The evolution of recombination cold spots during speciation. In the absence of geographic barriers, sexual reproduction between diverging populations is the greatest obstacle to the formation of new species. As diverging populations accumulate differences by the action of natural selection, genetic recombination resulting from sexual reproduction eliminates them. As a consequence, cases of speciation with gene flow such as sympatric or parapatric speciation have been considered improbable. This ....The evolution of recombination cold spots during speciation. In the absence of geographic barriers, sexual reproduction between diverging populations is the greatest obstacle to the formation of new species. As diverging populations accumulate differences by the action of natural selection, genetic recombination resulting from sexual reproduction eliminates them. As a consequence, cases of speciation with gene flow such as sympatric or parapatric speciation have been considered improbable. This project will investigate novel hypotheses for the formation of new species in the face of gene flow, and will evaluate empirically their predictions using the groundsel Senecio lautus. Results derived from this investigation will provide novel insights into the old riddle of speciation with gene flow.Read moreRead less
The genetics of replicated evolution. Using an Australian daisy, the project will study how natural selection creates repeated patterns of evolution at the gene and morphology levels. The project will provide students with training at the interface of genomics, ecology, and evolution.
Discovering sex determining genes in a reptile with genetic and environmental sex determination. Reptile sex determination is particularly fascinating because it is triggered either by genes on sex chromosomes or by the nest temperature. This project will identify and characterise candidate sex determining genes in a model reptile to understand how genes control sexual differentiation and how they interact with temperature.
Was an ancient bird-like sex chromosome system ancestral to reptiles and mammals? Recent discoveries reveal amazing similarity in the sex chromosomes of distantly related animals. This project will use advanced DNA technology to explore diverse sex chromosomes in reptiles to discover whether this signifies ancient and unsuspected common ancestry, or the convergent redeployment of genes and chromosomes predisposed to determine sex.
Expanding and resolving the earliest modern human divergence through DNA. This project aims to expand and resolve the earliest modern human divergence. Although it is clear modern humans emerged from Africa, there is no consensus on the timeline of modern human evolution. Archaeological evidence suggests two contenders: east and southern Africa. Genetic data supports the latter; the team’s own data shows that the southern African KhoeSan click-speaking forager peoples have the oldest extant huma ....Expanding and resolving the earliest modern human divergence through DNA. This project aims to expand and resolve the earliest modern human divergence. Although it is clear modern humans emerged from Africa, there is no consensus on the timeline of modern human evolution. Archaeological evidence suggests two contenders: east and southern Africa. Genetic data supports the latter; the team’s own data shows that the southern African KhoeSan click-speaking forager peoples have the oldest extant human lineages. This project will generate large mitochondrial genome and whole genome sequence data for KhoeSan lineages. This is expected to narrow the time of modern human emergence.Read moreRead less
Using population resequencing data to investigate the evolutionary role and functional impact of inversion polymorphisms. The project will use population re-sequencing data to generate high resolution haplotype maps of inversion polymorphisms in multiple human populations comprising more than 5,000 individuals. These maps will be used to impute inversion polymorphsisms in genotyped samples of more than 100,000 individuals, facilitated by development of novel algorithms for mapping inversion poly ....Using population resequencing data to investigate the evolutionary role and functional impact of inversion polymorphisms. The project will use population re-sequencing data to generate high resolution haplotype maps of inversion polymorphisms in multiple human populations comprising more than 5,000 individuals. These maps will be used to impute inversion polymorphsisms in genotyped samples of more than 100,000 individuals, facilitated by development of novel algorithms for mapping inversion polymorphism from population sequence data. Finally, the project will use this map to assess the functional impact and evolutionary role of inversions, by assessing their effect on quantitative traits and assessing measures of selection and population differentiation. Read moreRead less
The genomic landscape of speciation in hominins and other taxa. This project will develop a new analytical framework to build detailed genomic maps of speciation genes across different taxa, to determine whether observed speciation is the result of background selection and demography alone, or whether there are actual barriers to gene flow and introgressed DNA. The model will provide novel insights into the mechanistic basis of speciation, specifically whether a common set of genes or pathways a ....The genomic landscape of speciation in hominins and other taxa. This project will develop a new analytical framework to build detailed genomic maps of speciation genes across different taxa, to determine whether observed speciation is the result of background selection and demography alone, or whether there are actual barriers to gene flow and introgressed DNA. The model will provide novel insights into the mechanistic basis of speciation, specifically whether a common set of genes or pathways are central to the speciation process. The framework will be developed using the large genomic datasets available across a range of plant and animal species. Applying the model to a modern human population dataset will elucidate the role introgressed DNA from Denisovan and Neanderthals has played in shaping human evolutionary history and may provide novel insights into the genetic basis of disease.Read moreRead less
Haplodiploidy: the great evolutionary innovation of the Hymenoptera. This project aims to identify a key gene that causes thelytokous parthenogenesis. Thelytoky is the ability of a female to clone herself (virgin birth), and is wide spread in the Hymenoptera which include bees, wasps and ants. Hymenopteran thelytoky is important because it facilitates some major transitions in life history, particularly social parasitism. The capacity for virgin birth is central to the invasiveness of many ant s ....Haplodiploidy: the great evolutionary innovation of the Hymenoptera. This project aims to identify a key gene that causes thelytokous parthenogenesis. Thelytoky is the ability of a female to clone herself (virgin birth), and is wide spread in the Hymenoptera which include bees, wasps and ants. Hymenopteran thelytoky is important because it facilitates some major transitions in life history, particularly social parasitism. The capacity for virgin birth is central to the invasiveness of many ant species, and enables social cancers (parasitic workers that kill colonies) in bees. The benefit of this project is that the identification of the gene should help identify potentially invasive ant species and help prevent the social cancers that affect commercial beekeeping in South Africa from spreading world-wide.Read moreRead less
Evaluation of Bacillus amyloliquefaciens H57 as a probiotic in livestock using animal nutrition studies and metagenomics. To improve animal production, gene sequencing will unravel how microbial communities in the rumen of sheep and cattle and the gastro intestinal tract of poultry respond to feed quality and probiotic bacteria. The animal nutrition trials will also measure weight gain and feed utilisation efficiency, particularly for nitrogen, protein and energy.
Genomic signatures of adaptive diversification in woodland Eucalyptus. This project aims to map the sources of adaptive alleles underlying diversification is to reveal insights into the mechanisms of speciation. The source of the raw material for evolution can have significant impacts on the speed with which populations can adapt. An emerging pattern in speciation research is the importance of ancient alleles and introgressed genes, which differ in the genomic signatures left by selection. Eucal ....Genomic signatures of adaptive diversification in woodland Eucalyptus. This project aims to map the sources of adaptive alleles underlying diversification is to reveal insights into the mechanisms of speciation. The source of the raw material for evolution can have significant impacts on the speed with which populations can adapt. An emerging pattern in speciation research is the importance of ancient alleles and introgressed genes, which differ in the genomic signatures left by selection. Eucalyptus offers a unique opportunity to explore these modes of evolution using the latest genomic tools. Improving our understanding of adaptation and genetic variation in woodland eucalypts is expected to make a significant contribution to their conservation, management and restoration.Read moreRead less