Community efficiency: testing MacArthur’s minimisation principle for competitive communities. Robert MacArthur, one of the 20th century’s greatest ecologists, developed theory that had profound impacts on our understanding of island biogeography, species coexistence, and competition, yet one of his most powerful theoretical predictions, that competitive communities should become more efficient over time, has never been tested. A greater understanding of the dynamics of community efficiency will ....Community efficiency: testing MacArthur’s minimisation principle for competitive communities. Robert MacArthur, one of the 20th century’s greatest ecologists, developed theory that had profound impacts on our understanding of island biogeography, species coexistence, and competition, yet one of his most powerful theoretical predictions, that competitive communities should become more efficient over time, has never been tested. A greater understanding of the dynamics of community efficiency will provide profound insights into the role of that community in the broader ecosystem, as well as strong predictions about the invasibility and stability of that community. Read moreRead less
Evolutionary signficance of sexual conflict in orb-web spiders. Multiple mating by females creates intense competition between ejaculates over the fertilisation of her eggs, and has a profound influence on male and female life history and mating strategies. In orb-web spiders, sexual cannibalism creates further conflicts of interest because the male may forfeit future matings. This project examines how life-history and mating strategies interact in these spiders, by identifying the mechanisms t ....Evolutionary signficance of sexual conflict in orb-web spiders. Multiple mating by females creates intense competition between ejaculates over the fertilisation of her eggs, and has a profound influence on male and female life history and mating strategies. In orb-web spiders, sexual cannibalism creates further conflicts of interest because the male may forfeit future matings. This project examines how life-history and mating strategies interact in these spiders, by identifying the mechanisms that determine the outcome of sperm competition; the selection pressures favouring sexual size dimorphism and male size variation; the influence of sexual cannibalism on male mating strategies; and the relationship between female feeding history and her mating behaviour.Read moreRead less
Senescence, sociality and sex. As individuals age, their body functions and survival prospects decline. Why some individuals deteriorate slower and later in life, is a critical question we cannot adequately answer, although the social environment has been suggested to be important. Using a recently established molecular biomarker of aging, this project aims to experimentally investigate in a wild bird if age-related decline is faster when individuals lack social support or face sexual competitio ....Senescence, sociality and sex. As individuals age, their body functions and survival prospects decline. Why some individuals deteriorate slower and later in life, is a critical question we cannot adequately answer, although the social environment has been suggested to be important. Using a recently established molecular biomarker of aging, this project aims to experimentally investigate in a wild bird if age-related decline is faster when individuals lack social support or face sexual competition. Expected outcomes are insights into key determinants of delayed aging and longer lifespan. Potential benefits include improved understanding of drivers of healthy aging, and improved ability to predict population persistence and identify conservation priorities. Read moreRead less
Constrained or strategic? Causes and consequences of variation in self-maintenance in wild birds. To live long and healthy lives, animals must defend themselves from diseases and repair damage due to wear and tear. This project will address what prevents animals from achieving optimal defences, and what the consequences are for ageing and survival.
Diadromous stream fishes: a model system for investigating sources of variation in recruitment. Our aim is to examine the relationship between adult abundance and recruitment in local populations of a diadromous stream fish to identify the source(s) of variation in recruitment. We will accomplish this by measuring larval production and recruitment among streams that vary in adult abundance, strength of settlement cues, and potential for larval dispersal. We will also use environmental markers of ....Diadromous stream fishes: a model system for investigating sources of variation in recruitment. Our aim is to examine the relationship between adult abundance and recruitment in local populations of a diadromous stream fish to identify the source(s) of variation in recruitment. We will accomplish this by measuring larval production and recruitment among streams that vary in adult abundance, strength of settlement cues, and potential for larval dispersal. We will also use environmental markers of larval origin to quantify the degree of self-recruitment and dispersal within/among populations. The results will broaden our understanding of the influence of local (production, habitat) versus regional (dispersal) processes to local population dynamics, information needed for effective stream management.Read moreRead less
Open or closed? Dispersal and recruitment in populations of aquatic invertebrates with spatially distributed resources. The general aim of this research is to examine the contribution of fertilised eggs and recently hatched juveniles to the local population dynamics of some stream invertebrates. It seems likely that these stages act as population 'bottlenecks' , and our research will quantify the relations between these two stages and between neonates and mature larvae. Our research will also ....Open or closed? Dispersal and recruitment in populations of aquatic invertebrates with spatially distributed resources. The general aim of this research is to examine the contribution of fertilised eggs and recently hatched juveniles to the local population dynamics of some stream invertebrates. It seems likely that these stages act as population 'bottlenecks' , and our research will quantify the relations between these two stages and between neonates and mature larvae. Our research will also indicate whether these populations are likely to be closed (i.e., groups of individuals are relatively isolated) along channels or not. We believe our results will show much stream research focuses on the wrong life-stages; practices of river management may need re-assessment.Read moreRead less
Can consistent individual differences in metabolic rate explain animal personality? Implications for fish and aquaculture in a warming climate. This project will determine if consistent individual differences in metabolic rate affect behaviour, growth, and reproduction in fish. If so, then we need to prepare for the fact that a warming climate will lead to reductions in fish growth and reproduction, because rising temperature directly increases metabolism and therefore maintenance costs.
Understanding individual differences in social behaviour: the role of personality. This project will investigate how behavioural differences, between individuals, influence key ecological decisions in social animals. The results will shed light on fundamental biological processes, with implications for such diverse applied areas as wildlife management, animal welfare and husbandry, pharmacology, disease risk and job satisfaction.
How does allocation to each sex evolve in hermaphrodites? New insight from the sea. Understanding the ability of hermaphroditic animals to adapt their sex allocation to suit environmental conditions will pave the way for integration between pure and applied research. Such understanding can provide stakeholders across a range of disciplines (natural resource management, aquaculture, conservation) with key information about genetic and environmental influences on the reproduction of many species o ....How does allocation to each sex evolve in hermaphrodites? New insight from the sea. Understanding the ability of hermaphroditic animals to adapt their sex allocation to suit environmental conditions will pave the way for integration between pure and applied research. Such understanding can provide stakeholders across a range of disciplines (natural resource management, aquaculture, conservation) with key information about genetic and environmental influences on the reproduction of many species of significant ecological, economic and social value with this mating system. This research will yield knowledge at the very forefront of evolutionary ecology, enhancing Australia's reputation for research excellence in this field, and further benefit Australian science through the training of young scientists.Read moreRead less
Are natural clones specialists or generalists? Using a model system to test alternative hypotheses for the advantages of parthenogenesis. Parthenogenetic organisms are all-female and reproduce clonally. Through discovering why these unusual organisms are sometimes successful we can better understand the significance of genetic diversity and sex. The Australian arid zone is a ?hot-spot? for parthenogenesis, with at least five independent examples including a native grasshopper and one of its host ....Are natural clones specialists or generalists? Using a model system to test alternative hypotheses for the advantages of parthenogenesis. Parthenogenetic organisms are all-female and reproduce clonally. Through discovering why these unusual organisms are sometimes successful we can better understand the significance of genetic diversity and sex. The Australian arid zone is a ?hot-spot? for parthenogenesis, with at least five independent examples including a native grasshopper and one of its host plants. I will apply modern molecular tools and ecophysiological techniques to test the hypothesis that parthenogenesis is favoured in this grasshopper because it allows the fixation of locally adapted clones. This research will provide a unique insight into the selective forces operating in the arid zone, Australia's largest ecosystem.Read moreRead less