Dr. Dan Edwards

Postdoctoral Research Associate (with Assoc. Prof. Scott Keogh)

The Australian National University

Background and Research Interests

I have a long standing interest in the conservation, natural history and evolution of herpetofauna. I began initially by studying Honours with Assoc. Prof. Mike Mahony and Dr. John Clulow at The University of Newcastle, looking at the reproductive biology of The Spotted Grass Frog, Limnodynastes tasmaniensis. The goal of this research was to set up the framework for this very common species to be used as a model in the development of assisted reproductive programs for the conservation of amphibians. While this area satisfied my need for conservation based research, opening up an important avenue needed to assist the maintenance of genetic diversity in the face of the global amphibian crisis, sitting in a lab looking at eggs, sperm and developing embryo's just didn't do it for me.

I began to be interested more in finding out what genetic diversity existed and how it evolved in various biogeographic regions, with the idea that if we know this before species become threatened, we better know how to conserve them. Enter phylogenetics, phylogeography and population genetics. My PhD, with Prof. Dale Roberts at The University of Western Australia (doing all my lab work at The Australian National University with Assoc. Prof. Scott Keogh), started me on the journey with molecular ecology. Southwestern Australia is a biodiversity hotspot of global importance due the immense diversity, large amount of endemicity and serious human habitat modification. What also makes it interesting from an evolutionary perspective is the understudied animal diversity, particularly in the Myobatrachidae. I compiled comparative phylogeographic (Crinia georgiana, Metacrinia nichollsi, Geocrinia leai and Arenophryne rotunda) and population genetic (Spicospina flammocaerulea, A. rotunda, M. nichollsi and C. pseudinsignifera) datasets. What I found was that climate fluctuations (and geology in the case of A. rotunda and a soon be named new Arenophryne species) from the Miocene to the present shaped the evolution within southwestern Australian frogs. The northwestern and southeastern coastal regions of the southwest were highlighted as important for genetic diversity, as in the endemic flora. Also across the extreme mesic and relictual southwestern coastal area refugial zones associated with drainage systems provided deep and congruent divergences within some species previously thought to be continuously distributed. The most concerning thread throughout the various studies was the impact that future climate change is going to have on these species, particularly given the patterns of habitat modification in modern day southwestern Australia.

I also did a research internship with Dr Jane Melville at Museum Victoria, which was focussed on compiling phylogeographic datasets for the morphologically diverse agamids, Diporiphora australis and Amphibolurus nobbi. This work took me on a mammoth remote field trip through the Kimberly, NT and the Gulf and Southern Cape regions, throughout QLD and central NSW. The interesting results from this work showed that congruent phylogeographic breaks seen in the well-studied wet tropics biota also existed in my dry woodland agamids. I was also able to rule out the notion that D. australis was a species complex, yet this was certainly not the case with Am. nobbi. I am currently preparing this work for publication.

My current and future research objectives focus on biogeography, speciation and dispersal capabilities across a variety of herpetofauna, and may also include other taxa in the future. I am interested in many areas of molecular ecology and evolution, covering the disciplines of population genetics, phylogeography and phylogenetics. I am particularly interested in understanding the climatic, ecological and life history influences on an animals' ability to move through the landscape and the impacts these factors have over evolutionary time on a biogeographic scale. I am also interested in the evolution of endemism and its genetic consequences. I believe this sort of research is an important frontier for the conservation of all taxa in the face of ongoing climate change and habitat destruction.

I am currently a Postdoctoral Research Associate in Assoc. Prof. Scott Keogh's Lab at The Australian National University, working on the biogeography of southwestern Australian reptiles.

Education

• 2007 PhD. The University of Western Australia (supervised by Prof. Dale Roberts). Biogeography and speciation of southwestern Australian frogs.
• 2001 B. Env. Sc 1st Class Honours. The University of Newcastle. Studies of reproduction in Limnodynastes tasmaniensis.
• 1998 - 2000 B. Env. Sc. (Biology Major), The University of Newcastle.

Professional Experience

• 2007 - onwards Postdoctoral Research Associate. Supervised by Assoc. Prof. Scott Keogh, I will be working on the biogeography of various southwestern Australian reptile species.
• 2006 - 2007 Research Assistant. Research Assistant completing molecular genetics lab projects on various herpetofauna for Assoc. Prof. Scott Keogh at The Australian National University.
• 2005 - 2006 Research Internship. Supervised by Dr Jane Melville at Museum Victoria involving remote area field collection of many different agamid species, field supervision of an Honours student and molecular lab work. My specific project was on the phylogeographic structure in the morphologically diverse species, Diporiphora australis and Amphibolurus nobbi.
• 2002 - 2003 Tutor and Demonstrator. Tutor and demonstrator for first year Biology classes at The University of Western Australia.
• 2001 - 2002 Field Tutor and Assistant. Field tutor and assistant for Assoc. Prof. Michael Mahony during several Earth Watch trips focussing on ecological and demographic research on stream frog communities along the northern NSW coast, with particular focus on species in the Mixophyes genus.
• 2001 Tutor and Demonstrator. Tutor and demonstrator for the second year class Animal Physiology at The University of Newcastle.

Fellowships, Research Grants, Awards

• 2007, PhD awarded with Distinction
• 2004 - Australian Society of Herpetologists Student Grant (AU$550).
• 2003 - Australian Geographic Grant (AU$2,000).
• 2002 - Department of Conservation and Land Management Western Australia one off Grant (AU$8,000).
• 2002 - Federal Department of Agriculture, Forestry and Fisheries Australia (AFFA) Awards for Young Scientists (Land and Water Australia Award) (AU$8,000).
• 2002 - Australian Postgraduate Award and Stipend. The University of Western Australia (3 years).
• 2000 - Dean's Commendation List. The University of Newcastle.

Publications

Browne, RK and Edwards, DL (2003) The effect of temperature on growth and development of green and golden bell frogs (Litoria aurea). Journal of Thermal Biology 28: 295-299. Download PDF.

Edwards, DL, Mahony, MJ and Clulow J (2004) Effect of sperm concentration, medium osmolality and oocyte storage on artificial fertilisation success in a myobatrachid frog (Limnodynastes tasmaniensis). Reproduction, Fertility and Development 16: 347-354. Download PDF.

Edwards, DL, Roberts, JD and Keogh, JS. 2007. Impact of Plio-Pleistocene arid cycling on the population history of a southwestern Australian frog. Molecular Ecology 16:2782-2796. Download PDF.

Edwards, DL. 2007. Biogeography and speciation of a direct developing frog from the coastal arid zone of Western Australia. Molecular Phylogenetics and Evolution 45: 494-505. Download PDF.

Doughty, P, Edwards DL. A new species of Arenophryne (Anura: Myobatrachidae) from the central coast of Western Australia. Records of the Western Australian Museum. In Press.

Submitted Manuscripts

Edwards, DL, Roberts, JD and Keogh, JS. Climatic fluctuations shape the phylogeography of a mesic adapted direct developing frog from the southwestern Australian biodiversity hotspot.