Bacteria that live in the digestive tracts of animals may influence the adaptive trajectories of their hosts.

Clostridium difficile is evolving more robust toxicity, repeatedly attacking its victims, and driving the search for alternative therapies to fight the infection.

By Gayatri Vedantam and Glenn S. Tillotson Wrestling with Recurrent Infections Clostridium difficile is evolving more robust toxicity, repeatedly attacking its victims, and driving the search for alternative therapies to fight the infection. photoillustration by Sean Mccabe; Science Photo Library (boy); Sebastian Kaulitzki/ Istockphoto.com (Intestines); Olena Timashova/Istockphoto.com (Green bacteria); Jiri Flogel/Istockphoto.com (Blue bacteria) As infectiou

Editor's Note: On May 2, the National Academy of Sciences announced the election of 60 new members and 15 foreign associates from nine countries in recognition of their distinguished and continuing achievements in original research. Nearly half of the new members are life scientists. In this article, The Scientist presents photographs of some of the new members and comments from a few of them on their careers and on past and current research. A full directory of NAS members can be found online a

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