Botanic Gardens Trust, Sydney, Australia

Fern biodiversity of Australia

Dr Nathalie Nagalingum - Systematic Botanist
From the forest floor to their canopies, and from coastal fringes to the desert inland, ferns are a critical component of Australia’s biodiversity. Ferns are also familiar and loved plants in our homes and gardens: a few examples include tree ferns (Cyathea spp. and Dicksonia spp.), bird’s nest fern (Asplenium australasicum), and maidenhair ferns (Adiantum spp.). In Australia, there are more than 450 species of naturally occurring ferns, and of these two-thirds are native. 

Updating Australian fern classifications using genetic trees

By leveraging recent discoveries in molecular techniques and fern taxonomy, Dr Nathalie Nagalingum is providing an updated understanding of classification of Australian fern species. Through extensive collections of ferns being obtained during her fieldwork in Queensland and New South Wales, she will be using state of the art molecular techniques and analyses to produce genetic 'family trees' for all of the collected species and present updated classifications of the ferns of Australia. 

Recent molecular studies - a necessity for species classification and identification - have lacked Australian fern representatives. Since the species is the fundamental unit of biodiversity research, this work will have ramifications on studies in evolution, ecology and conservation biology. More specifically, this research is critical to fern conservation since it will result in revision of current traditional classifications into a modern, genetic framework for our fern species. Similar work has revolutionised the classification of important Australian groups such as Acacias and Eucalypts, and this work has the potential to transform our understanding of Australian ferns as well.

Providing a DNA barcodes for species identification

In addition to improved classification, Nathalie Nagalingum, through her research, aims to provide DNA barcodes for all Australian tropical ferns. DNA barcoding is an emerging tool that will only be possible as scientists provide the relevant DNA barcodes and species identification as reference points. This project is the first attempt at barcoding Australian ferns and is the largest of its kind - the only region in the world where there are fern barcodes is NW Europe where there were only ~40 species barcoded. 

Barcodes are already being collected for other organisms in Australia, such as fish, insects, grasses and trees of the Wet Tropics, and the inclusion of ferns significantly expands the breadth of this promising tool of the future.

In the long-term, such DNA barcodes will be an asset to biodiversity management. For example, Nathalie has been involved in a project in Florida where barcoding was used to determine that an unidentifiable Marsilea (lacking in diagnostic reproductive features) was a new species, and not an invasive non-native species as first thought. As a result the management of the fern has shifted from potential eradication to conservation. The DNA barcodes, which will be generated from Nathalie’s work, will provide a means for protecting biodiversity by allowing stakeholders the ability to: conduct rapid biodiversity surveys, identify and manage invasive weeds that threaten future landscapes particularly as the climate changes, and protect Australia’s biodiversity through giving quarantine the ability to identify unknown species.

Appreciating the ferns of Australia through living plants

Nathalie Nagalingum is working with Maureen Phelan who is the horticulturalist in the Sydney Fernery to produce updated signage and provide spores that will be propagated into mature plants. They hope to encourage the appreciation of ferns through these educational displays and significantly expand the horticultural collections in the Sydney Fernery in the Royal Botanic Garden, Sydney.

Dicksonia antarctica
 - the Dandenongs, Victoria

tree fern
Cyathea cooperi
, Cairns Botanic Gardens, Queenlsand

Cyathea rebbecae
, Barron Gorge National Park, Queensland

All Photos: N Nagalingum