Vinegar flies behind the times

Drosophila, the vinegar fly, gives us clues about climate change, reports Geoff Maslen.

The insects are released in an area where there is no food resource other than a bucket of rotting banana mush. The students capture the flies with nets, put them in tubes and return to the laboratory where they are go under UV light and are separated.

Professor Hoffmann says that on a hot day the flies can travel up to 150 metres but in cold weather they move only a few metres from their release point. But what does all this effort prove?

“One way animals can counter the effects of climatic extremes is via physiological acclimation,” Professor Hoffmann says.

But acclimating to one extreme decreases their ability to survive under different conditions. If temperatures fluctuate, organisms acclimated to cold or hot conditions can suffer a decrease in fitness as temperatures move to the middle or the opposite extreme.

If you look at some of these specialist species that are very restricted in their distribution they don’t seem to have the adaptive potential, Professor Hoffmann says.

“As climate change comes in, those species will have lot more difficulty coping.”

The Age (Autralia), 25 Feb 2008