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Aim: Amphibians exhibit unusually diverse reproductive modes, including a wide array of parental care strategies. The evolutionary drivers of this diversity, however, remain unclear. Here, we investigate three major factors that might predict interspecific variation in parental care strategies: climate, intrasexual selection and social environment. We hypothesize that some forms of care evolved to cope with harsh conditions, such as dry or unpredictable habitats. We contrast this prediction with the hypothesis that parental roles have co‐evolved with the social environment and mating systems. Location: Global. Major taxa studied: Frogs and toads (Amphibia: Anura). Time period: Extant taxa that represent c. 220 Myr of evolutionary history. Methods: Using geographical and behavioural data for 971 species of frogs and toads that represent 45 anuran families, we quantified the global distribution of four forms of parenting separately for males and females: nest building, nest and/or tadpole attendance, carrying and nourishment. We used phylogenetic comparative analyses to investigate whether climate, social environment and mating systems predicted interspecific variation in parental care. Results: Our results showed that climatic effects contribute to parental care diversity: in cool and humid climates the males provide offspring attendance, whereas in predictable temperatures endotrophy occurs, whereby the female provides all nutrients for the offspring until metamorphosis. In addition, we found other associations between mating systems and forms of parental care: uniparental clutch attendance by males is present in species with territorial defence, whereas cooperative nest building co‐occurs with sperm competition. The type of parental care is not associated with adult sex ratios. Main conclusions: No specific form of care is associated with hostile environments; in fact, some forms of care occur in beneficial conditions, whereas others are used independently from the climate. Instead, parenting diversity has co‐evolved closely with mating systems in frogs. [ABSTRACT FROM AUTHOR]

Aim: Climate variability threatens to destabilize production in many ecosystems. Asynchronous species dynamics may buffer against such variability when a decrease in performance by some species is offset by an increase in performance of others. However, high climatic variability can eliminate species through stochastic extinctions or cause similar stress responses among species that reduce buffering. Local conditions, such as soil nutrients, can also alter production stability directly or by influencing asynchrony. We test these hypotheses using a globally distributed sampling experiment. Location: Grasslands in North America, Europe and Australia. Time period: Annual surveys over 5 year intervals occurring between 2007 and 2014. Major taxa studied: Herbaceous plants. Methods: We sampled annually the per species cover and aboveground community biomass [net primary productivity (NPP)], plus soil chemical properties, in 29 grasslands. We tested how soil conditions, combined with variability in precipitation and temperature, affect species richness, asynchrony and temporal stability of primary productivity. We used bivariate relationships and structural equation modelling to examine proximate and ultimate relationships. Results: Climate variability strongly predicted asynchrony, whereas NPP stability was more related to soil conditions. Species richness was structured by both climate variability and soils and, in turn, increased asynchrony. Variability in temperature and precipitation caused a unimodal asynchrony response, with asynchrony being lowest at low and high climate variability. Climate impacted stability indirectly, through its effect on asynchrony, with stability increasing at higher asynchrony owing to lower inter‐annual variability in NPP. Soil conditions had no detectable effect on asynchrony but increased stability by increasing the mean NPP, especially when soil organic matter was high. Main conclusions: We found globally consistent evidence that climate modulates species asynchrony but that the direct effect on stability is low relative to local soil conditions. Nonetheless, our observed unimodal responses to variability in temperature and precipitation suggest asynchrony thresholds, beyond which there are detectable destabilizing impacts of climate on primary productivity. [ABSTRACT FROM AUTHOR]

Aim: Intraspecific trait variation (ITV) within natural plant communities can be large, influencing local ecological processes and dynamics. Here, we shed light on how ITV in vegetative and floral traits responds to large‐scale abiotic and biotic gradients (i.e., climate and species richness). Specifically, we tested whether associations of ITV with temperature, precipitation and species richness were consistent with any of four hypotheses relating to stress tolerance and competition. Furthermore, we estimated the degree of correlation between ITV in vegetative and floral traits and how they vary along the gradients. Location: Global. Time period: 1975–2016. Major taxa studied: Herbaceous and woody plants. Methods: We compiled a dataset of 18,401 measurements of the absolute extent of ITV (measured as the coefficient of variation) in nine vegetative and seven floral traits from 2,822 herbaceous and woody species at 2,372 locations. Results: Large‐scale associations between ITV and climate were trait specific and more prominent for vegetative traits, especially leaf morphology, than for floral traits. The ITV showed pronounced associations with climate, with lower ITV values in colder areas and higher values in drier areas. The associations of ITV with species richness were inconsistent across traits. Species‐specific associations across gradients were often idiosyncratic, and covariation in ITV was weaker between vegetative and floral traits than within the two trait groups. Main conclusions: Our results show that, depending on the traits considered, ITV either increased or decreased with climate stress and species richness, suggesting that both factors can constrain or enhance ITV, which might foster plant‐population persistence in stressful conditions. Given the species‐specific responses and covariation in ITV, associations can be hard to predict for traits and species not yet studied. We conclude that consideration of ITV can improve our understanding of how plants cope with stressful conditions and environmental change across spatial and biological scales. [ABSTRACT FROM AUTHOR]

Aim: Climate and disturbance alter forest dynamics, from individual trees to biomes and from years to millennia, leaving legacies that vary with local, meso‐ and macroscales. Motivated by recent insights in temperate forests, we argue that temporal and spatial extents equivalent to that of the underlying drivers are necessary to characterize forest dynamics across scales. We focus specifically on characterizing mesoscale forest dynamics because they bridge fine‐scale (local) processes and the continental scale (macrosystems) in ways that are highly relevant for climate change science and ecosystem management. We revisit ecological concepts related to spatial and temporal scales and discuss approaches to gain a better understanding of climate–forest dynamics across scales. Location: Eastern USA. Time period: Last century to present. Major taxa studied: Temperate broadleaf forests. Methods: We review regional literature of past tree mortality studies associated with climate to identify mesoscale climate‐driven disturbance events. Using a dynamic vegetation model, we then simulate how these forests respond to a typical climate‐driven disturbance. Results: By identifying compound disturbance events from both a literature review and simulation modelling, we find that synchronous patterns of drought‐driven mortality at mesoscales have been overlooked within these forests. Main conclusions: As ecologists, land managers and policy‐makers consider the intertwined drivers of climate and disturbance, a focus on spatio‐temporal scales equivalent to those of the drivers will provide insight into long‐term forest change, such as drought impacts. Spatially extensive studies should also have a long temporal scale to provide insight into pathways for forest change, evaluate predictions from dynamic forest models and inform development of global vegetation models. We recommend integrating data collected from spatially well‐replicated networks (e.g., archaeological, historical or palaeoecological data), consisting of centuries‐long, high‐resolution records, with models to characterize better the mesoscale response of forests to climate change in the past and in the future. [ABSTRACT FROM AUTHOR]

Aim: Catastrophic forest mortality due to more extreme rainfall deficits and higher temperatures under future climate scenarios has been predicted. The aim of this study is to explore the magnitude of historical drought‐induced tree mortality under pre‐warming conditions. Location: North‐eastern Australia. Time period: 1845–2017. Major taxa studied: Trees. Methods: Field survey, historical analysis and climate analysis. Results: We present evidence of 18%–30% tree mortality from recent droughts across three regions of north‐eastern Australia with rainfall deficits less severe than earlier historical droughts. The corrected temperature record represents modest warming at the stations with long records in the vicinity of the study areas. In terms of rainfall deficit the most severe drought on record occurred in the early 20th century, and historical evidence confirms that this drought and earlier droughts before the advent of pastoralism coincided with substantial tree mortality. Main conclusions: Dramatic declines in woody biomass in response to drought historically occurred more than once a century and are a natural phenomenon in semi‐arid Australia. The magnitude of drought‐induced tree mortality under natural climate fluctuations requires further investigation in other continents. Widespread drought‐induced tree mortality is not just a recent global change phenomenon and has been underestimated as a natural ecological process. However, even more severe forest die‐off events from more extreme hotter droughts are predicted if Earth's warming proceeds as currently projected. [ABSTRACT FROM AUTHOR]

Aim Nest microclimate is a critical determinant of the survival and development of embryonic and juvenile birds. While abiotic variables such as temperature, precipitation and elevation will influence the conditions experienced by offspring within the nest, parent birds may also exercise some control through nest design and the selection of construction material. The aim of this study is to determine whether avian nest construction and the composition of nest construction material is influenced by geographical variation in climate. In addition, this study aims to address whether the correlation between nest construction and elevation highlighted by other studies is independent of the association between elevation and climate, or if other unmeasured variables are at play. Location Australia Methods We measured the structural and thermal properties of 201 cup-shaped nests, from 36 Australian passerine species, and related these to temperature, precipitation and elevation. Results The rate of heat loss from avian nests is correlated with temperature, precipitation and elevation. Birds that construct nests in cool climates use well-insulating materials irrespective of precipitation, while birds in warm climates use poorly insulating materials when exposed to high rainfall but not when exposed to low rainfall. Main conclusions Local climate influences the construction of nests, through modification of the materials used, and therefore the rate of heat loss from the nest as a whole. In many climates, birds use well-insulating materials; however, birds breeding in warm and wet climates construct their nests with materials that have a higher thermal conductivity. Such nests are possibly less absorptive and able to dry out faster following a rain event, to restore the insulating function of the nest. These findings highlight the importance of studies over large geographical scales for understanding nest construction by birds. [ABSTRACT FROM AUTHOR]