Article: Kin selection in bacteria

From: Robert Karl Stonjek (rstonjek_at_bigpond.net.au)
Date: 08/27/04 

Date: Fri, 27 Aug 2004 15:45:04 +0000 (UTC)

Kin selection in bacteria
Study of siderophore production confirms theory in Pseudomonas
By Cathy Holding

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 behavior was favored under different
conditions, exploiting a serendipitous color difference between producers
and nonproducers of siderophores. "What we observed is that when relatedness
is high, the cooperators spread to fixation and take over; and when
relatedness is low, the cheaters spread to take over," West said, meaning
that higher relatedness had a tendency to favor selection for more altruism
or cooperation-and confirming Hamilton's theory.

Read the rest at The Scientist.com
http://www.biomedcentral.com/news/20040826/01

Posted by
Robert Karl Stonjek