Boom and bust: the role of fire and rain in driving the dynamics of seeds and rodents in arid Australia. The arid Australian environment oscillates between spectacular boom periods, when biotic productivity and diversity are high, and busts, when biotic resources are depleted. This project first outlines a conceptual model of this dynamic and complex system. It then investigates the roles of rainfall and fire in driving boom-bust events, focusing particularly on food resources (seeds) and their ....Boom and bust: the role of fire and rain in driving the dynamics of seeds and rodents in arid Australia. The arid Australian environment oscillates between spectacular boom periods, when biotic productivity and diversity are high, and busts, when biotic resources are depleted. This project first outlines a conceptual model of this dynamic and complex system. It then investigates the roles of rainfall and fire in driving boom-bust events, focusing particularly on food resources (seeds) and their consumers (desert rodents) in the hyper-variable Simpson Desert. We propose observations and experiments to quantify how these climatic events affect seed production, seed fate, and ultimately the dynamics of desert rodents, and outline their importance for effective management of the desert environment.Read moreRead less
Influence of energy intake on reproduction. Understanding reproduction is fundamentally important to ecology and conservation. Despite intensive research, the processes that regulate energy acquisition and allocation for reproduction are still unclear for most animal species. Many of the obstacles to progress in this field of research are logistical, reflecting the complexity and temporal overlap of significant components of energy allocation pathways. Our proposed study avoids many of these l ....Influence of energy intake on reproduction. Understanding reproduction is fundamentally important to ecology and conservation. Despite intensive research, the processes that regulate energy acquisition and allocation for reproduction are still unclear for most animal species. Many of the obstacles to progress in this field of research are logistical, reflecting the complexity and temporal overlap of significant components of energy allocation pathways. Our proposed study avoids many of these logistical difficulties by focusing on animals (snakes) that display clear temporal partitioning between successive segments of the reproductive cascade (i.e., vitellogenesis, ovulation, embryogenesis); and by adopting a simple but novel method (based on stable isotope analysis) to tease apart the relationship between energy acquisition and energy expenditure in different phases of the animal's life-history.Read moreRead less
Facultative sex-determination in a montane lizard. Why is the sex of some reptiles determined by their genetic constitution (sometimes involving heteromorphic sex chromosomes) whereas in other species the animal's sex is determined by the environment (especially, incubation temperature)? Multiple phylogenetic transitions between genetic sex determination (GSD) and environmental sex determination (ESD) suggest that these alternative modes of sex determination possess adaptive significance. Howe ....Facultative sex-determination in a montane lizard. Why is the sex of some reptiles determined by their genetic constitution (sometimes involving heteromorphic sex chromosomes) whereas in other species the animal's sex is determined by the environment (especially, incubation temperature)? Multiple phylogenetic transitions between genetic sex determination (GSD) and environmental sex determination (ESD) suggest that these alternative modes of sex determination possess adaptive significance. However, the selective forces favouring one versus the other remain obscure, despite sustained research in this field by many workers. The recent discovery of BOTH sex-determining systems simultaneously within a single population of alpine lizards provides a unique opportunity to test among competing hypotheses for the evolution of sex-determining systems. I propose an integrated study, in both the field and the laboratory, to clarify the mechanisms and the selective forces involved in the evolution of sex-determination.Read moreRead less
Evolutionary ecology of snakes and lizards. Although reptiles provide excellent "model systems" with which to examine evolutionary and ecological processes, most research in this field has been dominated by studies on other kinds of organisms. I propose a broad-ranging series of studies that will use a diverse array of lizard and snake species to erect and test novel hypotheses on the evolution of phenomena such as mating systems, sexual dimorphism, foraging biology, and reproductive investment ....Evolutionary ecology of snakes and lizards. Although reptiles provide excellent "model systems" with which to examine evolutionary and ecological processes, most research in this field has been dominated by studies on other kinds of organisms. I propose a broad-ranging series of studies that will use a diverse array of lizard and snake species to erect and test novel hypotheses on the evolution of phenomena such as mating systems, sexual dimorphism, foraging biology, and reproductive investment. My experimental studies will clarify the evolutionary role of phenotypic plasticity (that is, direct environmental effects) as well as genetic factors.Read moreRead less
Does adaptive plasticity play a significant role in the initial colonisation of novel habitats? An increased understanding of the evolutionary and ecological processes responsible for generating Australian biodiversity can facilitate effective management and conservation of this unique resource. Islands are especially significant in this context because they host many kinds of distinctive fauna and flora that have vanished from mainland habitats. It is therefore crucial to understand the biolo ....Does adaptive plasticity play a significant role in the initial colonisation of novel habitats? An increased understanding of the evolutionary and ecological processes responsible for generating Australian biodiversity can facilitate effective management and conservation of this unique resource. Islands are especially significant in this context because they host many kinds of distinctive fauna and flora that have vanished from mainland habitats. It is therefore crucial to understand the biology of these small isolated systems, as a way to preserve those unique systems as well as the distinctive evolutionary processes that occur within them.Read moreRead less
Heterarchical modelling of nutritional ecology: from individuals to communities. The project will combine advances in nutritional theory, agent-based modelling and landscape ecology to produce a modelling framework with which to understand the interrelationships between the physiology and behaviour of individual organisms and the populations, communities and ecosystems in which they reside. The resulting computational model will provide a major new initiative in quantitative ecology and allow sp ....Heterarchical modelling of nutritional ecology: from individuals to communities. The project will combine advances in nutritional theory, agent-based modelling and landscape ecology to produce a modelling framework with which to understand the interrelationships between the physiology and behaviour of individual organisms and the populations, communities and ecosystems in which they reside. The resulting computational model will provide a major new initiative in quantitative ecology and allow specific practical problems to be addressed in relation to agricultural pests, invasive species, conservation biology and animal production systems.Read moreRead less
Host plant choice by marine herbivores: ecological, genetic and historical constraints. Understanding the factors that determine plant choice by herbivores is crucial to predicting the ecological effects of herbivores on plants and herbivore adaptation to plants. This proposal aims to establish how evolution of host choice by a marine herbivore is constrained by ecological, genetic and historical factors. It will determine how the spatial arrangement of plants modifies host use, and whether evol ....Host plant choice by marine herbivores: ecological, genetic and historical constraints. Understanding the factors that determine plant choice by herbivores is crucial to predicting the ecological effects of herbivores on plants and herbivore adaptation to plants. This proposal aims to establish how evolution of host choice by a marine herbivore is constrained by ecological, genetic and historical factors. It will determine how the spatial arrangement of plants modifies host use, and whether evolutionary change by herbivores is constrained by genetic relationships among herbivore traits. The generality of important evolutionary hypotheses that predict plant choice by herbivores will be tested by extending such theory to new organisms and environments.Read moreRead less
Closing the loop: understanding the relationships between recreational fishing surveys, fishing regulations and fisheries management objectives. The project aims to improve the management of recreational fisheries in Australia by using model-based evaluations to understand the effects of recreational fishing regulations and survey design on the realisation and assessment of fisheries management objectives.
Putting sexual selection in a life-history context: What is meant by genetic quality? Theories of sexual signalling have been developed largely without reference to life-history theory and quantitative genetics. We will test recent theory that shows the costs of signals are best measured in units of future survival and reproduction. In a series of field and laboratory experiments on the cricket Teleogryllus commodus, we will test the idea that the "male genetic quality" referred to by good-genes ....Putting sexual selection in a life-history context: What is meant by genetic quality? Theories of sexual signalling have been developed largely without reference to life-history theory and quantitative genetics. We will test recent theory that shows the costs of signals are best measured in units of future survival and reproduction. In a series of field and laboratory experiments on the cricket Teleogryllus commodus, we will test the idea that the "male genetic quality" referred to by good-genes models of sexual selection is quality in the general ability to acquire resources, rather than in how resources are allocated among fitness components.Read moreRead less
Assessing the potential for and success of animal tranlocation: The Eastern Bristlebird as a case study. Translocation is set to become an important tool in the biodiversity conservation "toolbox", especially in securing species of small, cover-dependent, poorly dispersed passerine birds. Although there is a good theory for translocations, too few have been studied in detail to direct actions or predict outcomes. This project will develop a translocation methodology for the endangered Eastern Br ....Assessing the potential for and success of animal tranlocation: The Eastern Bristlebird as a case study. Translocation is set to become an important tool in the biodiversity conservation "toolbox", especially in securing species of small, cover-dependent, poorly dispersed passerine birds. Although there is a good theory for translocations, too few have been studied in detail to direct actions or predict outcomes. This project will develop a translocation methodology for the endangered Eastern Bristlebird and use detailed trapping and radio-tracking to determine the success of founder populations and the impacts of removing animals from source sites.Read moreRead less