More than defence: primary roles for cyanogenic glucosides. The tropical crop, sorghum, produces toxic cyanide to avoid being eaten by herbivores, but this diverts resources away from growth and reproduction. Using non-toxic sorghum mutants, this project seeks to explain how cyanide production is regulated and enhance agricultural efficiency in the face of climate change.
Testing metabolic theories in ecology. There are striking similarities in the way plants and animals take up and use energy (metabolism), despite enormous variation in size and life-style. This project will make the first experimental comparison of the predictions of the two major theories for these broad patterns. The results will significantly progress this controversial and exciting field.
Are evolutionary refugia traps for endemic species? This project aims to determine whether species that have small geographic ranges and which live in historically stable refugia have evolved narrow climatic tolerances. The project will compare such species with more widespread, related species living in the same areas and combine field- and lab-based estimates of physiological tolerances with genomic estimates of population history and diversity. The expected outcome is to test the prediction f ....Are evolutionary refugia traps for endemic species? This project aims to determine whether species that have small geographic ranges and which live in historically stable refugia have evolved narrow climatic tolerances. The project will compare such species with more widespread, related species living in the same areas and combine field- and lab-based estimates of physiological tolerances with genomic estimates of population history and diversity. The expected outcome is to test the prediction from evolutionary theory that small-range, refugial species are intrinsically more sensitive to climatic change. The project expects to provide improved guidance for ecological management of biodiversity hotspots.Read moreRead less
Does mother know best? Unifying proximate causation and ultimate explanation in mammalian sex allocation. The study of parental effects is a fundamental area in evolutionary ecology, but is characterised by poor integration of theory (ultimate causation) and physiology (proximate causation). This is true in sex allocation research that focuses almost exclusively on ultimate causation without integrating the physiological mechanisms for sex ratio adjustment. Using a combination of experiments and ....Does mother know best? Unifying proximate causation and ultimate explanation in mammalian sex allocation. The study of parental effects is a fundamental area in evolutionary ecology, but is characterised by poor integration of theory (ultimate causation) and physiology (proximate causation). This is true in sex allocation research that focuses almost exclusively on ultimate causation without integrating the physiological mechanisms for sex ratio adjustment. Using a combination of experiments and modelling, the project addresses this gap in understanding mammalian sex allocation, specifically: the lack of known mechanism; the connection between proximate mechanistic explanation and adaptive fitness explanations; and, knowledge on constraints. This project argues that one mechanism, pre-implantation glucose levels, links adaptive hypotheses with proximate causation. Read moreRead less
Brown is the new green: grassland responses to drought and heat. This project aims to improve accuracy and precision in predicting the impact of water availability and heat stress on grassland function. Grassland ecosystems are important reservoirs of global biodiversity and carbon storage. Grasslands are highly sensitive to drought and heat stress, but studies recently showed that current grassland models cannot predict these responses because they do not adequately represent the key processes ....Brown is the new green: grassland responses to drought and heat. This project aims to improve accuracy and precision in predicting the impact of water availability and heat stress on grassland function. Grassland ecosystems are important reservoirs of global biodiversity and carbon storage. Grasslands are highly sensitive to drought and heat stress, but studies recently showed that current grassland models cannot predict these responses because they do not adequately represent the key processes of physiological drought tolerance, leaf browning, and species traits. This project will collect targeted data sets in order to develop and test model representations of these key processes. This will provide significant benefits, such as greatly increasing capacity to predict the impact of drought and heat stress on grasslands, at scales ranging from field to globe.Read moreRead less
Hydraulic control on water use, growth and survival in tropical rainforest. This project aims to measure drought-related limits to water transport in the woody xylem tissue of trees in Australian tropical rainforests, to understand how this influences tree water use, photosynthesis, health and mortality risk. Tropical rainforests are sensitive to climate variability, especially drought, but this sensitivity is poorly understood, despite large effects regionally and globally. This project will co ....Hydraulic control on water use, growth and survival in tropical rainforest. This project aims to measure drought-related limits to water transport in the woody xylem tissue of trees in Australian tropical rainforests, to understand how this influences tree water use, photosynthesis, health and mortality risk. Tropical rainforests are sensitive to climate variability, especially drought, but this sensitivity is poorly understood, despite large effects regionally and globally. This project will compare forests that contrast strongly in seasonal drought stress, and use the information to develop a model designed for species-diverse forest, with subsequent potential global application. The understanding gained will enable widely applicable advances designed to feed through rapidly to regional- and global-scale models that inform land use, economic and social policy-making.Read moreRead less
Top-down rehydration: role of multiple water sources in mangrove function. This project aims to combine cutting-edge analytical and imaging techniques to assess contributions of atmospheric water sources to shoot-water balances, identify leaf traits associated with top-down rehydration, and determine the relative importance of different sources of water used by mangroves in maintenance of photosynthetic carbon assimilation along natural gradients in salinity and aridity. The capacity of shoots ....Top-down rehydration: role of multiple water sources in mangrove function. This project aims to combine cutting-edge analytical and imaging techniques to assess contributions of atmospheric water sources to shoot-water balances, identify leaf traits associated with top-down rehydration, and determine the relative importance of different sources of water used by mangroves in maintenance of photosynthetic carbon assimilation along natural gradients in salinity and aridity. The capacity of shoots to absorb atmospheric water could profoundly affect the diversity, survival and productivity of mangroves where high soil salinity limits water uptake by roots, particularly during hot, dry conditions.Read moreRead less
Temperature sensitivity of soil respiration and its components. This project aims to demonstrate how temperate evergreen forests could buffer against climate change. Soil respiration returns around half the carbon taken up by forests to the atmosphere. This project will characterise and quantify how microbes and roots in soils depend on temperature and substrate supply, and so predict how rising temperatures and drought will affect forests as natural carbon sequestration sinks. This project will ....Temperature sensitivity of soil respiration and its components. This project aims to demonstrate how temperate evergreen forests could buffer against climate change. Soil respiration returns around half the carbon taken up by forests to the atmosphere. This project will characterise and quantify how microbes and roots in soils depend on temperature and substrate supply, and so predict how rising temperatures and drought will affect forests as natural carbon sequestration sinks. This project will resolve the roles of environmental drivers of soil respiration across forests; integrate mechanistic understanding of differing plant and microbial responses to temperature within a common modelling framework; and evaluate the implications of this knowledge in predictions of climatic impacts on terrestrial carbon cycling.Read moreRead less
Woodland response to elevated CO2 in free air carbon dioxide enrichment: does phosphorus limit the sink for Carbon? This project will determine if growth of Australian woodland trees is limited by phosphorus, and if that limitation means the woodland carbon sink is constrained from responding to rising atmospheric CO2. Assessing the CO2 sink capacity of native eucalypt woodland is central to meeting Australia's domestic and international carbon accounting commitments.
Silicon defences for plant protection. This project aims to study how silicon uptake in grasses affects plant susceptibility aboveground. Grasses contain more silicon than nearly any other plant, which they acquire entirely from the soil. Silicon increases plant resistance to herbivores, disease and drought, but up to 25 per cent of grass productivity is lost to root herbivores, a situation compounded by water stress. Silicon uptake is poorly understood, but root herbivory and changing rainfall ....Silicon defences for plant protection. This project aims to study how silicon uptake in grasses affects plant susceptibility aboveground. Grasses contain more silicon than nearly any other plant, which they acquire entirely from the soil. Silicon increases plant resistance to herbivores, disease and drought, but up to 25 per cent of grass productivity is lost to root herbivores, a situation compounded by water stress. Silicon uptake is poorly understood, but root herbivory and changing rainfall patterns can either impair uptake or induce the plant to take up more silicon. The goal of this project is to optimise silicon-based resistance in grasses and exploit this for plant protection from invasive pests and drought.Read moreRead less