I once stumbled upon a paper that analyzed rat eating behaviour. They basically change their food source only rarely, and tend to eat whatever they smell other rats are eating. This behavior has lots of advantages. Since they only switch food source when they have to, they seldom eat something poisonous. Since they switch to food they smell other rats have eaten, it is unlikely that the other food is poisonous because otherwise the other rat would have been dead.
This is an extremely robust behavior, and I am sure it can be used in some form as a swarming algorithm, much like ant colony or particle swarm.