Hypoxia tolerance and its variation with temperature, activity, and body mass, are critical ecophysiological traits through which climate impacts marine ectotherms. To date, experimental determination of these traits is limited to a small subset of modern species. We leverage the close coupling of carbon and oxygen in animal metabolism to mechanistically relate these traits to the carbon isotopes in fish otoliths (δC).
View Article and Find Full Text PDFGlob Chang Biol
October 2024
Tropical reef ecosystems are strongly influenced by the composition of coral species, but the factors influencing coral diversity and distributions are not fully understood. Here we demonstrate that large variations in the relative abundance of three major coral species across adjacent Caribbean reef sites are strongly related to their different low O tolerances. In laboratory experiments designed to mimic reef conditions, the cumulative effect of repeated nightly low O drove coral bleaching and mortality, with limited modulation by temperature.
View Article and Find Full Text PDFThe ability to anticipate marine habitat shifts responding to climate variability has high scientific and socioeconomic value. Here we quantify interannual-to-decadal predictability of habitat shifts by combining trait-based aerobic habitat constraints with a suite of initialized retrospective Earth System Model forecasts, for diverse marine ecotypes in the North American Large Marine Ecosystems. We find that aerobic habitat viability, defined by joint constraints of temperature and oxygen on organismal energy balance, is potentially predictable in the upper-600 m ocean, showing a substantial improvement over a simple persistence forecast.
View Article and Find Full Text PDFThe minimum O2 needed to fuel the demand of aquatic animals is commonly observed to increase with temperature, driven by accelerating metabolism. However, recent measurements of critical O2 thresholds ("Pcrit") reveal more complex patterns, including those with a minimum at an intermediate thermal "optimum". To discern the prevalence, physiological drivers, and biogeographic manifestations of such curves, we analyze new experimental and biogeographic data using a general dynamic model of aquatic water breathers.
View Article and Find Full Text PDFIn an ocean that is rapidly warming and losing oxygen, accurate forecasting of species' responses must consider how this environmental change affects fundamental aspects of their physiology. Here, we develop an absolute metabolic index (Φ) that quantifies how ocean temperature, dissolved oxygen and organismal mass interact to constrain the total oxygen budget an organism can use to fuel sustainable levels of aerobic metabolism. We calibrate species-specific parameters of Φ with physiological measurements for red abalone (Haliotis rufescens) and purple urchin (Strongylocentrotus purpuratus).
View Article and Find Full Text PDFProc Natl Acad Sci U S A
October 2022
Carbonate mud represents one of the most important geochemical archives for reconstructing ancient climatic, environmental, and evolutionary change from the rock record. Mud also represents a major sink in the global carbon cycle. Yet, there remains no consensus about how and where carbonate mud is formed.
View Article and Find Full Text PDFFossil records from tropical oceans predict biodiversity loss in a warmer world.
View Article and Find Full Text PDFInsect pests substantially reduce yields of three staple grains-rice, maize, and wheat-but models assessing the agricultural impacts of global warming rarely consider crop losses to insects. We use established relationships between temperature and the population growth and metabolic rates of insects to estimate how and where climate warming will augment losses of rice, maize, and wheat to insects. Global yield losses of these grains are projected to increase by 10 to 25% per degree of global mean surface warming.
View Article and Find Full Text PDFOxygen concentrations are hypothesized to decrease in many areas of the ocean as a result of anthropogenically driven climate change, resulting in habitat compression for pelagic animals. The oxygen partial pressure, pO , at which blood is 50% saturated (P ) is a measure of blood oxygen affinity and a gauge of the tolerance of animals for low ambient oxygen. Tuna species display a wide range of blood oxygen affinities (i.
View Article and Find Full Text PDFDifficulty in characterizing the relationship between climatic variability and climate change vulnerability arises when we consider the multiple scales at which this variation occurs, be it temporal (from minute to annual) or spatial (from centimetres to kilometres). We studied populations of a single widely distributed butterfly species, Chlosyne lacinia, to examine the physiological, morphological, thermoregulatory and biophysical underpinnings of adaptation to tropical and temperate climates. Microclimatic and morphological data along with a biophysical model documented the importance of solar radiation in predicting butterfly body temperature.
View Article and Find Full Text PDFWhether movement will enable organisms to alleviate thermal stress is central to the biodiversity implications of climate change. We use the temperature-dependence of ectotherm performance to investigate the fitness consequences of movement. Movement to an optimal location within a 50 km radius will only offset the fitness impacts of climate change by 2100 in 5 per cent of locations globally.
View Article and Find Full Text PDFEvolutionary history and physiology mediate species responses to climate change. Tropical species that do not naturally experience high temperature variability have a narrow thermal tolerance compared to similar taxa at temperate latitudes and could therefore be most vulnerable to warming. However, the thermal adaptation of a species may also be influenced by spatial temperature variations over its geographical range.
View Article and Find Full Text PDFBiological impacts of climate warming are predicted to increase with latitude, paralleling increases in warming. However, the magnitude of impacts depends not only on the degree of warming but also on the number of species at risk, their physiological sensitivity to warming and their options for behavioural and physiological compensation. Lizards are useful for evaluating risks of warming because their thermal biology is well studied.
View Article and Find Full Text PDFProc Natl Acad Sci U S A
May 2008
The impact of anthropogenic climate change on terrestrial organisms is often predicted to increase with latitude, in parallel with the rate of warming. Yet the biological impact of rising temperatures also depends on the physiological sensitivity of organisms to temperature change. We integrate empirical fitness curves describing the thermal tolerance of terrestrial insects from around the world with the projected geographic distribution of climate change for the next century to estimate the direct impact of warming on insect fitness across latitude.
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