In the first week of semester I had the opportunity to accompany several researchers on a field trip to Narrabri, in north western New South Wales. This field trip was one component of a project involving the collaboration of researchers from Harvard University, the University of Canberra, and the Australian National Wildlife Collection (ANWC), CSIRO.
A recent study (Burley, 2017) has identified a chromosomal rearrangement unique to the honeyeater (Meliphagidae) family. As such, the overall aim of the current project was to further understand the evolution and consequences for gene expression of this unique chromosomal system which has evolved in Australian songbirds.
To address this, field work was conducted to obtain relevant tissues suitable for establishment of cell lines and chromosomal and genetic analysis from various honeyeater (Meliphagidae) and thornbill (Acanthizidae) species. Laboratory work was then to be conducted using in situ hybridisation to determine the physical location of gene sequences on specific chromosomes.
To document the species harbouring chromosomal arrangements, voucher specimens were prepared for deposition in the ANWC (CSIRO) and the Museum of Comparative Zoology (Harvard, USA). These specimens provide reference anchor points for all future analyses of the data derived from the specimens; an extremely important point, in the case that something unexpected is found.
Significance of this study
Research of this nature, such as studying how the genomes of non-human animals evolved is vital in order to put in context how humans and other vertebrates evolved, and how bird evolution is unique relative to other vertebrates. As these data will improve the understanding scientists have of the basic structure of genomes of Australian songbirds, they may prove vital in the genetic management of endangered honeyeaters and songbirds.
Simply knowing where genes are located in the genome helps scientists understand how such species are manipulating genetic diversity. Understanding the taxonomic scope and prevalence of chromosomal rearrangements is one way to help researchers interpret the results of genetic surveys of diverse species, which in turn will be crucial in future species conservation efforts.
An example demonstrating the importance of such data in the context of conservation, is the recent research and subsequent publications by Dolman and Joseph which led to the split of one avian species, into two distinct species. The Chestnut Quail-thrush (Cinclosoma castanotum) was split into two species, C. castanotum and the Copper-backed Quail-thrush (Cinclosoma clarum). As such, any conservation and management strategies can be implemented as appropriate with respect to the relevant Cinclosoma species.
A tour of the Australian National Wildlife Collection (ANWC)
Upon arrival back in Canberra, I was invited into the ANWC where the collection manager guided me around the collection. I was able to observe just a small fraction of the many thousands of specimens the ANWC holds, and I gained a huge appreciation of the scientific value each specimen and its associated data.
It was here that I was informed just how large this collection is, and of its great importance, as it is a vital archive for the research and conservation of Australia’s terrestrial vertebrate biodiversity.
This collection holds almost 200,000 irreplaceable specimens which represent 99% of Australian birds, 75% of Australian mammals, 60% of Australian reptiles, 70% of Australian amphibians. The ANWC is also the leading repository for heritage egg collections, holding eggs from over 1000 species.
Importance of biological collections for conservation
Natural research collections dating back to the late 1700’s, underpin a significant amount of research conducted by Australian and international scientists on taxonomy, population genetics, biogeography and ecology.
CSIRO has several federally gazetted natural history collections, which are a fundamental scientific resource and are pivotal for biodiversity conservation and management. These include the ANWC, the Australian National Insect Collection (ANIC), the Australian National Herbarium (ANH), and the Australian National Fish Collection (ANFC).
Today, the ANWC is revealing how birds are responding to climate change, and importantly holds irreplaceable records for historical species distributions for restoration projects.
ANIC contributes to protecting Australia’s biodiversity, enabling the identification of insects at Australia borders, while also revealing how insecticide resistance develops.
ANH supports threatened species recovery and weed seed identification at the Australian borders.
Without these natural research collections, much of what we know about Australia’s biodiversity including evolution, and population genetics would not have been possible and as such the conservation status of many species may not have been established; only time will tell what is yet to be discovered.
Burley, J. (2017). ‘Reticulate Evolution of an Australo-Papuan Songbird Inferred Using Whole-genome Sequencing.’ (M.Sc. thesis, Uppsala University: Uppsala.)