- Evolutionary ecology research
- Horticultural research
- Plant diversity research
- Amalie Dietrich project
- Australian freshwater algae
- Australian mesic zone biota
- Biology of Myrtaceae
- Cycad evolution and diversity
- DNA of ground orchids
- DNA studies of Restionaceae
- Evolution of Australian Utricularia
- Evolution of Proteaceae
- Fern biodiversity of Australia
- Key to the Lichen Genus Pertusaria
- Lamiaceae & Urticaceae
- Lepidoziaceae - southern liverworts
- Marine algae
- New Species and phylogeny in Restionaceae
- Phylogenetic biome conservatism
- Phylogeny and new species of Australian Utricularia
- Phylogeny of Orchidaceae tribe Diurideae
- Pollination studies in Prostanthera
- Project Camellia
- She-oaks - tough survivors
- Telopea special edition
- Theaceae of South-East Asia
- Trees of Papua New Guinea
- Tristaniopsis in south-east Asia
- Urticaceae of Java
- XVIII International Botanical Congress
- Plant pathology research
- Herbarium & resources
- Scientific publications
Aligning classification with phylogeny in the restiid clade of Poales
Barbara Briggs - Honorary Research Associate, Adam Marchant - Molecular Systematics Officer, Andrew Perkins
In studies of Australian species of plant family Restionaceae, and the related Anarthriaceae and Centrolepidaceae, an extensive program of sequencing chloroplast DNA has been completed. The data have been analysed to develop hypotheses of relationships. These are close relatives of the grasses and constitute the restiid lineage within the economically important major plant group, Poales.
Now that affinities are better known, it is clear that some of the genera currently recognised are polyphyletic, encompassing several species that are not closely related, or are paraphyletic, since other groups are embedded within them. As a result, changes are needed to produce a classification that accords with the evolutionary relationships but in which the genera may also be recognised by their morphological features. This involves enlarging Leptocarpus and Lepidobolus by combining several genera, so that fewer genera than in the present classification will be recognised.
The molecular data also give evidence that the Centrolepidaceae, which has long been recognised as a family, is embedded in Restionaceae and should instead be treated as a subfamily of Restionaceae. In appearance the miniscule centrolepid plants differ greatly from the much larger restiads, but they show resemblances to the seedling stages of restiad plants. Papers are being prepared to present the new data and conclusions, and to make the necessary changes in classification and nomenclature.
Descriptions have also been drawn up for nine new species, which have not previously been botanically named. They will be named in the genera that will be recognised when the classification is better aligned with the phylogeny, as a result of this study.
Assembling the monocot tree of life
Barbara Briggs and Gwen Harden - Honorary Research Associates
For several years Barbara has been part of an international collaboration to determine evolutionary relationships within the monocots worldwide. This has involved researchers in many centres in the USA, Canada and Australia. They have based their findings on analyses of data from the whole of the chloroplast genome. Most of the DNA extraction and sequencing was done in the USA, but this required the collection and sending of representative species from many countries. Some of the collections sent for study were from joint fieldwork in north-eastern NSW with Honorary Research Associate Gwen Harden. Alex Floyd of the North Coast Regional Botanic Garden at Coffs Harbour also assisted with the fieldwork.
The first major paper from this collaboration has now been published in the Annals of the Missouri Botanical Garden. This reported on analyses of 81 chloroplast genes in 83 species, representing the families of Poales and its relatives. This gives a clearer picture than previously possible of the relationships of the families, including determining the closest relatives of the grasses. It also shows that there have been five separate events in the evolution of Poales when lineages have shifted from insect pollination to wind pollination, with associated changes in the structure of the flowers. These evolutionary changes also appear to be correlated with changes in the predominant habitats. Studies of relationships of other monocot groups are continuing.