redOrbit: Tiny creatures at the bottom of the food chain called diatoms suck up nearly a quarter of the atmosphere’s carbon dioxide, yet research by Michigan State University scientists suggests they could become less able to "sequester" that greenhouse gas as the climate warms. The microscopic algae are a major component of plankton living in puddles, lakes and oceans. Zoology professor Elena Litchman, with MSU colleague Christopher Klausmeier and Kohei Yoshiyama of the University of Tokyo, …