DNA & Its Applications in Nature

August NSB Meeting

In the past it would have been called science fiction, today it is referred to as cutting-edge research, tomorrow it will be the norm!

This is possibly the best way of summarising the information delivered by our speaker, Dr Olly Berry, leader of CSIRO’s Environomics Future Science Platform, whose mission is to develop better scientific tools to support natural resource management in Australia and elsewhere.

Environomics—short for environmental genomics—is a technology platform to see beyond the landscape to its ‘genescape’, to reveal and make use of its genetic resources. The information obtained from genomics (the branch of molecular biology concerned with the identity, condition and function of genomes) is reinventing how we measure ecosystem health, change and threats. It can also lead to the finding of new ways to solve problems and to finding new resources in nature.

By way of introduction, Olly related the story of how eDNA (essentially the DNA of flora or fauna) was used to investigate the cause of the sudden decline in the Woylie population after the significant reduction of the primary predator, the Red Fox, by a baiting program. As every species and every individual of that species has a unique DNA code, it was possible to analyse hairs found on the collars of dead Woylies that still had their radio transmitters attached. This clearly showed that cats had filled the void left by foxes and were now the chief predator.

As for the future, CSIRO is just one of many institutions around the world with vast natural history collections that can be used as the starting blocks for transitioning into digital catalogues that can be coupled with genomics to help identify, understand and manage biodiversity.

Some of the projects being undertaken by the Environomics FSP team are:

  • understanding stress in Australia’s animals and plants
  • online species maps from environmental DNA
  • mapping pollinator networks.

One of the exciting aspects of FSP is the employment of early career researchers who are developing new skill sets as they seek to develop new techniques.

Olly showed us examples of research being undertaken in Western Australia. Flavia Tarquino is testing whether seagrass restoration can be improved by manipulating the bacterial communities that naturally coexist in their seeds, leaves and roots.

In another example, a CSIRO team showed how eDNA can be used to speed up biodiversity monitoring. In this case, determining the number of fish species around Browse Island. Traditional methods such as physical observation or studying underwater videos were compared with sampling water for eDNA. The eDNA detected 210 species, compared to 99 seen on more than 100 hours of videos. Seven different species of fish could be detected in as little as 25ml of filtered water. One litre replicate samples detected 46 and 43 fish species, with ~70 per cent of the species overlapping between replicates.

Going one step further, while eDNA is used for species detection, environmental cells (eCells) can be used for estimating population abundance. Once the eCells have been sorted into species, further genotyping by sequencing can provide estimates of species abundance. In the future, for example, it may be possible to get a better estimate of the number of Whale Sharks in the world.

Another example from Olly was the novel method for monitoring plant-pollinator interactions. By unravelling the DNA of the pollen taken from insects it is possible to determine which plants are pollinated by which insect—thus saving hours of field observations.

Don Poynton