Population divergence and the thermal ecology of sexual conflict. This project aims to test how populations of introduced mosquitofish have adapted to local differences in water temperature (such as Tasmania versus Queensland). To what extent has natural selection (for survival) and sexual selection (the ability of males to acquire mates and/or females to resist unwanted matings) driven the local adaptation of populations? Many species have traits that evolve under intense sexual conflict – nota ....Population divergence and the thermal ecology of sexual conflict. This project aims to test how populations of introduced mosquitofish have adapted to local differences in water temperature (such as Tasmania versus Queensland). To what extent has natural selection (for survival) and sexual selection (the ability of males to acquire mates and/or females to resist unwanted matings) driven the local adaptation of populations? Many species have traits that evolve under intense sexual conflict – notably when males harass or coerce females into mating and females resist these attempts. It is assumed that sexual conflict traits are rarely affected by the local environment. The project will test the hypothesis that temperature can actually drive the evolution of such traits, specifically coercion and resistance to mating.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
Life history constraints on sexual selection: an investigation using territoriality in butterflies. Contemporary studies into the evolution of male contest behaviour largely ignore the influence of life history. However, contest behaviour should be influenced by life history because the costs of fighting (injury or death) are extracted in a life history currency. Here I aim to measure reproductive value in a territorial butterfly, and to isolate the effects of this parameter, physiological condi ....Life history constraints on sexual selection: an investigation using territoriality in butterflies. Contemporary studies into the evolution of male contest behaviour largely ignore the influence of life history. However, contest behaviour should be influenced by life history because the costs of fighting (injury or death) are extracted in a life history currency. Here I aim to measure reproductive value in a territorial butterfly, and to isolate the effects of this parameter, physiological condition and fighting experience upon male aggression. I propose an innovative experimental approach to unraveling the effects of these covarying life history influences which promises exciting and highly original insights into the evolution of contest behaviour.Read moreRead less
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
The role of plant chemical defences in the population ecology of mammal herbivores. Plants defend themselves against herbivores by producing toxic compounds in their leaves. Many studies show that such compounds influence diet selection by mammal herbivores, but we understand much less about their effects on populations of such species. This project will investigate how concentrations of leaf toxins in eucalypts affect reproductive success, distribution and abundance of the marsupials that feed ....The role of plant chemical defences in the population ecology of mammal herbivores. Plants defend themselves against herbivores by producing toxic compounds in their leaves. Many studies show that such compounds influence diet selection by mammal herbivores, but we understand much less about their effects on populations of such species. This project will investigate how concentrations of leaf toxins in eucalypts affect reproductive success, distribution and abundance of the marsupials that feed on them. The knowledge gained by this study will be important in modelling populations of these marsupial species and predicting their responses to environmental change.Read moreRead less
Can inbreeding avoidance cause the evolution of sex-biased dispersal? This project aims to combine unique long-term data with a novel Citizen Science approach to seek to provide the first complete test of the hypothesis that inbreeding avoidance can cause one of the best known patterns in mammal and bird societies - sex differences in when and how far juveniles disperse. Dispersal is a critically important ecological and evolutionary process, as it influences the fate of populations, and also de ....Can inbreeding avoidance cause the evolution of sex-biased dispersal? This project aims to combine unique long-term data with a novel Citizen Science approach to seek to provide the first complete test of the hypothesis that inbreeding avoidance can cause one of the best known patterns in mammal and bird societies - sex differences in when and how far juveniles disperse. Dispersal is a critically important ecological and evolutionary process, as it influences the fate of populations, and also determines the individuals with which a disperser will spend the remainder of its life. It therefore shapes the likelihood that kin will interact to cooperate or compete, and determines the pool of individuals with which the disperser can mate.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.
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
Threshold traits: conditionality, instability and broken symmetry. This project will use experimental evolutionary ecology to understand biological switches that are tripped in response to environmental change. This will increase knowledge of how the environment affects organisms; exploring the limits to diversity on the one hand and the generation of novelty on the other.
Native fish stocking of rivers: discriminating between hatchery-reared and wild fish. Stocking of fish is widely used in attempts to restore native fish populations. Little is known of the fate of stocked fish or the effects of stocking on resident populations. We will develop and evaluate protocols for chemical marking of otoliths of hatchery-reared fish so that their source can be determined. Experimental stocking of hatchery-reared fish will be undertaken and population structure and sourc ....Native fish stocking of rivers: discriminating between hatchery-reared and wild fish. Stocking of fish is widely used in attempts to restore native fish populations. Little is known of the fate of stocked fish or the effects of stocking on resident populations. We will develop and evaluate protocols for chemical marking of otoliths of hatchery-reared fish so that their source can be determined. Experimental stocking of hatchery-reared fish will be undertaken and population structure and source of stocked versus wild fish determined in stocked and unstocked rivers. Natural chemical signatures will also help determine important recruitment areas. The outcomes will allow fisheries managers to make informed decisions regarding stocking strategies.Read moreRead less