I am a conservation biologist at Charles Darwin University. Research in my group uses genetic and ecological information to understand how animal populations work and how they respond to environmental change.
In recent years, much of our work has addressed the effects of fire regimes on animal and plant populations. Combining genomics and field ecology has provided new insights into how populations respond to fire, as well as improving our understanding of landscape genetics patterns and processes in disturbance-prone ecosystems.
Another core theme is the use of genetics and field-based methods to understand animal movement across the landscape (or riverscape and seascape in the case of crocodiles!). We have developed and evaluated methods for understanding dispersal patterns from genetic data and use these approaches for ecological and conservation-focussed research.
Recent papers and other things
How do fire and logging affect soils?
Elle Bowd's recent PhD paper in Nature Geoscience revealed the temporal duration of effects of disturbances like fire and logging on soil in montane ash forests. She found that, even eight decades after disturbance, disturbed soils had lower values of a range of ecologically-important attributes like available nitrates and phosphorus than 'old growth' forest that had not been disturbed for over 150 years. Sites subject to compounding disturbances such as salvage logging displayed the most intense impacts.
Genetic structure of the world's tallest angiosperm
Brenton von Takach Dukai published a paper from his PhD showing almost-ubiquitous hybridisation between maountain ash (Eucalyptus regnans) and other eucalypts. The paper discusses the implications of different processes driving genetic structure for genetic management of forestry-related restoration efforts. The paper is available for free in Evolutionary Applications.
Can genetic monitoring of effective population size indicate demographic population trends?
Jenny Pierson led a new paper just published in Evolutionary Applications, in which we used long-term empirical data on abundance and genetically-estimated effective population size (Ne) to determine whether Ne can be used as an indicator of population size changes. There is a lot of excellent theoretical work in this space and our interest was to see how the patterns play out with empirical monitoring on mammals including bears, possums and antechinus. The answer was "Yes, but...".
Sex, dispersal and genetic structure in mammals
Robyn Shaw's fantastic paper on how mammalian mating systems and dispersal behaviour influence spatial genetic patterns at genetic markers with different inheritance modes is now online in Molecular Ecology.
Using quadratic entropy to estimate genetic diversity within and among populations
I was lucky enough to work with Peter Smouse and Rod Peakall on a recent paper in PLoS ONE describing the use of Rao's quadratic entropy to develop metrics of diversity within and among populations from genetic distance data. Since equations don't make for an appealing website image (sorry Peter) I've added a pic of the case study species, the rather cool brown antechinus (pic by Stephen Mahony).
Incorporating fire-driven environmental variability in landscape genetics
Landscape genetics has led to many discoveries about patterns of connectivity of populations. Geoff Cary, Ian Davies and I recently published a paper in Molecular Ecology in which we used simulation models to understand how variation in long-term fire regimes across the landscape can influence neutral and adaptive genetic diversity. Where predictable fire regimes (e.g. refuges or fire-prone 'hotspots') occurred due to environmental factors like topography, there was strong spatial variability in genetic diversity. This research shows how refuges can be important for maintaining genetic diversity in landscape characterised by heterogeneous fire regimes, and demonstrates how processes other than population connectivity can influence landscape genetics patterns.