Our lab works broadly in the area of plant evolutionary biology. Below are brief descriptions of some of our current projects.
Genomic consequences of polyploidy in plants
Polyploidy, or whole genome doubling, has been a significant evolutionary force in flowering plant history. We are studying different aspects of polyploidy using native New Zealand plant groups as well as the model polyploid system of Tragopogon (Asteraceae). Our aims are to understand the formation of polyploids and the genomic consequences of polyploidization in different plant lineages. In particular, we are studying polyploid diversification in relation to genome downsizing in native New Zealand plant species (e.g., Asplenium, Azorella, Libertia). This project is funded by the Marsden Fund (2018-2021) and is in collaboration with Bill Lee (Manaaki Whenua - Landcare Research), Heidi Meudt and Patrick Brownsey (Te Papa Tongarewa, The Museum of New Zealand), Dirk Albach (Carl von Ossietzky Universitšt Oldenburg), and Andrew Tanentzap (University of Cambridge).
Another major avenue of polyploidy research aims to address the potential conflict that arises in new polyploids between the duplicated nuclear genomes and the haploid maternally inherited organellar genomes (mitochondria and plastid). Successful interaction between the nuclear and cytoplasmic genomes is necessary to facilitate essential functions of growth and development (e.g., respiration and photosynthesis). This project was recently funded by the Marsden Fund (2019-2022) and is in collaboration with Murray Cox (Massey), Dan Sloan (Colorado State University), and Doug and Pam Soltis (University of Florida, Florida Museum of Natural History). We will soon be recruiting two PhD students to work with us on this project.†
Phylogenetic systematics of Malvaceae
Malvaceae is a large angiosperm family that includes economically important species such as cotton and Hibiscus. We are working on generic level phylogenies for different groups in tribe Malveae, which is the largest in subfamily Malvoideae, as well as tribe Hibisceae. Our focal genera are those from Australia and New Zealand (Asterotrichion, Gynatrix, Hoheria, Lawrencia, Plagianthus, and Hibiscus) and South America (Acaulimalva, Nototriche, and Tarasa). We are using molecular phylogenetic approaches to understand species relationships, biogeography, and character evolution within these groups, as well as using these phylogenetic frameworks to revise taxonomy when needed.
Evolution and conservation of native New Zealand flora
The New Zealand flora is incredibly diverse and unique with a high proportion of endemic species. Many of these species are endangered or threatened because of historical loss of native habitat. In collaboration with Vaughan Symonds (Massey) and Alastair Robertson (Massey), we are studying the population and conservation genetics of these native plant groups. Some of our focal genera include Dactylanthus (Mystropetalaceae), Fuchsia (Onagraceae), Korthalsella (Viscaceae), Myosotis (Boraginaceae), Selliera (Goodeniaceae), and Sophora (Fabaceae). Most of these projects have been conducted by MSc and PhD students.