Botanic Gardens Trust, Sydney, Australia

Fern and gymnosperm research

Dr Nathalie Nagalingum - Research Scientist

Patterns of fern diversity and endemism in Australia

Together with collaborators from the Centre for Australian National Biodiversity Research and the University of California, Berkeley, patterns of fern diversity and endemism have been examined across the entire continent of Australia. To do this standard taxon-based metrics (counts) as well as phylogenetic indices have been used.
Ferns have a wide range of habitat preferences and are widely distributed, and because of this are an ideal group for understanding how diversity and endemism are distributed. Most of our knowledge of fern distributions derives from transects, and overall there are few synthetic studies over large regions.

Australia is an ideal study area because the continent encompasses a broad range of habitat types allowing an understanding of the relationship between diversity and endemism in various environments. In addition, the completed floristic treatment of the ferns in the Flora of Australia 15 years ago has provided a standardised taxonomy across all states. The Australia's Virtual Herbarium (AVH) project has mobilised collection data from all the herbaria in the country andas a result, distributional data of all Australian specimens have been digitised and are available for analysis. After error checking and updating the taxonomy, the distributional data consisted of over 60,000 records.

At the same time, I constructed a phylogeny of three molecular markers for all 89 Australian fern genera. Downloaded sequences were used from the online data repository Genbank as well as generating new sequences in the molecular laboratory.

Preliminary results of this research were presented in late 2012 at Chicago Botanic Garden, French National Institute for Agricultural Research, Bordeaux (INRA), and University Paris-Sud, Orsay. In July 2013, I will be giving a presentation on the final results at the Botanical Society of America meeting. This work is currently being prepared for publication.

Phylogenetic diversity and endemism in Australian conifers

In mid-2012, University of California, Berkeley student Annasophie Lee, spent three months working with me as part of her honors project. During this time Annasophie worked in the molecular lab extracting DNA and conducting PCRs of Australian conifers, and generated a preliminary phylogeny. She also used the AVH to obtain the conifer distribution data. Annasophie is currently writing up her honors thesis on 'Phylogenetic diversity and endemism in Australian conifers', and will also be presenting her findings at the Botanical Society of America meeting.


Cycad stem ferns in Queensland rainforest

Filmy fern in Queensland rainforest

Gleichenia - Jervis Bay

All photos: Nathalie Nagalingum