Insect 'soup' serving up rapid biodiversity monitoring

(Press-News.org) Griffith University researchers have taken part in an international study which has discovered a fast but accurate means of identifying changes to the biodiversity of a region.

And the secret lies in crushed up insect "soup".

Traditionally, many thousands of hours have been spent by researchers gathering, classifying and recording insects and animals in order to understand the natural ecology of a region. Any changes to the biodiversity of that area could then be determined only by more labour-intensive collecting and recording.

Research published today in the journal Ecology Letters, however, shows that a process known as 'metabarcoding' is much faster and yet still as reliable as standard biodiversity datasets assembled with traditional labour-intensive methods.

Griffith University's Professor Roger Kitching, Dr Louise Ashton, and Dr Aki Nakamura took part in the study, along with scientists from UK, China, and Malaysia.

Chair of Ecology in Griffith's School of Environment, Professor Kitching said the breakthrough means that changing environments and endangered species can be monitored more easily than ever before.

"Every living organism contains DNA, and even small fragments of that DNA can be used to identify species," Professor Kitching said.

"Each soup combines hundreds to thousands of insects caught using insect traps, but this poses no threat to endangered species because the numbers captured still amount to only a tiny fraction of their overall populations. We can then extract the DNA of all those insects from the 'soup'."

Because the process uses sequencers that are relatively cheap, the process can be repeated often, say weekly or monthly.

"If the environment changes for the better or for the worse, we will know about it because the mix of DNA present in the "'insect soup"' will also change," Professor Kitching said.

"Thereby we have a rapid, sensitive and inexpensive warning system if the state of nature in that place changes.'

Professor Kitching said that while the cutting-edge molecular technology "metabarcoding" would never entirely replace the more time-consuming specimen-based approaches, it was reliable.

"We compared our results with high-quality datasets collected in Malaysia, China and the UK which combined more than 55,000 arthropod and bird specimens and took experts 2,505 hours to identify," he said.

"We found that our 'soup' samples give us the same biodiversity information as those gold-standard datasets."

'Metabarcoding' is already being used to reliably inform policy and environmental management decisions.

In one instance, the World Wildlife Foundation and Copenhagen University have applied Metabarcoding to bloodsucking leeches as a means of monitoring endangered mammals in Vietnamese and Laotian rainforests.

By creating a 'leech soup' it was possible to build a list of mammals in the area and know more about whether park conservation is working.

### The research was funded by the Natural Environment Research Council UK, the Chinese Academy of Sciences, the Queensland Government, the National Science Foundation of China, and the Yunnan provincial government.

'Reliable, verifiable, and efficient monitoring of biodiversity via metabarcoding' has been published in the journal Ecology Letters.