- Evolutionary ecology research
- Australian rain forest community assembly
- Australian rain forest through time
- Ecology of Cumberland Plain Woodland
- Bicentenary Plant Diversity Program
- Biodiversity Adaptation Transect
- Botany of Botany Bay
- Conservation genetics
- DNA studies of Elaeocarpaceae
- Ecology of Isopogon prostratus
- Floristic Lists of NSW
- Habitat fragmentation
- Lomatia (Proteaceae)
- Molecular phylogeny of the Australian Lauraceae
- Promiscuous Lomatia
- Promiscuous Proteaceae
- Native plants of Sydney Harbour NP
- Newnes Plateau Shrub Swamps
- Next Generation Sequencing
- Nickel hyperaccumulation in Stackhousia
- NSW Vegetation Classification & Assessment Project
- Plants of the Newnes Plateau
- Plants, vegetation, landscape, country
- Phylogenetic relationships of Ceratopetalum
- Podocarpus elatus
- Rainforest conifer - Podocarpus elatus
- Speciation in Proteaceae
- Testing speciation models
- Horticultural research
- Plant diversity research
- Plant pathology research
- Herbarium & resources
- Scientific publications
Evolutionary patterns in the Proteaceae
Melita Milner - Ph.D. student Australia National University & Royal Botanic Garden, Sydney
Lomatia (Proteaceae) is a genus of 12 species, occurring in South America (3 species), eastern Australia (6 species) and Tasmania (3 species). Species distribution is mostly broadly sympatric, with several species often occupying the same region. This brings to question, was speciation allopatric (triggered by geographical isolation of populations) or sympatric (occurring in a continuous population).
Molecular data across all 12 species of Lomatia is being used to investigate genetic processes in the genus. The three South American species, despite overlap in distribution, are genetically distinct from each other. This suggests strong reproductive barriers are in place, preventing gene flow between species.
In contrast, Lomatia in Australia does not show a clear relationship between species and instead indicates there is extensive gene flow between species with a shared or proximate distribution.
Whilst some haplotypes are shared broadly across the distribution, suggesting ancestral remnants, others are restricted to a geographical area, indicative of more recent gene flow that has occurred following range expansion. Further evidence of recent gene flow is the apparent hybridisation which is rampant throughout Lomatia - wherever two species occur together, morphological intermediates can be found. This suggests speciation of Lomatia is due to vicariance events, however within Australia species range re-expansion and subsequent gene flow has occurred before reproductive barriers could establish.
Further work involving analysis of genetic and environmental data will allow us to determine dates of speciation, and how (or if) species boundaries are being maintained. This data will be compared with other genera, to determine common barriers and speciation events in the Australian flora.