A5026527616- Physiological and biochemical adaptations
- Avian ecology and behavior
- Animal Behavior and Reproduction
- Bat Biology and Ecology Studies
- Species Distribution and Climate Change
- Wildlife Ecology and Conservation
- Effects of Environmental Stressors on Livestock
- Ecology and Vegetation Dynamics Studies
- Fish Ecology and Management Studies
- Animal Ecology and Behavior Studies
- Climate Change and Health Impacts
- Isotope Analysis in Ecology
- Climate variability and models
- Genetic diversity and population structure
- Plant and animal studies
- Primate Behavior and Ecology
- Marine animal studies overview
- Evolution and Paleontology Studies
- Insect and Arachnid Ecology and Behavior
- Amphibian and Reptile Biology
- Animal Behavior and Welfare Studies
- Animal Nutrition and Physiology
- Bird parasitology and diseases
- Thermoregulation and physiological responses
- Fish Biology and Ecology Studies
University of Pretoria
2016-2025
South African National Biodiversity Institute
2018-2025
Hebei University
2022
University of Florida
2022
Syracuse University
2022
University of Exeter
2022
University of Tasmania
2022
Vrije Universiteit Amsterdam
2022
Pacific Northwest National Laboratory
2022
Instituto Pirenaico de Ecología
2022
Severe heat waves have occasionally led to catastrophic avian mortality in hot desert environments. Climate change models predict increases the intensity, frequency and duration of waves. A model evaporative water requirements survival times during hottest part day reveals that predicted maximum air temperatures will result large fractional (in small birds, equivalent 150–200 % current values), which severely reduce extremely weather. By 2080s, birds experience reduced much more frequently...
Significance Using measured rates of evaporative water loss, hourly gridded weather data, a 4 °C warming scenario, and physiological models, we show that songbirds in the deserts southwestern United States are increasingly susceptible to death from dehydration on hot days. Smaller birds lose at proportionally higher rate, hence more vulnerable than larger lethal arising greater cooling demands. Our analysis indicates that, by end present century, exposure potentially conditions could least...
Significance We synthesized physiological and behavioral data to evaluate the risks of acute, lethal effects extreme heat events versus sublethal costs chronic exposure sustained hot weather for birds inhabiting southern Africa’s Kalahari Desert over course 21st century. The risk mass mortality similar those predicted American southwest sometimes observed in Australia will remain low birds. However, exposure, manifested as progressive loss body condition, delayed fledging, reduced fledging...
Conventionally, the size, shape, and biomechanics of cartilages are determined by their voluminous extracellular matrix. By contrast, we found that multiple murine consist lipid-filled cells called lipochondrocytes. Despite resembling adipocytes, lipochondrocytes were molecularly distinct produced lipids exclusively through de novo lipogenesis. Consequently, grew uniform lipid droplets resisted systemic surges did not enlarge upon obesity. Lipochondrocytes also lacked mobilization factors,...
Many birds exhibit short-term, reversible adjustments in basal metabolic rate (BMR), but the overall contribution of phenotypic plasticity to avian diversity remains unclear. The available BMR data include estimates from living natural environments and captive-raised more homogenous, artificial environments. All previous analyses interspecific variation have pooled these data. We hypothesized that is an important contributor BMR, populations general differences compared wild-caught...
ABSTRACT Many birds can defend body temperature (Tb) far below air (Ta) during acute heat exposure, but relatively little is known about how avian tolerance and evaporative cooling capacity varies with mass (Mb), phylogeny or ecological factors. We determined maximum rates of dissipation thermal end points (Tb Ta associated thermoregulatory failure) in three southern African ploceid passerines, the scaly-feathered weaver (Sporopipes squamifrons, Mb≈10 g), sociable (Philetairus socius, Mb≈25...
Summary Artificial night lighting threatens to disrupt strongly conserved light‐dependent processes in animals and may have cascading effects on ecosystems as species interactions become altered. Insectivorous bats their prey been involved a nocturnal, co‐evolutionary arms race for millions of years. Lights interfere with anti‐bat defensive behaviours moths, complex globally ubiquitous interaction between insects, ultimately leading detrimental consequences global scale. We combined...
Click to increase image sizeClick decrease size This article is part of the following collections: Emu's First 120 Years: Landmark Papers Change in Austral Ornithology
Environmental temperatures that exceed body temperature (Tb) force endothermic animals to rely solely on evaporative cooling dissipate heat. However, heat dissipation can be drastically reduced by environmental humidity, imposing a thermoregulatory challenge. The goal of this study was investigate the effects humidity thermoregulation desert birds and compare sensitivity cutaneous respiratory evaporation vapor density gradients. Rates water loss, metabolic rate, Tb were measured in exposed...
Abstract Aim The ability of endotherms to physiologically regulate body temperature ( T b ) is presumed be important in the adaptive radiation birds and mammals. Recently, attention has shifted towards determining extent energetic significance variation documented an ever‐expanding list species. Thus, we provide first global synthesis ecological evolutionary correlates mammalian . Location World‐wide Methods We conducted a phylogenetically informed analysis using two complementary metrics,...
Intense heat waves are occurring more frequently, with concomitant increases in the risk of catastrophic avian mortality events via lethal dehydration or hyperthermia. We quantified risks hyperthermia and for 10 Australian arid-zone avifauna species during 21st century, by synthesizing thermal physiology data on evaporative water losses tolerance limits. evaluated exceedance limits absence drinking hottest part day under recent climatic conditions, compared to those predicted end this...
Abstract The world’s warm deserts are predicted to experience disproportionately large temperature increases due climate change, yet the impacts on global desert biodiversity remain poorly understood. Because species in live close their physiological limits, additional warming may induce local extinctions. Here, we combine change projections with biophysical models and distributions predict of birds globally. Our results show heterogeneous between within deserts. Moreover, spatial patterns...
Abstract The role of atmospheric humidity in the evolution endotherms' thermoregulatory performance remains largely unexplored, despite fact that elevated is known to impede evaporative cooling capacity. Using a phylogenetically informed comparative framework, we tested hypothesis pronounced hyperthermia tolerance among birds occupying humid lowlands evolved reduce impact humidity‐impeded scope for heat dissipation by comparing limits (HTLs; maximum tolerable air temperature), body...
Abstract The rates at which birds use energy may have profound effects on fitness, thereby influencing physiology, behavior, ecology and evolution. Comparisons of standardized metabolic (e.g., lower upper limits power output) present a method for elucidating the ecological evolutionary factors interface between physiology life history in birds. In this paper we review variation avian [basal rate (BMR; minimum normothermic rate), summit (Msum; maximal thermoregulatory (MMR; exercise rate)],...
Basal metabolic rate (BMR) represents the minimum maintenance energy requirement of an endotherm and has far-reaching consequences for interactions between animals their environments. Avian BMR exhibits considerable variation that is independent body mass. Some long-distance migrants have been found to exhibit particularly high BMR, traditionally interpreted as being related energetic demands migration. Here we use a global dataset evaluate differences in non-migrants, examine effects...