Climate change has dramatically altered the genetic makeup of vinegar flies along Australia’s east coast over 20 years, Monash University researchers have found.

It’s the first time climate change has been shown to cause such a rapid change to a species’ genetic composition.

The discovery, by researchers from the Centre for Environmental Stress and Adaptation Research in Monash’s School of Biological Sciences, means vinegar flies could help alert scientists to climate change, and the possible extinction of species less able to adapt to a rapidly changing environment.

Vinegar flies have a short life cycle, are closely associated with human habitation, and quickly become adapted to their environment such that strains from cool temperate climates are substantially genetically different to strains from tropical regions.

Dr Paul Umina and Associate Professor Stephen McKechnie, in collaboration with Professor Ary Hoffmann from La Trobe University and Ms Alisha Anderson, looked at several genetic ‘markers’ in the vinegar fly that are known to respond to temperature and other environmental variables.

“The markers show variation, first described 20 years ago, that is directly associated with latitude such that if it is known at what latitude the fly was sampled, the frequency of the genetic marker in that population can be predicted,” Dr McKechnie said.

Because climates are changing, the research team re-examined the genetic markers in flies from far north Queensland to Tasmania to see whether the frequencies of the markers in the fly populations had changed since they were first measured.

Their research has been published today in the international journal Science.

“We found that the present day genetic constitution of the species around, say, Sydney is now the same as it was 20 years ago further north in Coffs Harbour. All the fly populations are now genetically equivalent to what they previously were roughly 400 kilometres north.” Dr McKechnie said.

“The flies are adapting as the climate along the eastern coast of Australia is gradually becoming warmer and drier. Mean temperature is increasing at most coastal locations at a rate of 0.1 to 0.3 degrees every 10 years, while rainfall is decreasing at a rate of 10-70mm per year,” he said.

Many species, such as those with long life cycles, can’t adapt to climatic changes as quickly as the vinegar fly, but Dr McKechnie believes the genetic markers of this species, which are so closely associated with climate, could be used to detect climate change early. “This could act as an early warning system so that something could be done locally to combat the threat of extinction for species that can’t adapt quickly, improving their chance of survival.”

Original press release: Humble Fly a Predictor of Climate Change (Monash University)