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Cover image: Epulopiscium sp., symbionts of surgeonfish, are gigantic bacteria that can grow to be >600 μm long. They contain thousands of times as much DNA as Escherichia coli, but the nature of Epulopiscium DNA has been a mystery. Mendell et al. find that Epulopiscium DNA consists of tens of thousands of copies of its genome, which may enable the bacteria to escape the growth limitations imposed by diffusion. See the article on pages 6730–6734. Image courtesy of Esther R. Angert.