Paper Water–energy balance, past ecological perturbations and evolutionary constraints shape the latitudinal diversity gradient of soil testate amoebae in south ‐ western South America, DOI: 10.1111/geb.12478. Photo Credit: Leonardo D. Fernández and Fabiola Barrientos ‐ Loebel. [ABSTRACT FROM AUTHOR]

Aim: Across a variety of taxonomic scales, species diversity is unevenly distributed among its constituent units, and clades with few species are more common than expected assuming homogeneous rates of speciation and extinction among lineages. In order to explain the prevalence of species‐poor families among a global and species‐rich radiation of passerine birds, we test whether these groups share common eco‐morphological, geographical and phylogenetic attributes. Location: Global. Time period: Late Oligocene to the present day. Major taxa studied: The Corvides (c. 790 species). Methods: We obtained 10 linear measurements of external morphology for 782 species of corvoid passerines. Using these measurements as a proxy for species ecology, we assessed the positioning of corvoid families in eco‐morphological trait space and how these factors were associated with their species richness and rates of lineage diversification. Subsequently, we compared these same characteristics (species richness, morphological positioning and rates of lineage diversification) between families that are currently endemic to the Australasian ancestral area of the Corvides with those that have dispersed and diversified throughout other continental and insular landmasses. Results: Families with low species richness and rates of diversification tend to occupy the most peripheral positions in eco‐morphological trait space, with almost all of these groups being endemic to Australasia. The peripheral eco‐morphological positioning of the Australasian groupings is generally greater than expected upon accounting for differences in phylogenetic isolation and heterogeneity in rates of trait evolution, implying that species‐poor corvoid families repeatedly evolved towards marginal areas of morphospace. Main conclusions: The over‐representation of species‐poor clades across diverse sets of organismal groups is consistent with their evolution towards, and the maintenance in, marginal areas of ecological niche space. The evolution of peripheral eco‐morphological characters represents a potentially significant limit to rates of range expansion and lineage diversification. [ABSTRACT FROM AUTHOR]

Aim: The aim was to quantify gradients in local richness levels, feeding strategies and body mass distributions in bats and relate them to environmental variation and habitat disturbance. Location: The New World. Time period: Present day. Major taxa studied: Bats. Methods: I assembled 152 local species inventories from the published literature, which include 245 species, along with body mass measurements and dietary categorizations. I quantified species richness using the Chao 1 extrapolator, obtained mean mass values for the inventories and computed proportions of species and of individuals belonging to different feeding guilds. I reduced the dimensonality of environmental variables using factor analysis and regressed richness values upon the factor scores. Results: South of the Tropic of Cancer, bats exhibit sharp increases in local diversity, the abundance of frugivores and nectarivores, and mean body mass. These offsets are driven by increases in the richness and abundance of the leaf‐nosed bats (Phyllostomidae). Richness steeply declines near the Tropic of Capricorn, but the other variables do not trend strongly at this point. Most of the variance is explained by mean annual temperature, temperature seasonality and precipitation. There is no direct evidence that richness is lower in disturbed landscapes. Main conclusions: The great radiation of phyllostomids in the Neotropics has created a uniquely rich biota. The reason that phyllostomids are now absent from the northern temperate zone might be that they are mostly frugivores or nectarivores. Therefore, they have prospered only in regions that provide fruit and nectar year‐round. Thus, biotic interactions might be the immediate cause of the latitudinal diversity gradient in New World bats. If so, then the biogeographical break is driven by environmental factors and is not a historical artefact. These results suggest that a more nuanced consideration of latitudinal gradients will prove to be helpful when it comes to studying many taxonomic groups. [ABSTRACT FROM AUTHOR]

Motivation: over the last 12 years I have been collecting trait and geographic data on lizards. These data could be useful for scientists studying this remarkable reptilian radiation. Furthermore, as published data for some of the less well known species are scarce, I hope this study can initiate a community effort to fill in data gaps. I present geographical, morphological, ecological, physiological and life history data for the 6,657 known species of lizards. I further indicate whether there are phylogenetic data associated with them, and their threat assessment, if they have one. I present descriptive statistics regarding these traits and point to avenues for future research using the dataset. Main types of variable contained: body size, ecological, thermal biology, geographic, phylogenetic and life history data. Spatial location: Global. Time period: data are for species known from living, or recently extinct species. Most underlying data were collected during the 20th and 21st centuries. Major taxa: Reptilia, Sauria (Squamata, including Amphisbaenia but excluding Serpentes). Level of measurement: species. Software format: csv. [ABSTRACT FROM AUTHOR]

Abstract: Aim: Understanding the evolution of the latitudinal diversity gradient (i.e. increase in species diversity towards the tropics) is a prominent issue in ecology and biogeography. Disentangling the relative contributions of environment and evolutionary history in shaping this gradient remains a major challenge because their relative importance has been found to vary across regions and taxa. Here, using the global distributions and a molecular phylogeny of Rhododendron, one of the largest genera of flowering plants, we aim to compare the relative contributions of contemporary environment, evolutionary time and diversification rates in generating extant species diversity patterns. Location: Global. Time period: Undefined. Major taxa studied: Rhododendron. Methods: We compiled the global distributions of all Rhododendron species, and constructed a dated molecular phylogeny using nine chloroplast genes and seven nuclear regions. By integrating these two datasets, we estimated the temporal trends of Rhododendron diversification, and explored the global patterns of its species diversity, net diversification rates, and species ages. Next, we reconstructed the geographical ancestral area of the clade. Finally, we compared the relative contribution of contemporary environment, time‐for‐speciation, and diversification rates on the species diversity pattern of Rhododendron. Results: In contrast to the predictions of the time‐for‐speciation hypothesis, we found that although Rhododendron originated at a temperate latitude, its contemporary species diversity is highest in the tropics/subtropics, suggesting an into‐the‐tropics colonization for this genus. We found that the elevated diversification induced by heterogeneous environmental conditions in the tropics/subtropics shapes the global pattern of Rhododendron diversity. Main conclusions: Our findings support tropical and subtropical mountains as not only biodiversity and endemism hotspots, but also as cradles for the diversification of Rhododendron. Our study emphasizes the need of unifying ecological and evolutionary approaches in order to gain comprehensive understanding of the mechanisms underlying the global patterns of plant diversity. [ABSTRACT FROM AUTHOR]

Aim Global biomes are often classified by mean annual temperature and precipitation, but there is significant overlap between biomes, making it difficult to interpret the role of climate in the distribution of biomes globally. Climate predictability (including long-term reliability of both seasonality and inter-annual variability) varies considerably between biomes and regulates biodiversity distribution, adaptation and evolution, but its global pattern has rarely been investigated. The aim of this study was to characterize climatic space quantitatively for major biomes of the world using temperature and precipitation predictability, and to interpret its biological implications under future climate change. Location Global. Time Period 1901-2012. Methods We calculated global gridded temperature and precipitation predictability based on an information theory approach, and compared climatic spaces defined by these measures within and across biomes. Results We show that temperature predictability has a clear latitudinal gradient, whereas precipitation predictability is geographically variable. We further show that temperature and precipitation predictability form distinct climatic spaces for major biomes across the globe, and importantly, temperature and precipitation predictability can robustly distinguish biomes that are overlapping in mean annual climate statistics. Main conclusions Climatic space created by temperature and precipitation predictability supplements the traditional biome-specific climatic spaces created by annual mean temperature and total precipitation. Quantifying measures of climate predictability helps us to understand adaptation strategies adopted by local organisms within and across biomes. Our results show that quantifying climate predictability is a simple and effective way to delineate more robustly biome climate space and its influences on macroecology and evolutionary biology, which in turn could underpin conservation efforts under future climate change, especially when prevailing climates are comparable in terms of magnitude. [ABSTRACT FROM AUTHOR]

Aim Knowledge of species geographical distributions is critical for many ecological and evolutionary questions and underpins effective conservation decision-making, yet it is usually limited in spatial resolution or reliability. Over large spatial extents, range predictions are typically derived from expert knowledge or, increasingly, species distribution models based on individual occurrence records. Expert maps are useful at coarse resolution, where they are suitable for delineating unoccupied regions. In contrast, point records typically provide finer-scale occurrence information that can be characterized for its environmental association, but usually suffers from observer biases and does not representatively or fully address the geographical or environmental range occupied by a species. Innovation We develop a new modelling methodology to combine the complementary informative attributes of both data types to improve fine-scale, large-extent predictions. We use expert delineations to constrain predictions of a species distribution model parameterized with incidental point occurrence records. We introduce a maximum entropy approach for combining the two data types and generalize it to Poisson point process models. We illustrate critical decision making during model construction using two detailed case studies and illustrate features more generally with applications to species with vastly different range and data attributes. Our methods are illustrated in the Supporting Information and with a new R package, bossMaps, that integrates with existing generalized linear modelling and Maxent software. Main conclusions Our modelling strategy flexibly accommodates expert maps with different levels of bias and precision. The approach can also be useful with other coarse sources of spatially explicit information, including habitat associations, elevational bands or vegetation types. The flexible nature of this methodological innovation can support improved characterization of species distributions for a variety of applications and is being implemented as a standard element underpinning integrative species distribution predictions in the Map of Life (). [ABSTRACT FROM AUTHOR]

Aim Positive relationships between plant species diversity and above-ground productivity have been observed across a wide range of terrestrial ecosystems. Despite a critical contribution of below-ground productivity to overall terrestrial productivity, no consensus exists about the nature of the relationship between species diversity and below-ground productivity. Location Global. Methods We collected data from published studies conducted in natural and planted forests and experimental grassland, crop and pot systems that were purposely implemented to isolate the effects of plant species diversity from other factors, such as soil conditions and topographic features. We conducted meta-analyses of 170 observations for root biomass and 23 observations for root production, derived from 48 published studies, using weighted linear modelling with bootstrap procedures to reconcile the effects of diversity on fine root productivity. Results We found that species mixtures had, on average 28.4% higher fine root biomass and 44.8% higher annual production than monocultures. Higher fine root biomass in species mixtures than in monocultures was consistent across natural forests, planted grasslands, croplands and pot systems, except for young planted forests. Transgressive overyielding was only evident for planted grasslands. The log response ratio of fine root biomass in species mixtures to that in respective monocultures increased with species richness across all ecosystem types, and also increased with experiment age in grasslands. Main conclusions Our meta-analysis reveals positive effects of species diversity on below-ground productivity. Despite profound differences in environments among terrestrial ecosystems, our analysis demonstrated that below-ground productivity responds similarly to variations in species richness. Furthermore, our study also reveals shifts in the effects of diversity over time in both forests and grasslands. Future efforts are needed to further understand below-ground productivity-diversity relationships. [ABSTRACT FROM AUTHOR]

Islands are pieces of land entirely surrounded by sea on which terrestrial and marine organisms live as little as a few metres apart. Yet, in contrast to terrestrial species, marine species have attracted little attention in studies of island theory. The experimental and conceptual origins of this dichotomy date back to the 1970s, although the apposition has softened in the early 2000s, in part a consequence of phylogeographic analyses and the discovery of new marine environments. Here, I explore the possible range of island and island-like settings in the marine realm and find good evidence, albeit in short supply, for integrating marine with terrestrial perspectives during the current transition from equilibrium to general dynamic models of island biogeography. This integration of marine systems into island theory will be facilitated by three advances: (1) development of many descriptive marine studies to reduce the current deficit, (2) design of rigorous comparative studies within and across realms, and (3) modification of conceptual models to unite seemingly disparate situations, for example describing islands in terms of ecological-evolutionary processes. Marine island biogeography is in its infancy; it may present situations that are uncommon in the existing literature, but not rare in nature, and thus contribute substantially to the new dynamic outlook on a half-century-old theme. [ABSTRACT FROM AUTHOR]