Two groups of South American and African electric fish, whose lineages diverged 200 million years ago, independently evolved similar ways to generate electricity, according to a new study. In a paper published online this week by the Proceedings of the National Academy of Sciences, researchers report that both groups converted existing sodium channel proteins used for muscle contraction into sodium channels that can generate electricity. Pictured above are Eigenmannia virescens from the Amazon (top) and Brienomyrus vadamans from Africa.