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
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
The evolution of parental care in leeches: costs and benefits in a clade of hermaphroditic, invertebrate ectotherms. Parental care is a basic element of reproduction in many species. Nearly everything we know about parental care comes from study of vertebrates, especially birds and mammals. Leech is synonymous with exploitation, but many of these annelid worms are devoted parents. Because they differ dramatically from most vertebrates, leeches present an excellent, but as yet unused, opportunity ....The evolution of parental care in leeches: costs and benefits in a clade of hermaphroditic, invertebrate ectotherms. Parental care is a basic element of reproduction in many species. Nearly everything we know about parental care comes from study of vertebrates, especially birds and mammals. Leech is synonymous with exploitation, but many of these annelid worms are devoted parents. Because they differ dramatically from most vertebrates, leeches present an excellent, but as yet unused, opportunity to test our theories and understanding of the evoluton of parental care. We will examine the evolution of degrees of care and sibling competition in leech families, and use molecular markers to better understand the genetic structure of populations of these invertebrates.Read moreRead less
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
Sex, parthenogenesis and adaptation: a novel laboratory 'natural selection' experiment testing the adaptive significance of sexual and asexual reproduction. One of the greatest challenges for evolutionary biology is explaining the widespread occurrence of sexual reproduction. Many theoretical models show some inherent benefits of sex, however these models make assumptions that little or no empirical data exists for. Using a novel phenomenon found in the parasitoid wasp genus Trichogramma, I will ....Sex, parthenogenesis and adaptation: a novel laboratory 'natural selection' experiment testing the adaptive significance of sexual and asexual reproduction. One of the greatest challenges for evolutionary biology is explaining the widespread occurrence of sexual reproduction. Many theoretical models show some inherent benefits of sex, however these models make assumptions that little or no empirical data exists for. Using a novel phenomenon found in the parasitoid wasp genus Trichogramma, I will investigate the adaptive significance of sexual and asexual reproduction in a laboratory natural selection experiment and therefore directly test the theory for the evolution and maintenance of sex. This will be the first such test in a higher organism.Read moreRead less
Connectivity and movements of large pelagic species of ecotourism value. The project aims to answer key questions about the biology, ecology and sustainability of the world’s manta ray species to provide the information and tools for management and conservation of these charismatic and valuable species. In particular, the project aims to determine the likely impact of climate variability and fisheries that operate to Australia’s north on manta-based ecotourism in the Indo-Pacific region, as clim ....Connectivity and movements of large pelagic species of ecotourism value. The project aims to answer key questions about the biology, ecology and sustainability of the world’s manta ray species to provide the information and tools for management and conservation of these charismatic and valuable species. In particular, the project aims to determine the likely impact of climate variability and fisheries that operate to Australia’s north on manta-based ecotourism in the Indo-Pacific region, as climate change and active low-value fisheries may both jeopardise a high-value ecotourism industry. The project seeks to explore geographic distributions, local and large-scale movements, population sizes, structure, and inter-connectivity in the region to assess the effect of climate and fisheries on manta ray populations.Read moreRead less
Diet influences the selective advantage of mitochondrial DNA mutations. This project aims to examine critical mechanisms that affect mitochondrial DNA variation within species. It aims to test the hypothesis that mitochondrial DNA haplotypes have the potential to be under nutritionally induced balancing selection as a consequence of cellular signalling and/or Adenosine triphosphate (ATP) production by mitochondria. Diet can vary both seasonally and geographically and is a key environmental param ....Diet influences the selective advantage of mitochondrial DNA mutations. This project aims to examine critical mechanisms that affect mitochondrial DNA variation within species. It aims to test the hypothesis that mitochondrial DNA haplotypes have the potential to be under nutritionally induced balancing selection as a consequence of cellular signalling and/or Adenosine triphosphate (ATP) production by mitochondria. Diet can vary both seasonally and geographically and is a key environmental parameter that influences the ability of a species to colonise new habitats. The project plans to characterise the functional links between specific mitochondrial DNA haplotypes, mitochondrial functions and organismal traits. The expected outcome is a more precise grasp of the processes influencing genetic variation within and among species, which would inform current issues in ecology and genetics.Read moreRead less
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.
Discovery Early Career Researcher Award - Grant ID: DE120102323
Funder
Australian Research Council
Funding Amount
$375,000.00
Summary
How the visual environment affects the diversity of avian colours and why this matters. Evolutionary theory predicts that (a) animal colours are optimised to perform best in their native environment and hence that (b) environmental degradation can disrupt the function of animal colours in communication or camouflage. This project will test these predictions for Australian birds and use the outcome to inform environmental restoration programs.