Responses of reptiles to fluctuating thermal environments: behaviour or biochemistry? I propose a conceptual shift in the way thermal physiology of reptiles is interpreted, questioning the predominant role of behaviour in reptilian thermoregulation. I will test the hypothesis that changes in cellular biochemistry are an important mechanism by which reptiles respond to environmental fluctuations. I will determine the relationship between metabolic enzyme activity and performance functions, and ....Responses of reptiles to fluctuating thermal environments: behaviour or biochemistry? I propose a conceptual shift in the way thermal physiology of reptiles is interpreted, questioning the predominant role of behaviour in reptilian thermoregulation. I will test the hypothesis that changes in cellular biochemistry are an important mechanism by which reptiles respond to environmental fluctuations. I will determine the relationship between metabolic enzyme activity and performance functions, and the results may call for a re-assessment of current concepts such as the notion that reptiles must achieve "preferred" body temperatures to maintain performance.Read moreRead less
Of birds and bees: membrane lipids and the determination of maximum lifespan. The underlying mechanisms that determine why different animals have different maximum lifespans are unknown. Why do queen bees live for years but the genetically-identical workers bees live for only weeks? Similarly, to understand why birds live much longer than similar-sized mammals will give immense insight into the processes that cause ageing. Understanding the aging process in animals will have significant implicat ....Of birds and bees: membrane lipids and the determination of maximum lifespan. The underlying mechanisms that determine why different animals have different maximum lifespans are unknown. Why do queen bees live for years but the genetically-identical workers bees live for only weeks? Similarly, to understand why birds live much longer than similar-sized mammals will give immense insight into the processes that cause ageing. Understanding the aging process in animals will have significant implications for human health as the biggest risk factor for most diseases is age. Such understanding will help to cope with the worldwide problems of an aging population.Read moreRead less
Design of the cardiovascular system of living and fossil vertebrates. This project aims to understand how the heart and blood vessels evolved in mammals, birds, reptiles and fish to achieve efficiency. The heart is the most important organ for life. The project will study the structure and function of vertebrate animals’ hollow and spongy hearts to show how energetics shaped their evolution. It will measure arterial holes in bone to gauge brain and bone metabolism, which opens up a new way to me ....Design of the cardiovascular system of living and fossil vertebrates. This project aims to understand how the heart and blood vessels evolved in mammals, birds, reptiles and fish to achieve efficiency. The heart is the most important organ for life. The project will study the structure and function of vertebrate animals’ hollow and spongy hearts to show how energetics shaped their evolution. It will measure arterial holes in bone to gauge brain and bone metabolism, which opens up a new way to measure metabolism in extinct animals directly from fossils, rather than by inference from living relatives. The expected outcome is to correlate cardiovascular design and metabolic rates of organs.Read moreRead less
Plasticity in placental vasculature and the evolution of viviparity in lizards. This cross-disciplinary research will provide thorough understanding of the reproductive physiology of animals with different forms of reproduction, information critical for conservation and management of Australia's biodiversity. Australia's unique reptiles provide the best animal system in the world for research in this area. Our research on maternal-embryonic interactions in this animal model has direct implicatio ....Plasticity in placental vasculature and the evolution of viviparity in lizards. This cross-disciplinary research will provide thorough understanding of the reproductive physiology of animals with different forms of reproduction, information critical for conservation and management of Australia's biodiversity. Australia's unique reptiles provide the best animal system in the world for research in this area. Our research on maternal-embryonic interactions in this animal model has direct implications for understanding some medical disorders, such as human angiogenic disorders. The research will strengthen ties internationally through research in South Africa, and provide training in combined biological and medical technologies. It will maintain Australia's long-term leadership in this area of research.Read moreRead less
The physiological mechanisms underlying animal group dynamics. The project aims to provide novel insights into how individual differences in muscle biomechanics and metabolism constrain group assemblages, and the extent to which these constraints can cause fission and fusion of populations in changing environments. This research is significant because most ecological and evolutionary processes and their management occur at the level of groups. The project expects to yield a theoretical model cal ....The physiological mechanisms underlying animal group dynamics. The project aims to provide novel insights into how individual differences in muscle biomechanics and metabolism constrain group assemblages, and the extent to which these constraints can cause fission and fusion of populations in changing environments. This research is significant because most ecological and evolutionary processes and their management occur at the level of groups. The project expects to yield a theoretical model calibrated against empirical data to predict group dynamics of natural populations in changing environments, and of human crowds as diseases and lifestyle change physiological capacities.Read moreRead less
Evolution of viviparity in reptiles: the fundamental role of junctional complexes. This project utilises unique Australian reptile fauna to understand global questions in fundamental biology. We will discover basic biological information on native species, which will be important in future conservation of Australian ecosystems and animals and ultimately in helping to maintain Australia's biodiversity. The project also provides training opportunities for graduate and undergraduate students in ....Evolution of viviparity in reptiles: the fundamental role of junctional complexes. This project utilises unique Australian reptile fauna to understand global questions in fundamental biology. We will discover basic biological information on native species, which will be important in future conservation of Australian ecosystems and animals and ultimately in helping to maintain Australia's biodiversity. The project also provides training opportunities for graduate and undergraduate students in several different research methods that are widely applicable in the more general Australian workforce. Because the research work is genuinely cross-disciplinary research, its findings are applicable to both biological and medically oriented technologies.Read moreRead less
Evaluating the effects of fipronil, a moderately persistent new generation pesticide, on Australian native vertebrates. The Australian Plague Locust Commission is considering replacing an organophosphate pesticide with fipronil, a relatively new phenyl pyrazole pesticide, because it more specifically targets invertebrate animals. However, fipronil is more environmentally persistent, has high lipid solubility, is known to disrupt thyroid function and has wide variation in its toxicity to vertebra ....Evaluating the effects of fipronil, a moderately persistent new generation pesticide, on Australian native vertebrates. The Australian Plague Locust Commission is considering replacing an organophosphate pesticide with fipronil, a relatively new phenyl pyrazole pesticide, because it more specifically targets invertebrate animals. However, fipronil is more environmentally persistent, has high lipid solubility, is known to disrupt thyroid function and has wide variation in its toxicity to vertebrates . These characteristics place native vertebrate species at risk. Further, because peak locust activity is coincident with vertebrate breeding, there is likelihood that fipronil will affect development of young and the health of adults. We propose to launch the first comprehensive study of fipronil's effects on the health and vitality of native vertebrate adults and their offspring. We will focus on dasyurid marsupials and native birds that co-occur with plague locusts.Read moreRead less
Genetic mechanisms of metabolic control and thermal sensing during thermoregulation. This research will significantly advance understanding of how animals can respond to climate change, and the results will benefit wildlife management processes. The proposed research will lead to collaboration with Prof. Ken Storey an ISI highly cited author and expert in microarray analysis. The cDNA microarray for Crocodylus porosus which I will construct in the proposed research will be a valuable resource ....Genetic mechanisms of metabolic control and thermal sensing during thermoregulation. This research will significantly advance understanding of how animals can respond to climate change, and the results will benefit wildlife management processes. The proposed research will lead to collaboration with Prof. Ken Storey an ISI highly cited author and expert in microarray analysis. The cDNA microarray for Crocodylus porosus which I will construct in the proposed research will be a valuable resource for Australia by increasing collaborations, and it will help find the cause of problems prevalent in the crocodile industry such as runt animals that significantly decrease production efficiency.Read moreRead less
Investigating the "membrane pacemaker" theory of aging. All animals age and die but the basis of the aging process is still not completely understood. Recent Australian research into the basis of the metabolism in different animals has suggested that the fatty acid composition of biological membranes may be the final part of the puzzle. Understanding why different species have such different lifespans will give profound insight into the aging process. Because it is such a fundamental biological ....Investigating the "membrane pacemaker" theory of aging. All animals age and die but the basis of the aging process is still not completely understood. Recent Australian research into the basis of the metabolism in different animals has suggested that the fatty acid composition of biological membranes may be the final part of the puzzle. Understanding why different species have such different lifespans will give profound insight into the aging process. Because it is such a fundamental biological process, understanding how aging occurs and what determines lifespan will have obvious benefits to understanding the basis of many aging-associated diseases. Understanding the role of dietary fats in influencing lifespan will also be of benefit to the community, both national and international. Read moreRead less
Does testosterone produce duds or studs? A performance-based examination of the Immunocompetence Handicap Hypothesis. The evolutionary persistence of testosterone (T) as a vertebrate reproductive hormone is viewed as a double-edged sword. On the one hand T secretion is required for development and expression of appropriate reproductive functions. On the other hand T is known to suppress immune functions and is thus considered a liability to male health. We are examining an alternate hypothesis: ....Does testosterone produce duds or studs? A performance-based examination of the Immunocompetence Handicap Hypothesis. The evolutionary persistence of testosterone (T) as a vertebrate reproductive hormone is viewed as a double-edged sword. On the one hand T secretion is required for development and expression of appropriate reproductive functions. On the other hand T is known to suppress immune functions and is thus considered a liability to male health. We are examining an alternate hypothesis: that T-induced immunosuppression benefits breeding males by protecting their physical performance levels during immune challenge. We will examine this hypothesis by quantifying the interactive effects of T and immune challenge on the aerobic capacity of male birds.Read moreRead less