Feng Sheng Hu, University of Illinois (image) University of Illinois at Urbana-Champaign Caption University of Illinois plant biology and geology professor Feng Sheng Hu collected core samples from Alaskan lakes. The abundance and diversity of midges buried in sediments offers a reliable record of temperature fluctuations over time. Credit Feng Sheng Hu Usage Restrictions This photo may be used only to accompany articles about the research described in this release. Please credit: Feng Sheng Hu. Disclaimer: AAAS and EurekAlert! are not responsible for the accuracy of news releases posted to EurekAlert! by contributing institutions or for the use of any information through the EurekAlert system.