Weapon-wielding marine microbes may protect populations from foes
Professor Martin Polz, left, and postdoc Otto Cordero examine a petri dish of Vibrio bacteria.Photo: James M. Long, MIT Competition is a strong driving force of evolution for organisms of all sizes: Those individuals best equipped to obtain resources adapt and reproduce, while others may fall by the wayside. Many organisms — mammals, birds and insects, for instance — also form cooperative social structures that allow resources to be defended and shared within a population. But surprisingly, even microbes, which are thought to thrive only when able to win the battle for resources against those nearest to them, have a somewhat sophisticated social structure that relies on cooperation, according to MIT scientists. These researchers have recently found evidence that some ocean microbes wield chemical weapons that are harmless to close relatives within their own population, but deadly to outsiders. The weapons are natural antibiotics produced by a few individuals whose...