Still hope for tropical flies!

Scientists believe some tropical species may be able to evolve and adapt to the effects of climate change. The new findings published in the journal, Proceedings of the Royal Society B, suggests some sensitive rainforest-restricted species may survive climate change and avoid extinction.

But only if the change is not too abrupt and dramatically beyond the conditions that a species currently experiences. Dr Van Heerwaarden and Dr Carla M. Sgrò, from the Faculty of Science extended on an experiment from the 2000s in which tropical flies native to Australian rain forests called Drosophila birchii, were taken out of the damp rainforest and exposed to very dry conditions, mimicking the effects of potential climate change.

In the original experiment the flies died within hours and despite rescuing those that survived longest and allowing them to breed for over 50 generations, the flies were no more resistant, suggesting they didn’t have the evolutionary capacity to survive. Dr Sgrò said this finding suggests there is genetic variation present in these flies, which means they can evolve in response to climate change.

“Tropical species make up the vast majority of the world’s biodiversity and climactic models predict these will be most vulnerable to climate change. However these models do not consider the extent to which evolutionary response may buffer the negative impacts of climate change.”

“Our research indicates that the genes that help flies temporarily survive extreme dryness are not the same as those that help them resist more moderate conditions. The second set of genes are the ones that enable these flies to adapt,” she said. “We have much work to do but this experiment gives us hope that some tropical species have the capacity to survive climate change,” said Dr Sgrò.

Monash University, 29 Jul 2014