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Mechanistic predictions of ecological niches are fundamentally based on energy and mass exchange processes that, to be realistic, must be linked to microclimate and incorporate behaviour and physiology. Estimates of leaf temperature and associated transpiration and net photosynthesis rates are fundamental in ecology, agriculture and global change biology. Equations for calculating leaf energy budgets have been available for over 60 years and complex models of stomatal behaviour have been developed. However, user‐friendly ways of estimating leaf temperature under realistic microclimatic regimes, including soil moisture effects, remain limited.Here we show that the integrated microclimate and ectotherm functions of the NicheMapR package for the R programming environment can be used to make fast and effective estimates of leaf temperature and associated rates of water loss and photosynthesis for a wide range of leaf functional types, root depths and microhabitats. Stomatal conductance may be constant or simulated to change dynamically (a) as a function of vapour pressure deficit and CO2 concentration, (b) as a function of soil water potential and (c) as a thermoregulatory mechanism to avoid heat stress.We tested the approach against hourly leaf temperature observations in summer from an arid shrubland in Australia, a temperate woodland in Montana USA, along an elevational gradient in Colorado USA, and at a botanical garden in Florida, USA.National or global gridded data sets can provide the required forcing data but local observational data or some combination of local and gridded data can be used. The global ERA5 and NCEP datasets allow historical leaf energy budget calculations to be made anywhere in the world and a Shiny app has been developed to facilitate use of the model with these datasets.Situated leaf energy budget calculations can be used to design informative field programs to collect much needed detailed temporal data on leaf temperature under natural settings, enabling better predictions and interpretations of how plants respond to environmental change. [ABSTRACT FROM AUTHOR]

Aim: The scale of environmental data is often defined by their extent (spatial area, temporal duration) and resolution (grain size, temporal interval). Although describing climate data scale via these terms is appropriate for most meteorological applications, for ecology and biogeography, climate data of the same spatiotemporal resolution and extent may differ in their relevance to an organism. Here, we propose that climate proximity, or how well climate data represent the actual conditions that an organism is exposed to, is more important for ecological realism than the spatiotemporal resolution of the climate data. Location: Temperature comparison in nine countries across four continents; ecological case studies in Alberta (Canada), Sabah (Malaysia) and North Carolina/Tennessee (USA). Time Period: 1960–2018. Major Taxa Studied: Case studies with flies, mosquitoes and salamanders, but concepts relevant to all life on earth. Methods: We compare the accuracy of two macroclimate data sources (ERA5 and WorldClim) and a novel microclimate model (microclimf) in predicting soil temperatures. We then use ERA5, WorldClim and microclimf to drive ecological models in three case studies: temporal (fly phenology), spatial (mosquito thermal suitability) and spatiotemporal (salamander range shifts) ecological responses. Results: For predicting soil temperatures, microclimf had 24.9% and 16.4% lower absolute bias than ERA5 and WorldClim respectively. Across the case studies, we find that increasing proximity (from macroclimate to microclimate) yields a 247% improvement in performance of ecological models on average, compared to 18% and 9% improvements from increasing spatial resolution 20‐fold, and temporal resolution 30‐fold respectively. Main Conclusions: We propose that increasing climate proximity, even if at the sacrifice of finer climate spatiotemporal resolution, may improve ecological predictions. We emphasize biophysically informed approaches, rather than generic formulations, when quantifying ecoclimatic relationships. Redefining the scale of climate through the lens of the organism itself helps reveal mechanisms underlying how climate shapes ecological systems. [ABSTRACT FROM AUTHOR]

An understanding of how biodiversity is distributed across the broad spatial scales can resolve pure questions about ecological and historical processes and solve applied problems in conservation planning. Invertebrates such as insects make up much of biodiversity yet are rarely a focus in studies of regional‐scale diversity patterns, partly due to data deficiency.We took advantage of historical field notebooks to investigate the richness and compositional pattern of grasshoppers across a vast area of Australia (Western Australia, 2.6 million km2). We extracted grasshopper occurrence records from historical surveys of 1328 locations spanning 1947 to 1985. We developed generalised dissimilarity models to identify species compositional turnover across families and modelled species richness with regression analyses.Species composition was most distinct in mesic south‐west, north and north‐west regions and was most uniform through the arid interior region with the exception of the topographically complex Pilbara region. Species richness was highest in the arid interior and north and lowest in the cool and wet south‐west.The patterns of grasshopper species diversity and endemism were like patterns previously reported for lizards and this may reflect their common independence from water and their phylogenetic bias towards warm environments.Although high species richness was predicted in the Pilbara region, the area remains underrepresented in the national reserve system, with <10% of its area protected. High levels of short‐range endemism were found in general, with only ~1/4 of short‐range endemics being located in the national reserve system.Our analyses demonstrate that field notebooks can be a valuable resource for biogeographic analyses and for planning invertebrate conservation. [ABSTRACT FROM AUTHOR]

This article discusses the impact of climate change on human heat stress and the limitations of using the wet-bulb temperature as an index of heat stress. The wet-bulb temperature is often used in various indices to predict human heat stress, but it underestimates the impact of climate change on human thermoregulation, especially at lower humidity. The article highlights the importance of considering factors such as air movement and boundary layers in accurately quantifying heat exchange. The authors suggest using more complex models that take into account multiple variables to better predict human responses to heat stress. [Extracted from the article]

Population translocations are used increasingly as a conservation strategy for vertebrates. However, relatively few attempts have been made to translocate invertebrates despite their potential benefits for food webs, and despite the practicality of undertaking such translocations in small areas including urban environments where space is limited.We conducted 36 translocations of 1851 individuals of the generalist flightless grasshopper Vandiemenella viatica across urban Melbourne, where 93% of its original habitat has been lost.We aimed to understand characteristics essential for grasshopper persistence and to investigate detection, occupancy, dispersal and habitat suitability throughout its active period to improve insect translocation success in urban settings using revegetated sites and small remnant habitats. We also measured movement and detection probability after one week in short‐term trials.The one‐week trial indicated that grasshopper sex and colour morph did not influence the probability of detection, and there was no evidence of directional movement by females and males.One year after translocation, V. viatica were found in 28 out of 36 translocation sites. These surveys showed that detection probability changed across survey seasons and was influenced by soil temperature. Also, soil temperature positively affected detection in the winter surveys. Occupancy probability was influenced by graminoid cover, plant species richness and weed cover. We found no evidence of directional movement by females and males in the F1 generation. Abundance and presence/absence data were best explained by graminoid cover and plant species richness.Our findings suggest that wingless grasshopper translocations are feasible in small urban patches of suitable habitat, helping to restore invertebrate biodiversity and ecological services. [ABSTRACT FROM AUTHOR]

Translocation is an increasingly used tool in conservation management, but there is a risk that source populations are overcollected. The risk depends critically on the detection probability and the source population size. We quantified this risk for a wingless grasshopper population in a patch of remnant habitat in suburban Melbourne that was condemned to be cleared for housing development. We collected ∼2000 grasshoppers in five samples spread over 1 month and used the results to estimate the initial population size (∼3400) with high confidence. Despite our perception of substantially depleting the population, we removed only an estimated 60%, and this relatively high fecundity (∼50 eggs per lifetime) annual species had recovered by the following year to near its original density. Wild‐to‐wild translocation is likely to be a low‐cost and effective strategy in the conservation of many invertebrates, and our findings highlight the feasibility of using natural source populations. [ABSTRACT FROM AUTHOR]

Low‐vagility species may hold strong genetic signatures of past biogeographical processes but are also vulnerable to habitat loss. Flightless grasshoppers of the morabine group were once widespread in southeastern Australia, including Tasmania, but are becoming restricted to remnant patches of vegetation, with local ranges impacted by agriculture and development as well as management. Habitat fragmentation can generate genetically differentiated "island" populations with low genetic variation. However, following revegetation, populations could be re‐established, and gene flow increased. Here we characterize single nucleotide polymorphism‐based genetic variation in a widespread chromosomal race of the morabine Vandiemenella viatica (race 19) to investigate the genetic health of remnant populations and to provide guidelines for restoration efforts. We update the distribution of this race to new sites in Victoria and Tasmania, and show that V. viatica populations from northern Tasmania and eastern Victoria have reduced genetic variation compared to other mainland populations. In contrast, there was no effect of habitat fragment size on genetic variation. Tasmanian V. viatica populations fell into two groups, one connected genetically to eastern Victoria and the other connected to southwestern Victoria. Mainland populations showed isolation by distance. These patterns are consistent with expectations from past biogeographical processes rather than local recent population fragmentation and emphasize the importance of small local reserves in preserving genetic variation. The study highlights how genomic analyses can combine information on genetic variability and population structure to identify biogeographical patterns within a species, which in turn can inform decisions on potential source populations for translocations. [ABSTRACT FROM AUTHOR]

Most ecological analyses and forecasts use weather station data or coarse interpolated, gridded air temperature data. Yet, these products often poorly capture the microclimates experienced by organisms that respond to fine‐scale spatial and temporal environmental variation near the surface. Sources of historic and projected future data with finer spatial and temporal resolution are proliferating. We qualitatively and quantitatively review and evaluate the available data on three core issues central to microclimate modeling: the quality of the input environmental data, the ability of algorithms to capture microclimatic processes given environmental forcing data, and how best to access microclimatic data. We show how differences between observed environmental conditions and those estimated using environmental forcing data, microclimate algorithms, and precomputed microclimate datasets can be substantial depending on the variable, location, and season. The choice of environmental dataset to parameterize biophysical models has ramifications for biological estimates, such as the duration of potential activity and incidence of thermal stress. New data sources offering high temporal and spatial resolution correspond well to observational data and have the potential to revolutionize understanding of the ecological implications of microclimate variability. We provide resources to help users select and access appropriate environmental data for biological applications, including users' guides and interactive visualization, to better infer how organisms experience climate variability and change. [ABSTRACT FROM AUTHOR]

This project discerns an early cybernetic paradigm for the internet in the worldwide movement towards uninterrupted motor travel that developed in the first half of the twentieth century. Freeway designers, especially in Germany and the United States, pursued utopias of control over nature, independence from the topography of a particular locale and unrestricted transportation on a national scale. As a physical analogue of the digital landscape that would follow it, the execution of the Eisenhower Interstate System prioritized modern technological values in real space that went on to guide the design of virtual space. Moreover, in recent years physical and virtual transportation networks have become even more closely linked through location-based social navigation technologies such as Waze and Google Maps. Located at the intersection, or rather at the interchange, of media ecology and urban communication, this project seeks to illuminate the utopias of design that guide real and virtual space in the era of the interstate and the internet, with ramifications for those who seek to navigate them thoughtfully in the twenty-first century. [ABSTRACT FROM AUTHOR]

The baseline distribution data for all species of a given group in a region can provide fundamental insights into biogeographic questions about historic patterns of species richness, population trends and extinction. Grasshoppers are one major group of insects for which a continent‐wide perspective on their geographic distribution can be obtained. This is because they were extensively surveyed in Australia for 54 years (1936–1989) as part of Commonwealth expeditions to obtain specimens for the Australian National Insect Collection (ANIC). Field notebooks recorded from those surveys, under the direction of ANIC curator and director K. H. L. Key, form the principal source of historic distribution records for grasshoppers in Australia. We digitised all the 223 notebooks (2486 pages) and transcribed all the field trips conducted in Western Australia (WA) and Tasmania (47 notebooks, 590 pages). We then carefully geocoded all sampling sites of the transcribed notebooks, following the odometer readings and descriptions of routes from a suitable reference point using historic topographic maps and Google Earth. In total, we extracted 8975 geographic coordinates for 477 species having a confirmed or putative taxonomic name at genus or species level (only 170 of these species have been formally described). We found that species richness varied spatially, with highest richness in arid interior and north of WA. Historic grasshopper surveys were non‐randomly distributed across both WA and Tasmania with the highest survey intensity around coastal regions. Variation was observed among surveyors in terms of the number of species detected per site, between‐site distance and the season of survey being conducted. Overall, however, the dataset is among the most comprehensive continent‐wide surveys of Australian invertebrates and will greatly facilitate future work on their ecology, biogeography, conservation and responses to environmental change. [ABSTRACT FROM AUTHOR]

Eggs are a vulnerable stage because they are sensitive to thermal and hydric conditions and yet cannot behaviourally avoid stressful environments. A general mechanistic model of egg development in natural nests requires microclimatic predictions of temperature, humidity, radiation (if above ground) and water potential (if buried in soil) to be integrated with models of heat and water exchange of the egg and the metabolism of the developmental process. Although all the required pieces for such a model now exist, they have not been integrated into a general modelling framework.We developed such an integration using NicheMapR package for mechanistic niche modelling. Specifically, we took an existing general model of egg water exchange and connected it with the microclimate model in NicheMapR to simulate nest thermal and hydric environments, including the effects of soil water potential on liquid and vapour exchange and moisture‐mediated soil thermal conductivity on heat exchange. We then used the Dynamic Energy Budget model within the ectotherm model of NicheMapR as the mechanistic engine for the developmental process, allowing the explicit computation of the dynamics of metabolic heat production and all aspects of mass exchange.We illustrate the modelling framework using existing laboratory and field data on reptiles, insects, and birds. We show that it can capture laboratory observations of water exchange and metabolic heat production and how it can be used to map potential development and water uptake under natural conditions at the continental scale.The modelling framework can be used to interpret laboratory experiments and allows strong inferences to be made about the abiotic constraints on egg development in natural nests under past, present, and future environmental change. [ABSTRACT FROM AUTHOR]

Many threatened species depend on climatic microrefugia, but places with harsh climates for predators may also play a refugial role. Feral cats threaten many native species in arid Australia. Although cats can persist in regions with no free water, their abundance should depend on the availability of microclimates that protect them from harsh environmental conditions. We developed a biophysical model of feral cat heat stress and used it to explore how behavior and microhabitat features influence water requirements and activity. Tests of model predictions against fine‐scale GPS and microclimate data highlight the importance of refuges, particularly rabbit burrows. Continent‐wide simulations show large but temporally varying areas of the arid zone that would be lethal for cats without access to deep or shaded burrows. Our approach can identify locations that may act as natural refuges for native prey, and where habitat management strategies may be effective in controlling cat abundance. [ABSTRACT FROM AUTHOR]

Microclimate models predict temperature and other meteorological variables at scales relevant to individual organisms. The broad application of microclimate models requires gridded macroclimatic variables as input. However, the spatial and temporal resolution of such inputs can be a limiting factor on the accuracy of microclimate predictions. Due to its fine resolution and accuracy, the ERA5 reanalysis dataset is emerging as the favoured resource for global historical weather and climate data and has great potential for aiding microclimate modelling.Here we describe mcera5, an R language package that provides convenient access to, and wrangling of, the ERA5 climate datasets for use in microclimate models. Through this package, we provide functions to query ERA5 data for desired spatial and temporal extents, to correct for spatial biases and process outputs for easy interpretation by ecologists, thereby allowing faster and more accurate microclimate predictions.By validating with empirical observations from multiple biomes globally, we demonstrate that the use of ERA5 climate forcing via mcera5 improves the prediction accuracy of soil moisture, air temperature and relative humidity as compared to forcing with other globally available data and offers comparable performance when predicting soil temperatures.Through the provision of fine‐resolution ERA5 data, the mcera5 package fits into an ecosystem of tools for modelling microclimate in a spatio‐temporally explicit fashion, advancing our ability to efficiently predict microclimate for any place on Earth for the past, present or future. The package also provides convenient access to ERA5 datasets for a range of other applications. [ABSTRACT FROM AUTHOR]

The possible role of climate change in late Quaternary animal extinctions is hotly debated, yet few studies have investigated its direct effects on animal physiology to assess whether past climate changes might have had significant impacts on now‐extinct species. Here we test whether climate change could have imposed physiological stress on the Tasmanian devil Sarcophilus harrisii during the mid‐Holocene, when the species went extinct on mainland Australia. Physiological values for the devil were quantified using mechanistic niche models of energy and water requirements for thermoregulation, and soil‐moisture‐based indices of plant stress from drought to indirectly represent food and water availability. The spatial pervasiveness, extremity and frequency of physiological stresses were compared between a period of known climatic and presumed demographic stability (8000–6010 BP) and the extinction period (5000–3010 BP). We found no evidence of widespread negative effects of climate on physiological parameters for the devil on the mainland during its extinction window. This leaves cultural and demographic changes in the human population or competition from the dingo Canis dingo as the main contending hypotheses to explain mainland loss of the devil in the mid‐Holocene. [ABSTRACT FROM AUTHOR]

Aim: Our understanding of species' responses to climate depends on choosing the scale for the analysis. Processes driving physiological adaptation that occur at the small spatial scales most relevant to animals may be masked in correlations between organismal traits and broad‐scale climatologies, but the extent to which this undermines our understanding of the macroevolution of physiological traits is unknown. Location: Global. Time period: Current. Major taxa studied: Lizards. Methods: We investigated relationships between physiological traits (water loss rate, standard and field metabolic rates, thermal preferences and critical thermal limits) and environmental conditions in 369 lizard species across sets of environmental predictors representing different processes across hierarchically nested spatial scales: macroclimate, microclimate and biophysical. Results: We found that microclimatic and biophysical predictors had greater explanatory power than macroclimatic predictors for all traits except standard and field metabolic rates. Across spatial scales, standard metabolic rate was negatively related to maximum temperatures whereas field metabolic rate was positively related to minimum temperatures. Thermal preference and critical limits showed expected relationships with environmental temperature, but preferred temperature and critical thermal maxima were most strongly associated with soil water potential, as was evaporative water loss. Main conclusions: The use of proximal environmental predictors, via the principles of microclimatic and biophysical modelling, can be more informative in comparative physiological analyses than the more traditional application of macroclimatic data. In our study it led us to new, testable hypotheses about the role of habitat structure mediated by soil moisture. New datasets and computational methods mean that proximal environmental predictors can be readily computed for any kind of organism and their application to comparative studies should improve our understanding of physiological evolution. [ABSTRACT FROM AUTHOR]

As professor of Greek and theology at the University of Wittenberg, Philip Melanchthon (1497-1560) authored three of the most important rhetorical textbooks of his era. Melanchthon's addition of a new genre of rhetoric, the didactic, to the classical genres of demonstrative, judicial, and deliberative oratory illuminates his view of rhetoric as an instrument for the renaissance and reformation of traditions and institutions. Cultivating faculties of judgment and understanding was Melanchthon's prescription for survival amid theological and political chaos--a prescription that continues to hold value for rhetors in the current historical moment. [ABSTRACT FROM AUTHOR]

Endothermic organisms typically maintain high and relatively constant body temperatures in the face of environmental variation by regulating their metabolic and water loss rates in conjunction with behavioural and postural adjustments. A mechanistic understanding of these processes provides a perspective of the fundamental niches of endotherms by quantifying their energy and water requirements, restrictions on habitat use and survival limits. Here we introduce and document the endotherm model of NicheMapR, an R package that includes a suite of programs for the mechanistic modelling of energy and mass exchange between organisms and their environments. The NicheMapR endotherm model is based on a Fortran program that simultaneously solves for the metabolic rate, water loss rate, fur/feather temperature and skin temperature required to balance the heat budget in a given microclimate. These calculations are a function of traits relating to insulation, shape, physiological and behavioural responses. The program contains algorithms for computing heat transfer through a porous insulative layer (fur/feathers), including solar and infrared radiation fluxes as well as convective and conductive exchange, and can handle differing dorsal and ventral traits and environments. Here we configure the program to be called from R as part of the NicheMapR package and describe the model in detail. We break the program into a set of modules that can be run in isolation, or jointly, and combined in different ways to capture species‐specific thermoregulatory responses. We explain the theory and underlying subroutines, and the default thermoregulatory settings. We discuss how the model can be adapted to incorporate species‐specific behaviours and extended to incorporate multiple body parts. We also compare the endotherm modelling setup with the ectotherm model of the NicheMapR package and discuss how the different modelling strategies they require reflect fundamental biological issues. [ABSTRACT FROM AUTHOR]

The use of traits is growing in ecology and biodiversity informatics, with initiatives to collate trait data and integrate it into biodiversity databases. A need to develop better predictive capacity for how species respond to environmental change has in part motivated this focus. Functional traits are of most interest—those with a defined link to individual survival, development, growth and reproduction.Non‐trivial challenges arise immediately in deciding which functional traits to prioritise and how to characterise them. Here we discuss the advantages of a theoretical perspective for defining functional traits in the context of dynamical systems models of energy and mass exchange that link organisms to their environments. We argue that the theoretical frameworks upon which such models are built (biophysical ecology, metabolic theory) provide clear criteria to decide upon functional trait definitions, measurement requirements and associated metadata, via their mathematical connection to model parameters and state variables, and thus to system performance (survival, development, growth and reproduction).We distinguish 'descriptive' traits from 'functional' traits by dividing the latter into four classes—parameter, model, threshold and estimation—according to whether they are model parameters, define model structure, are threshold state variables or can be used to estimate model parameters.We develop a decision tree for this classification and illustrate it in the context of mammalian heat exchange but emphasise the scheme's generality to any kind of organism.We show how a theoretical perspective may change how we prioritise traits for collection and databasing in ways that are not necessarily more difficult to achieve, especially with new technologies, and provide clear guidance for requisite metadata. The use of theoretically driven criteria for prioritising the collection of functional trait data will maximise the generality, quality and consistency of trait databases for comparative analyses. Such databases will simultaneously facilitate the development of integrated predictive modelling frameworks across multiple organisational scales from individuals to ecosystems. ​ A free Plain Language Summary can be found within the Supporting Information of this article. [ABSTRACT FROM AUTHOR]

All terrestrial ectotherms are constrained to some degree by their thermal environment and the extent to which they can behaviorally buffer variable thermal conditions. New biophysical modeling methods (NicheMapR) allow the calculation of the body temperature of thermoregulating animals anywhere in the world from first principles, but require detailed observational data for parameterization and testing. Here we describe the thermoregulatory biology of marching bands of the desert locust, Schistocerca gregaria, in the Sahara Desert of Mauritania where extreme heat and strong diurnal fluctuations are a major constraint on activity and physiological processes. Using a thermal infrared camera in the field, we showed that gregarious nymphs altered the microhabitats they used, as well as postural thermoregulatory behaviors, to maintain relatively high body temperature (nearly 40°C). Field and laboratory experiments demonstrated that the preferred body temperature accelerated digestive rates. Migratory bands frequently left foraging sites with full guts before consuming all vegetation and moved to another habitat before emptying their foregut. Thus, the repertoire for behavioral thermoregulation in the desert locust strongly facilitates foraging and digestion rates, which may accelerate developmental rates and increase survival. We used our data to successfully parameterize a general biophysical model of thermoregulatory behavior that could capture hourly body temperature and activity at our remote site using globally available environmental forcing data. This modeling approach provides a stronger basis for forecasting thermal constraints on locust outbreaks under current and future climates. [ABSTRACT FROM AUTHOR]

Conservation research is dominated by vertebrate examples but the shorter generation times and high local population sizes of invertebrates may lead to very different management strategies, particularly for species with low movement rates. Here we investigate the genetic structure of an endangered flightless grasshopper, Keyacris scurra, which was used in classical evolutionary studies in the 1960s. It had a wide distribution across New South Wales (NSW) and Victoria in pre‐European times but has now become threatened because of land clearing for agriculture and other activities. We revisited remnant sites of K. scurra, with populations now restricted to only one area in Victoria and a few small patches in NSW and the Australian Capital Territory (ACT). Using DArtseq to generate SNP markers as well as mtDNA sequence data, we show that the remaining Victorian populations in an isolated valley are genetically distinct from the NSW populations and that all populations tend to be genetically unique, with large FST values up to 0.8 being detected for the SNP datasets. We also find that, with one notable exception, the NSW/ACT populations separate genetically into previously described chromosomal races (2n = 15 vs. 2n = 17). Isolation by distance was detected across both the SNP and mtDNA datasets, and there was substantial differentiation within chromosomal races. Genetic diversity as measured by heterozygosity was not correlated with the size of remaining habitat where the populations were found, with high variation present in some remnant cemetery sites. However, inbreeding correlated negatively with estimated habitat size at 25–500 m patch radius. These findings emphasize the importance of small habitat areas in conserving genetic variation in such species with low mobility, and they highlight populations suitable for future translocation efforts. [ABSTRACT FROM AUTHOR]

Metabolic theory aims to tackle ecological and evolutionary problems by explicitly including physical principles of energy and mass exchange, thereby increasing generality and deductive power. Individual growth models (IGMs) are the fundamental basis of metabolic theory because they represent the organisational level at which energy and mass exchange processes are most tightly integrated and from which scaling patterns emerge. Unfortunately, IGMs remain a topic of great confusion and controversy about the origins of the ideas, their domain and breadth of application, their logical consistency and whether they can sufficiently capture reality. It is now 100 years since the first theoretical model of individual growth was put forward by Pütter. His insights were deep, but his model ended up being attributed to von Bertalanffy and his ideas largely forgotten. Here I review Pütter's ideas and trace their influence on existing theoretical models for growth and other aspects of metabolism, including those of von Bertalanffy, the Dynamic Energy Budget (DEB) theory, the Gill‐Oxygen Limitation Theory (GOLT) and the Ontogenetic Growth Model (OGM). I show that the von Bertalanffy and GOLT models are minor modifications of Pütter's original model. I then synthesise, compare and critique the ideas of the two most‐developed theories, DEB theory and the OGM, in relation to Pütter's original ideas. I formulate the Pütter, DEB and OGM models in the same structure and with the same notation to illustrate the major similarities and differences among them. I trace the confusion and controversy regarding these theories to the notions of anabolism, catabolism, assimilation and maintenance, the connections to respiration rate, and the number of parameters and state variables their models require. The OGM model has significant inconsistencies that stem from the interpretation of growth as the difference between anabolism and maintenance, and these issues seriously challenge its ability to incorporate development, reproduction and assimilation. The DEB theory is a direct extension of Pütter's ideas but with growth being the difference between assimilation and maintenance rather than anabolism and catabolism. The DEB theory makes the dynamics of Pütter's 'nutritive material' explicit as well as extending the scheme to include reproduction and development. I discuss how these three major theories for individual growth have been used to explain 'macrometabolic' patterns including the scaling of respiration, the temperature–size rule (first modelled by Pütter), and the connection to life history. Future research on the connections between theory and data in these macrometabolic topics have the greatest potential to advance the status of metabolic theory and its value for pure and applied problems in ecology and evolution. [ABSTRACT FROM AUTHOR]

Body size affects the body temperature of an ectotherm by altering both heating rates and the microclimate experienced. These joint effects are rarely considered in the analyses of climatic constraints on ectotherms but nonetheless influence body temperatures and thus activity periods and foraging opportunities.Here we develop and test transient heat‐budget models that use height‐specific microclimatic forcing to compute the dynamics of size‐dependent body temperatures of ectotherms in sun and in shade. We incorporate a model of behavioural thermoregulation and use it to compute potential body temperatures and then to map these to ecologically relevant indices, including foraging opportunities and thermal constraints. To illustrate potential applications, we combine a microclimate model driven by a global climate database with the transient behavioural algorithm developed for lizards to explore how body size (10 and 1,000 g) and size‐specific microclimate (at natural heights of 1 and 7.5 cm, respectively) interactively influence body temperatures and ecological indices at a warm, arid location in Australia in both spring and summer. To explore microclimatic effects, we contrast temperatures and indices for animals positioned at their natural versus reciprocal heights above the ground.Our simulations show that the behavioural and ecological consequences of size can be strongly biased when joint effects of body size and size‐imposed microclimate are ignored. For example, the two body sizes did not differ in total foraging time when compared at their natural heights, but did differ if compared at the same height, the direction of this difference reversing with the height at which they were compared. We show how computed foraging times can be translated to potential foraging radii from a central place (burrow or shade‐providing bush), thereby illustrating how body size can be physiologically translated into habitat connectivity as a function of different shade configurations, for example, as modified by fire regimes or shrub dieback.All functions are now integrated into the biophysical modelling r package NicheMapR and as a Shiny app, which should provide new insights and avenues for investigation into functional interactions between body size and habitat structure for ectotherms. [ABSTRACT FROM AUTHOR]

Recent reports of insect declines across Europe and other parts of the world have emphasised the generally poor baseline that exists for assessing changes in biodiversity. One important source of untapped baseline distribution data is field notebooks, which are often associated with the collection activities of museums and other scientific institutions and may be decades or even centuries old. Over 220 field notebooks are associated with the grasshopper (Caelifera) collection in the Australian National Insect Collection, containing detailed notes on the times and places species were collected as well as vegetation and soil descriptions. In 2019, we resurveyed 45 locations from three of these notebooks from the 1940s, to assess the potential value of larger‐scale efforts in the future. We found substantial differences in grasshopper species richness and composition between the surveys; richness was generally higher in our survey, and some species showed dramatic increases in range and occurrence, whereas others remained relatively static. There was also evidence for vegetation state transitions in some areas, including increased weediness and shrub thickening, which may be associated with changes in the grasshopper fauna. We developed approaches for comparing environmental conditions across surveys and found that our species richness and abundance estimates were positively correlated with rainfall in the year preceding each survey. We conclude that further resurvey work on these field notebooks will provide a strong baseline picture of the diversity, distribution and abundance of the Australian grasshopper fauna for assessments of future change and may also give new insights about associated vegetation changes. [ABSTRACT FROM AUTHOR]

In cold environments ectotherms can be dormant underground for long periods. In 1941 Cowles proposed an ecological trade‐off involving the depth at which ectotherms overwintered: on warm days, only shallow reptiles could detect warming soils and become active; but on cold days, they risked freezing. Cowles discovered that most reptiles at a desert site overwintered at shallow depths. To extend his study, we compiled hourly soil temperatures (5 depths, 90 sites, continental USA) and physiological data, and simulated consequences of overwintering at fixed depths. In warm localities shallow ectotherms have lowest energy costs and largest reserves in spring, but in cold localities, they risk freezing. Ectotherms shifting hourly to the coldest depth potentially reduce energy expenses, but paradoxically sometimes have higher expenses than those at fixed depths. Biophysical simulations for a desert site predict that shallow ectotherms have increased opportunities for mid‐winter activity but need to move deep to digest captured food. Our simulations generate testable predictions to eco‐physiological questions but rely on physiological responses to acute cold rather than to natural cooling profiles. Furthermore, natural‐history data to test most predictions do not exist. Thus, our simulation approach uncovers knowledge gaps and suggests research agendas for studying ectotherms overwintering underground. [ABSTRACT FROM AUTHOR]

Winter climate warming is rapidly leading to changes in snow depth and soil temperatures across mid‐ and high‐latitude ecosystems, with important implications for survival and distribution of species that overwinter beneath the snow. Amphibians are a particularly vulnerable group to winter climate change because of the tight coupling between their body temperature and metabolic rate. Here, we used a mechanistic microclimate model coupled to an animal biophysics model to predict the spatially explicit effects of future climate change on the wintering energetics of a freeze‐tolerant amphibian, the Wood Frog (Lithobates sylvaticus), across its distributional range in the eastern United States. Our below‐the‐snow microclimate simulations were driven by dynamically downscaled climate projections from a regional climate model coupled to a one‐dimensional model of the Laurentian Great Lakes. We found that warming soil temperatures and decreasing winter length have opposing effects on Wood Frog winter energy requirements, leading to geographically heterogeneous implications for Wood Frogs. While energy expenditures and peak body ice content were predicted to decline in Wood Frogs across most of our study region, we identified an area of heightened energetic risk in the northwestern part of the Great Lakes region where energy requirements were predicted to increase. Because Wood Frogs rely on body stores acquired in fall to fuel winter survival and spring breeding, increased winter energy requirements have the potential to impact local survival and reproduction. Given the geographically variable and intertwined drivers of future under‐snow conditions (e.g., declining snow depths, rising air temperatures, shortening winters), spatially explicit assessments of species energetics and risk will be important to understanding the vulnerability of subnivium‐adapted species. [ABSTRACT FROM AUTHOR]

Inefficiencies in monitoring programs waste resources. Ideally, we would predict when and where target species are most detectable and place our effort accordingly. Statistical models can generate predictor functions relating survey conditions to detectability but are phenomenological; they do not incorporate biological constraints and so using them to predict into unsampled time and space is risky. Biophysical ecology allows us to place constraints on detection by identifying abiotic conditions in which the target species cannot be present. We show how such constraint can be incorporated into standard detection models. We use the striped legless lizard (Delma impar), a threatened cryptic species, in southeastern Australia, as a case study, using fortnightly monitoring data collected between June 2016 to May 2017. These lizards are monitored by searching under tiles placed in arrays; we used a biophysical model to simulate the thermal microclimate under tiles and combined this with the striped legless lizard's thermal physiology to predict when tiles could be used. When compared against a large monitoring dataset, lizards were rarely observed at times the model predicted they should not be present, but the model also over‐predicted presences. A statistical occupancy model showed that much of this over‐prediction is explained by a generally low detection probability, and a seasonal trend in detection beyond that captured in the biophysical model. We then replaced the temperature covariates of detection in the statistical model with our biophysical prediction (a categorical variable). The resulting model explained almost the same amount of variance in detections as the original model but using a single variable that captured biological constraints. The biophysical model allowed us to place mechanistic constraints on detection, but it still needed to be informed by observed aspects of the species' behavior that were not influenced by temperature. Hybrid statistical‐biophysical models such as ours offer a powerful tool for forecasting optimal survey conditions for a wide array of species. © 2020 The Wildlife Society. We compare biophysical and statistical detection models using data on a threatened legless lizard. We show that using biophysical predictions as inputs to the statistical model generates robust forecasts of detection probability. [ABSTRACT FROM AUTHOR]

The vulnerability of species to climate change is jointly influenced by geographic phenotypic variation, acclimation and behavioural thermoregulation. The importance of interactions between these factors, however, remains poorly understood.We demonstrate how advances in mechanistic niche modelling can be used to integrate and assess the influence of these sources of uncertainty in forecasts of climate change impacts.We explored geographic variation in thermal tolerance (i.e. maximum and minimum thermal limits) and its potential for acclimation in juvenile European common frogs Rana temporaria along elevational gradients. Furthermore, we employed a mechanistic niche model (NicheMapR) to assess the relative contributions of phenotypic variation, acclimation and thermoregulation in determining the impacts of climate change on thermal safety margins and activity windows.Our analyses revealed that high-elevation populations had slightly wider tolerance ranges driven by increases in heat tolerance but lower potential for acclimation. Plausibly, wider thermal fluctuations at high elevations favour more tolerant but less plastic phenotypes, thus reducing the risk of encountering stressful temperatures during unpredictable extreme events. Biophysical models of thermal exposure indicated that observed phenotypic and plastic differences provide limited protection from changing climates. Indeed, the risk of reaching body temperatures beyond the species' thermal tolerance range was similar across elevations. In contrast, the ability to seek cooler retreat sites through behavioural adjustments played an essential role in buffering populations from thermal extremes predicted under climate change. Predicted climate change also altered current activity windows, but high‐elevation populations were predicted to remain more temporally constrained than lowland populations.Our results demonstrate that elevational variation in thermal tolerances and acclimation capacity might be insufficient to buffer temperate amphibians from predicted climate change; instead, behavioural thermoregulation may be the only effective mechanism to avoid thermal stress under future climates. [ABSTRACT FROM AUTHOR]

An extended illustration from Merleau-Ponty's Phenomenology of Perception describes the interplay of habit, sedimentation, and intersubjectivity in the practice and performance of a skilled organist. This paper takes up Merleau-Ponty's example in order to describe some of the phenomenological characteristics of embodied musical performance. These characteristics point toward an intersubjective event of "consecration," as Merleau-Ponty describes it, in which the musician adopts the role of rhetor, inviting the audience into a shared dwelling place. [ABSTRACT FROM AUTHOR]

Aim: The aim was to test the capacity of an ecologically focused microclimate model to capture the interaction between snow cover and soil temperature and use it to assess how historical and future climate warming affects exposure of organisms to stressfully cold conditions in shallow soil. Location: Continental USA. Time period: 1980–2017. Methods: A snow heat budget algorithm was developed and integrated with the general‐purpose microclimate model of the NicheMapR package. The gridMET daily historical weather grids were used as environmental forcing. The model was tested against hourly observations of soil temperature and snow cover for 590 Soil Climate Analysis Network/SNOw TELemetry sites across the USA. It was then used to simulate cold stress exposure of ectotherms and hibernation costs for endotherms. Results: The model captured soil and snow observations to within c. 10%–15% of the range (r c. near 0.85). Air temperature exhibited a mean warming rate of 0.37°C per decade across sites, but in snow‐affected regions the predicted shallow‐soil warming rates were one‐third lower. Biophysical analyses predicted an increase in the activity time of ectotherms as a result of contemporary climate change but little change in cold stress at most sites. For endotherms, hibernation costs were predicted to decline in general. However, both reduced and increased cold stress was simulated to occur for ectotherms and endotherms under simulated air temperature warming of ≤3 °C. Main conclusions: Many of the direct biological consequences of climate warming will be mediated through soil temperature. Microclimatic processes linked to snow cover mean that exposure to cold stress for both ectotherms and endotherms might stay constant, decrease or even increase under climate warming, depending on the local circumstances and species‐specific biology. The idiosyncratic and season‐specific decoupling of above‐ and below‐ground environments under climate warming will have important ecological consequences in snow‐affected regions and can now be computed mechanistically. [ABSTRACT FROM AUTHOR]

The structure of tubular transport networks is thought to underlie much of biological regularity, from individuals to ecosystems. A core assumption of transport network models is either area-preserving or area-increasing branching, such that the summed cross-sectional area of all child branches is equal to or greater than the cross-sectional area of their respective parent branch. For insects, the most diverse group of animals, the assumption of area-preserving branching of tracheae is, however, based on measurements of a single individual and an assumption of gas exchange by diffusion. Here we show that ants exhibit neither area-preserving nor area-increasing branching in their abdominal tracheal systems. We find for 20 species of ants that the sum of child tracheal cross-sectional areas is typically less than that of the parent branch (area-decreasing). The radius, rather than the area, of the parent branch is conserved across the sum of child branches. Interpretation of the tracheal system as one optimized for the release of carbon dioxide, while readily catering to oxygen demand, explains the branching pattern. Our results, together with widespread demonstration that gas exchange in insects includes, and is often dominated by, convection, indicate that for generality, network transport models must include consideration of systems with different architectures. Author summary: A fundamental assumption of models of the transport of substances through networks of tubes, such as circulatory systems in animals and vascular systems in plants, is that the total cross-sectional area of the tubes remains constant irrespective of the branching level, or that it increases slightly in the direction from the largest to the smallest tubes. One large tube should have the same or a slightly smaller area than the sum of the next two tubes after a branching. The assumption of such a pattern underpins one of biology's most influential ideas–the metabolic theory of ecology. Surprisingly, the assumption has never been systematically examined for insects–the planet's most diverse group of animals which deliver oxygen to and remove carbon monoxide from their bodies using a network of tubes known as tracheae. Until recently, it has been technologically very challenging to do so. Here, we use x-ray synchrotron tomography to overcome this challenge. We show that tracheal branching in 20 species of ants does not follow this pattern. Rather, cross-sectional area reduces in an inwards direction. We then use modelling to show that such a pattern facilitates outward CO2 release, a process more challenging for insects than moving oxygen inwards. Our work suggests that much still needs to be done to understand the fundamental assumptions underlying network transport models and how they apply more generally across life–especially in the context of why metabolic rate scales with body size. [ABSTRACT FROM AUTHOR]

Mechanistic niche models characterise the fundamental niche of an organism by determining thermodynamic constraints on its heat, water and nutritional budget, and the consequences of this for growth, development and reproduction. They can thus quantify constraints on survival, activity and, ultimately, the vital rates that determine population growth, given a sequence of environmental conditions and the key morphological, physiological and behavioural functional traits. Here we introduce and document the ectotherm model of NicheMapR, an R package that includes a suite of programs for the mechanistic modelling of heat, water, energy and mass exchange between any kind of ectothermic organism and its environment. The NicheMapR ectotherm model is based on a Fortran program originally developed by Porter, Mitchell and Beckman for predicting core body temperature and evaporative water loss as a function of microclimatic conditions and behavioural thermoregulation. The model includes routines for computing steady state body temperature and evaporative water loss given two extreme microclimates (minimum and maximum shade) as computed by the NicheMapR microclimate model. Behavioural options include posture and colour change, shade‐seeking, panting, climbing and retreating underground. Here we configure the program to be called from R as part of the NicheMapR package and describe the model in detail including new functionality for modelling whole life‐cycle energy and water budgets using Dynamic Energy Budget theory. We include scripts for core operation of the ectotherm model as well as stand‐alone R scripts for running the DEB model. Example applications are provided in the paper and in the associated vignettes. The integrated microclimate and ectotherm models should provide a strong thermodynamic basis for determining the effects of environmental change on the behaviour, distribution and abundance of ectothermic organisms. [ABSTRACT FROM AUTHOR]

Microclimates are the thermal and hydric environments organisms actually experience, and estimates of them are increasingly needed in environmental research. The availability of global weather and terrain datasets, together with increasingly sophisticated microclimate modelling tools, makes the prospect of a global, web‐based microclimate estimation procedure feasible.We have developed such an approach for the r programming environment which integrates existing r packages for obtaining terrain and sub‐daily atmospheric forcing data (elevatr and rncep), and two complementary microclimate modelling packages (NicheMapR and microclima). The procedure can be used to generate NicheMapR's hourly time‐series outputs of above‐ and below‐ground conditions, including convective and radiative environments, soil temperature, soil moisture and snow cover, for a single point, using microclima to account for local topographic and vegetation effects. Alternatively, it can use microclima to produce high‐resolution grids of near‐surface temperatures, using NicheMapR to derive calibration coefficients normally obtained from experimental data.We validate this integrated approach against a series of microclimate observations used previously in the tests of the respective models and show equivalent performance.It is thus now feasible to produce realistic estimates of microclimate at fine (<30 m) spatial and temporal scales anywhere on earth, from 1957 to present. [ABSTRACT FROM AUTHOR]

Knowing where species occur is fundamental to many ecological and environmental applications. Species distribution models (SDMs) are typically based on correlations between species occurrence data and environmental predictors, with ecological processes captured only implicitly. However, there is a growing interest in approaches that explicitly model processes such as physiology, dispersal, demography and biotic interactions. These models are believed to offer more robust predictions, particularly when extrapolating to novel conditions. Many process–explicit approaches are now available, but it is not clear how we can best draw on this expanded modelling toolbox to address ecological problems and inform management decisions. Here, we review a range of process–explicit models to determine their strengths and limitations, as well as their current use. Focusing on four common applications of SDMs – regulatory planning, extinction risk, climate refugia and invasive species – we then explore which models best meet management needs. We identify barriers to more widespread and effective use of process‐explicit models and outline how these might be overcome. As well as technical and data challenges, there is a pressing need for more thorough evaluation of model predictions to guide investment in method development and ensure the promise of these new approaches is fully realised. [ABSTRACT FROM AUTHOR]

Insect life cycles are adapted to a seasonal climate by expressing alternative voltinism phenotypes—the number of generations in a year. Variation in voltinism phenotypes along latitudinal gradients may be generated by developmental traits at critical life stages, such as eggs. Both voltinism and egg development are thermally determined traits, yet independently derived models of voltinism and thermal adaptation refer to the evolution of dormancy and thermal sensitivity of development rate, respectively, as independent influences on life history. To reconcile these models and test their respective predictions, we characterized patterns of voltinism and thermal response of egg development rate along a latitudinal temperature gradient using the matchstick grasshopper genus Warramaba. We found remarkably strong variation in voltinism patterns, as well as corresponding egg dormancy patterns and thermal responses of egg development. Our results show that the switch in voltinism along the latitudinal gradient was explained by the combined predictions of the evolution of voltinism and of thermal adaptation. We suggest that latitudinal patterns in thermal responses and corresponding life histories need to consider the evolution of thermal response curves within the context of seasonal temperature cycles rather than based solely on optimality and trade-offs in performance. This article is part of the theme issue 'Physiological diversity, biodiversity patterns and global climate change: testing key hypotheses involving temperature and oxygen'. [ABSTRACT FROM AUTHOR]

Insights into the causal mechanisms that limit species distributions are likely to improve our ability to anticipate species range shifts in response to climate change. For species with complex life histories, a mechanistic understanding of how climate affects different lifecycle stages may be crucial for making accurate forecasts. Here, we use mechanistic niche modeling (NicheMapR) to derive "proximate" (mechanistic) variables for tadpole, juvenile, and adult Rana temporaria. We modeled the hydroperiod, and maximum and minimum temperatures of shallow (30 cm) ponds, as well as activity windows for juveniles and adults. We then used those ("proximate") variables in correlative ecological niche models (Maxent) to assess their role in limiting the species' current distribution, and to investigate the potential effects of climate change on R. temporaria across Europe. We further compared the results with a model based on commonly used macroclimatic ("distal") layers (i.e., bioclimatic layers from WorldClim). The maximum temperature of the warmest month (a macroclimatic variable) and maximum pond temperatures (a mechanistic variable) were the most important range‐limiting factors, and maximum temperature thresholds were consistent with the observed upper thermal limit of R. temporaria tadpoles. We found that range shift forecasts in central Europe are far more pessimistic when using distal macroclimatic variables, compared to projections based on proximate mechanistic variables. However, both approaches predicted extensive decreases in climatic suitability in southern Europe, which harbors a significant fraction of the species' genetic diversity. We show how mechanistic modeling provides ways to depict gridded layers that directly reflect the microenvironments experienced by organisms at continental scales, and to reconstruct those predictors without extrapolation under novel future conditions. Furthermore, incorporating those predictors in correlative ecological niche models can help shed light on range‐limiting processes, and can have substantial impacts on predictions of climate‐induced range shifts. [ABSTRACT FROM AUTHOR]

Many problems in pure and applied ecology require the quantification of above‐ and below‐ground microclimates. Here I describe a data set of hourly microclimates for the Australian continent, simulated from the years 1990 to 2017 across a grid of 1893 locations approx. 60 km apart. The data were generated with the NicheMapR microclimate model, driven by 0.05° gridded daily meteorological forcing data (air temperature, wind speed, humidity, cloud cover, rainfall), 0.025° elevation and 0.008° soil texture data. The above‐ground microclimate variables include horizontal plane solar radiation, solar zenith angle, sky temperature (from which down‐welling longwave radiation can be computed), air temperature, relative humidity and wind speed at 1 and 120 cm height, and snow depth. The below‐ground variables include soil temperature, pore humidity, soil moisture and soil water potential for 0, 2.5, 5, 10, 15, 20, 30, 50, 100 and 200 cm below‐ground. The computations are for four shade levels (0%, 50%, 70% and 90%). The data set can be used for a wide variety of applications, including the computation of heat and water budgets of organisms, the potential for vegetation growth, and the computation of stress and growth indices. The use of daily forcing data also allows assessments of the consequences of extreme events including heat waves. Example applications are provided for computing plant growth potential, grasshopper egg development, lizard body temperature and mammalian energy and water requirements. [ABSTRACT FROM AUTHOR]

It may be possible to avert threatened species declines by protecting refuges that promote species persistence during times of stress. To do this, we need to know where refuges are located, and when and which management actions are required to preserve, enhance or replicate them. Here we use a niche-based perspective to characterise refuges that are either fixed or shifting in location over ecological time scales (hours to centuries). We synthesise current knowledge of the role of fixed and shifting refuges, using threatened species examples where possible, and examine their relationships with stressors including drought, fire, introduced species, disease, and their interactions. Refuges often provide greater cover, water, food availability or protection from predators than other areas within the same landscapes. In many cases, landscape features provide refuge, but refuges can also arise through dynamic and shifting species interactions (e.g., mesopredator suppression). Elucidating the mechanisms by which species benefit from refuges can help guide the creation of new or artificial refuges. Importantly, we also need to recognise when refuges alone are insufficient to halt the decline of species, and where more intensive conservation intervention may be required. We argue that understanding the role of ecological refuges is an important part of strategies to stem further global biodiversity loss. [ABSTRACT FROM AUTHOR]

Colour variation across climatic gradients is a common ecogeographical pattern; yet there is long-standing contention over underlying causes, particularly selection for thermal benefits. We tested the evolutionary association between climate gradients and reflectance of near-infrared (NIR) wavelengths, which influence heat gain but are not visible to animals. We measured ultraviolet (UVA), visible (Vis) and NIR reflectance from calibrated images of 372 butterfly specimens from 60 populations (49 species, five families) spanning the Australian continent. Consistent with selection for thermal benefits, the association between climate and reflectance was stronger for NIR than UVA-Vis wavelengths. Furthermore, climate predicted reflectance of the thorax and basal wing, which are critical to thermoregulation; but it did not predict reflectance of the entire wing, which has a variable role in thermoregulation depending on basking behaviour. These results provide evidence that selection for thermal benefits has shaped the reflectance properties of butterflies. [ABSTRACT FROM AUTHOR]

Mechanistic forecasts of how species will respond to climate change are highly desired but difficult to achieve. Because processes at different scales are explicit in such models, careful assessments of their predictive abilities can provide valuable insights that will be relevant to functionally similar species. However, there are surprisingly few comprehensive field tests of mechanistic niche models in the literature. We applied a general, thermodynamically grounded modeling framework to determine the fundamental niche of an extremely well‐studied herbivorous ectotherm, the sleepy lizard Tiliqua rugosa. We then compared the model predictions with detailed long‐term field observations that included sub‐hourly data on microclimate, activity levels, home ranges, and body temperatures as well as annual to decadal patterns of body condition and growth. Body temperature predictions inferred from gridded climatic data were within 10% of empirically observed values and explained >70% of observed daytime activity patterns across all lizards. However, some periods of activity restriction were explained by predicted desiccation level rather than by temperature, and metabolically driven activity requirements were much lower than potential activity time. Decadal trajectories of field growth and body condition could also be explained to within 10% of observed values, with the variance in trajectories being attributable to whether individuals had access to permanent water. Continent‐wide applications of the model partly captured the inland distribution limit, but only after accounting for water limitations. Predicted changes in habitat suitability under six climate change scenarios were generally positive within the species' current range, but varied strongly with predicted rainfall. Temperature is regarded as the major factor that will restrict the distribution and abundance of lizards and other terrestrial ectotherms under climate change. Yet our findings show how water can be more important than temperature in constraining the activity, habitat requirements, and distribution limits of terrestrial ectotherms. Our results demonstrate the feasibility of first‐principles computation of the climatic limits on terrestrial animals from gridded environmental data, providing a coherent picture for how species will respond to climate change at different scales of space and time. [ABSTRACT FROM AUTHOR]

Biologists have focused their attention on the optical functions of light reflected at ultraviolet and human-visible wavelengths. However, most radiant energy in sunlight occurs in 'unseen' near-infrared (NIR) wavelengths. The capacity to reflect solar radiation at NIR wavelengths may enable animals to control heat gain and remain within their critical thermal limits. Here, using a continent-wide phylogenetic analysis of Australian birds, we show that species occupying hot, arid environments reflect more radiant energy in NIR wavelengths than species in thermally benign environments, even when controlling for variation in visible colour. Biophysical models confirm that smaller species gain a greater advantage from high NIR reflectivity in hot, arid environments, reducing water loss from compensatory evaporative cooling by up to 2% body mass per hour. These results highlight the importance of NIR reflectivity for thermal protection, which may become increasingly critical as the frequency of extreme climatic events increases. [ABSTRACT FROM AUTHOR]

Abstract: The phenological response is among the most important traits affecting a species’ sensitivity to climate. In insects, strongly seasonal environments often select for a univoltine life cycle such that one seasonal extreme is avoided as an inactive stage. Through understanding the underlying mechanisms for univoltinism, and the consequences of its failure, we can better predict insect responses to climate change. Here we combine empirical data and simulation studies to investigate the consequences of an unusual diapause mechanism in a parthenogenetic matchstick grasshopper, Warramaba virgo, from arid southern Australia. Our field body temperature measurements indicate that this species is a thermoconformer and our laboratory studies of the thermal response of feeding rate imply strong constraints on winter activity. However, the species exhibits no obligate winter diapause, and eggs can develop in 1 month under constant temperatures approximating the mean soil temperature at the time of oviposition (summer). We show that diurnal temperature cycles exceeding a peak of 36 °C inhibit egg development in summer, and that this is sufficient to prevent autumnal hatching of eggs. Development is also strongly retarded below 24 °C. Microclimate‐driven simulation studies of egg development show that these thermal responses provide robust maintenance of a univoltine life cycle, thereby resulting in survival of heat stress as an egg (due to limited developmental state) and avoidance of cold stress as a nymph and adult (due to overwintering in the soil as an egg). [ABSTRACT FROM AUTHOR]

Abstract: An understanding of the direct links between animals and their environment can offer insights into the drivers and constraints to animal movement. Constraints on movement interact in complex ways with the physiology of the animal (metabolism) and physical environment (food and weather), but can be modelled using physical principles of energy and mass exchange. Here, we describe a general, spatially explicit individual‐based movement model that couples a nutritional energy and mass budget model (dynamic energy budget theory) with a biophysical model of heat exchange. This provides a highly integrated method for constraining an ectothermic animal's movement in response to how food and microclimates vary in space and time. The model uses r to drive a NetLogo individual‐based model together with microclimate and energy‐ and mass‐budget modelling functions from the r package “ NicheMapR”. It explicitly incorporates physiological and morphological traits, behavioural thermoregulation, movement strategies and movement costs. From this, the model generates activity budgets of foraging and shade‐seeking, home range behaviour, spatial movement patterns and life history consequences under user‐defined configurations of food and microclimates. To illustrate the model, we run simulations of the Australian sleepy lizard Tiliqua rugosa under different movement strategies (optimising or satisficing) in two contrasting habitats of varying food and shade (sparse and dense). We then compare the results with real, fine‐scale movement data of a wild population throughout the breeding season. Our results show that (1) the extremes of movement behaviour observed in sleepy lizards are consistent with feeding requirements (passive movement) and thermal constraints (active movement), (2) the model realistically captures majority of the distribution of observed home range size, (3) both satisficing and optimising movement strategies appear to exist in the wild population, but home range size more closely approximates an optimising strategy, and (4) satisficing was more energetically efficient than optimising movement, which returned no additional benefit in metabolic fitness outputs. This framework for predicting physical constraints to individual movement can be extended to individual‐level interactions with the same or different species and provides new capabilities for forecasting future responses to novel resource and weather scenarios. [ABSTRACT FROM AUTHOR]

Abstract: Aim: Recognition that statistical models do not always reliably predict habitat suitability under future climate scenarios is leading increasingly to explicit incorporation of the physiological constraints that underlie species’ distributions into spatially explicit predictions. However, computational intensity constrains the use of high‐resolution, process‐explicit models. We examined whether geostatistical analysis can effectively interpolate a biophysical model, reducing the computational investment typically required for using mechanistic methods to inform physiological predictions. Location: New Zealand [40°40′00″ S 174°00′00″ E]. Methods: We used a spatially explicit, mechanistic microclimate model to predict hourly temperatures at five soil depths under two scenarios of climate warming. Using the predicted soil temperatures as input to a biophysical model of temperature‐dependent embryonic development, we estimated incubation temperatures and corresponding hatchling sex ratios for tuatara, a reptile with temperature‐dependent sex determination, at a submetre horizontal spatial resolution. We then applied ordinary kriging, a robust method of geostatistical interpolation, to estimate predictions throughout the full extent of our study location, an additional 480,000+ microsites, and validated the interpolation against an independent set of predictions. Results: Ordinary kriging accurately predicted spatial variability in incubation temperatures. Mean predictions were similar between methods, and error in the geospatial model generally decreased with increasing soil depth. Error was higher for the geospatial model of the ‘maximum warming’, compared with the ‘minimum warming’, scenario of climate change. Main conclusions: Our results show that ordinary kriging can be a reliable method for interpolating variability in high‐resolution predictions. However, the effects of error on the accuracy of interpolated predictions will become more severe as values approach a physiological threshold, such as the minimum and maximum incubation temperatures that result in extreme sex ratio bias. For distribution models, the widths of geographic areas predicted to be suitable for, in this case, maintaining balanced sex ratios, compared to those predicted to be unsuitable, may be narrower than in reality. [ABSTRACT FROM AUTHOR]

Context. Trapping of small vertebrates during their active hot summer periods is vital for conservation and impact assessment studies. Animal Ethics Committees (AECs) protect wildlife by enforcing arbitrary but restrictive temperature limits for trapping. Aims. Empirical data were gathered on the temperatures reached in different trap configurations to inform pragmatic ethical guidelines. Methods. Temperature was measured inside small vertebrate traps at two Australian arid zone sites to generate data on the thermal consequences of: (1) trap design and external shading; (2) provision of protective refuge substrates; and (3) timing of trap clearing. Key results. Shading and increased trap depth significantly reduced temperatures within pitfall traps. A conservative stressful upper temperature limit of 36°C was never exceeded inside deep, shaded, narrow pitfall traps at one study site and only between 1100 and 1300 hours on 3 days at the hotter site, despite ambient temperatures reaching over 42°C. By contrast, potentially lethal upper temperatures were reached in wider, shallower bucket pit traps on most days at both sites, even when optimal shading and refuge substrates were employed. Deployment of surface traps under vegetation and with additional shading significantly reduced maximum temperatures experienced. Temperatures inside shaded Elliott and funnel traps generally tracked ambient air temperatures and thus typically exceeded conservative threshold temperatures between 0700 and 1900 hours when ambient temperatures exceeded 36°C. Conclusions. Temperatures experienced in optimal deep, shaded traps when ambient temperatures exceeded 40°C were 31°C lower than surface temperatures and similar to temperatures recorded at 20 cm below the soil surface, where many species would typically take refuge at these times. Implications. Data suggest that deep (60 cm), narrow pitfall traps with elevated lids for shade and shelter substrate inside should enable trapping to be conducted safely in the study region during summer (December to February). This is even the case in extremely hot weather, as long as trapped animals are removed within 4 h of sunrise. Ecophysiological studies of thermal tolerance within optimum trap arrangements revealed by the present study will allow field ecologists and AECs to develop informed site-specific trapping protocols. [ABSTRACT FROM AUTHOR]

Microclimatic variables are necessary for a wide range of pure and applied problems in environmental science. In ecology, microclimatic conditions are prerequisites for modelling the heat and water budgets of organisms, from which climatic constraints on behaviour, life histories, distribution and abundance can be inferred. Despite the critical importance of microclimates, there is no general-purpose, accessible microclimate model available for use in ecological studies. Here we introduce and document the microclimate model of the biophysical modelling package NicheMapR, an R package that includes a suite of programs for mechanistic modelling of heat and mass exchange between organisms and their environments. The NicheMapR microclimate model is based on a Fortran program originally developed by Porter, Mitchell, Beckman and McCullough for predicting hourly above- and below-ground conditions from meteorological, terrain, vegetation and soil data. The model includes routines for computing solar radiation, including effects of shading, slope, aspect and horizon angles (hillshade), and can include variable substrate properties with depth. Here we configure the program to be called from R as part of the NicheMapR package, and describe the model in detail including new functionality for modelling soil water balance and snow, optional input of hourly or daily weather input data, and an R implementation of the Global Aerosol Data Set for obtaining local estimates of aerosol profiles as input to the model. We include scripts for core operation of the model, for building a global, monthly long-term average dataset with all necessary environmental inputs, for computing physical properties of air, and for running the model with the global climate database. Example applications are provided in the paper and in the associated vignettes, including customisation the model to run with user-supplied weather inputs. [ABSTRACT FROM AUTHOR]

Body size scaling relationships allow biologists to study ecological phenomena in terms of individual level metabolic processes. Recently, dynamic energy budget (DEB) theory has been shown to offer novel insights on the effect of body size on biological rates., We test whether DEB theory and its unique partitioning of biomass into reserve and structural components can explain the effect of egg size on hatch time and the time course of respiration in insect embryos., We find that without any parameterization (calibration), DEB theory is able to predict hatch time for eggs sizes spanning four orders of magnitude from fundamental biological processes., We find, however, that the standard DEB model poorly predicts the time course of respiration, particularly in early embryonic development where a strong effect of egg size is observed. Further, we show that other theoretical models also poorly predict early embryonic respiration., By modifying the assumption that a fresh egg is entirely reserve, we show that embryonic respiration and hatch time can be better predicted by the DEB model., Useful theories in metabolic ecology, such as DEB theory, can help explain universal scaling patterns in development times. However, simple theoretical models must be expanded if they are to capture the scaling of metabolic rate in insect eggs., A is available for this article. [ABSTRACT FROM AUTHOR]