Unlocking genetic diversity in fishes

We combine genetic techniques with traditional taxonomic methods to understand our marine fish fauna, how they have evolved and the effects of environmental pressures.

The Challenge

Applying genetic information

DNA is the genetic code for all living organisms.

Rapid developments in molecular techniques suitable for examining biodiversity are helping to unlock valuable genetic information from our biological collections.

For example, DNA can now be extracted from fish tissues such as white muscle, fin clips, scales, liver, larvae, eggs, tissue around vertebrae and otoliths and the vertebral cord.

By analysing DNA samples, we can gain a deeper understanding of:

  • how selection impacts genomes and leads to divergence and speciation
  • population structure and genetic connectivity of marine fish species

This is important for identifying risks to threatened and endangered species and to the sustainable management of fisheries.

Our Response

Harnessing molecular genetics and DNA barcoding analysis

We use the latest methods to extract genetic information from tissue samples.

Molecular genetics and DNA analyses are extremely powerful, because DNA is:

  • inherited
  • part of the cell
  • a permanent ‘marker’ which cannot be lost
  • can be analysed at any life cycle stage
  • generally not impacted by the environment.

DNA - and more importantly RNA - degrades after death, so tissue samples need to be collected and stored appropriately.

We are able to accurately assign specimens to species with the help of new methods, such as sequencing specific areas of the DNA genome (e.g. COI barcoding) alongside alpha taxonomy (which uses morphology and meristics).

We also use DNA markers such as microsatellites, single nucleotide polymorphisms and sequencing of genes/large sections of the genome, for the assessment of genetic connectivity among individuals, populations and species.

Molecular genetic identification

We are one of the largest and ongoing contributors of fish sequences to the international Barcode of Life initiative , and as part of the BioPlatforms Australia DNA barcoding initiative, we are developing framework datasets for Australian taxa.

Through the assembly of a standardised reference library of fish DNA barcodes, researchers provide important genetic information for both the research community and industry via:

  • accurately assigning specimens (eggs to adults, tissue fragments, prey, stomach contents etc) to species
  • undertaking rapid taxonomic surveillance of market or unknown samples
  • advancing the  genetic and ecological understanding of fish (which leads to more sustainable marine fish management) and
  • increasing our knowledge of the biodiversity of Australian fishes.

Molecular phylogenetics and connectivity of fish

We undertake molecular phylogenetic studies of key fish groups (i.e. wrasse and flatheads), which improve our understanding of historical evolutionary processes in Australian waters.

Our partners include the Commonwealth Environmental Research Fund, the National Environmental Research Program Marine Hub and Tree of Life Chondrichthyes project .

Additionally, using DNA from the ANFC, alongside material from other collections, researchers are:

  • developing a greater understanding of the genetic connectivity of marine fish species in domestic and international waters, which is important for the sustainable management of fisheries stocks and
  • identifying risks to threatened and endangered species.

Enquiries

Have an enquiry about this page?

Contact us

Interested in helping us further this research?

We seek research collaborators with complementary skills so we can work together for stronger results.

Contact us to collaborate