Project 4 - Small Terrestrial Vertebrates: Clarifying Taxonomic Status

The true diversity of many groups of Australia's mammals, reptiles and frogs is seriously underestimated by the current taxonomy which is still based largely on traditional, morphological assessments. Our goal is to promote a more systematic approach to the discovery of Australian vertebrate diversity through the combined use of molecular and morphological methods, with case studies selected across a range of different groups.

Challenges

Vertebrates such as mammals, frogs and reptiles are often thought to be taxonomically well known, with little need for further scientific collecting or taxonomic research. In Australia, this perception has been shattered over the last two decades by the discovery of high levels of genetic diversity in many widespread vertebrate species. Careful study of these groups almost always shows them to comprise multiple, partially overlapping species, often with contrasting ecologies and conservation status. Vertebrate diversity in Australia clearly is much higher than we currently think... but what groups are most seriously affected? And what are the best strategies and methods for documenting the hidden diversity?

The urgency of the problem is heightened for Australian mammals by the fact that many species are now very restricted in range due to the massive declines that occurred during the 19th and 20th centuries. For many of these species, we know little about their original geographic distribution and habitat preferences, and even less about the original pattern of genetic variation. Today, these gaps in knowledge hinder management of the surviving populations, and they also impede a growing interest in reintroduction programs as a way of rebuilding ecological communities and ensuring individual species survival. With the inevitability of further loss of small, isolated populations through random processes, the growing likelihood of climate change impacts, and the evidence of more general ongoing declines in the mammal fauna of northern Australia, there is real possibility that Australian mammals will experience a second wave of extinctions. This is a scenario that cannot be ignored.

Seeking solutions

All of our work uses a combination of molecular and morphological approaches to understand taxonomic diversity. Our focus is on adequate and effective approaches that lead to taxonomic resolution, and each project generally employs a slightly different set of methods or a different balance between morphology and molecules. For many of the projects, the study materials include historic and/or prehistoric specimens and these require special methods to extract and amplify the degraded 'ancient' DNA.

Benefits

The project will highlight the incomplete state of knowledge of Australia's unique and vulnerable vertebrate fauna, and provide case studies that illustrate how modern taxonomic approaches can lead to rapid improvements in knowledge and to improved decision making and management.