Shifting insect populations reveal global warming

An Ohio State University researcher on the international team created a history of changing midge communities for six remote mountain lakes in the Western United States. Midges, resembling mosquitoes but usually don't bite, can live nearly anywhere in the world where there is fresh water.

Over the last 25 years, insect remains showed a dramatic shift in the types of midges inhabiting these lakes, said David Porinchu, the study's lead author and an assistant professor of geography at Ohio State University. The data suggested that warmer-water midges began to push out cooler-water midges in the lake regions studied.

"Climate change has had an overriding influence on the composition of the midge communities within these lakes," he said. "The data suggest that the rate of warming seen in the last two decades is greater than any other time in the previous century.