Kin selection in bacteria

In a letter to Nature this week, Stuart A. West's group at the University of Edinburgh provides the first empirical data supporting the idea of kin selection in bacteria.

First proposed by W.D. Hamilton in 1964, the theory of kin selection holds that altruistic cooperative behavior preferentially directed at helping a relative is favored because it helps that relative do better and reproduce, which indirectly helps the cooperator to pass on its genes. "This kind of behavior is very well established in social insects—bees, wasps—also cooperative breeding in vertebrates like birds and mammals," West told The Scientist.

The team studied the system of production of siderophores—small molecules that scavenge iron from the environment—in the pathogenic bacterium Pseudomonas aeruginosa. Generating these molecules is costly to producer bacteria (cooperators), but others around it can use the siderophores to their own benefit without paying the price (cheaters).

West's group observed which type of ...