In the experiment, published this week in Nature Nanotechnology, the researchers slathered one side of a sheet of rubber with the bacterial spores. When the sheet dried it curled up, much like a leaf does after it falls from a tree. Increasing the humidity caused the sheet to straighten out again. Researcher Ozgur Sahin then built a humidity driven generator out of Legos, in which the spore-coated rubber acts as a cantilever that flips back and forth, driving a rotating magnet to produce electricity.
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