ECHO
| Collection | International Encyclopedia of Systems and Cybernetics |
|---|---|
| Year | 2004 |
| Vol. (num.) | 2(1) |
| ID | ◀ 997 ▶ |
| Object type | Discipline oriented, Methodology or model |
- “A simulation of an ecosystem in which digital organisms try to survive and reproduce”.
This model has been created by J.H. HOLLAND.
R. RUTHEN describes it as follows: “All organisms are endowed with ”chromosomes“ that encode offensive and defensive strategies. Each organism wanders through an artificial environment, searching for resources and absorbing them into an internal reservoir. If one organism encounters another, the two fight, and the winner consumes the loser, acquiring all the resources contained in the loser. If an organism obtains enough resources, it produces offsprings whose chromosomes may contain mutations. New species arise with even more elaborate strategies for offense and defense” (1993, p.113).
Initally these simulations did not consider cooperation. HOLLAND, inspired from R. AXELROD Prisoners's Dilemma introduced three modifications:
- “First, each organism can choose to fight for resources or trade for them. Second, each is assigned a tag, which is analogous to a molecular marker on the membrane of a cell. Last, each organism is allowed to develop rules such as ”fight only those organisms that carry a red tag“. If strategies and tags are initially assigned at random, some organisms, by luck, are more inclined than others to use a strategy ressembling tit for tat. Those that play such strategies are more likely to survive and reproduce, thereby perpetuationg the existence of particular tags.”
According to HOLLAND: “What started out as a completely random juxtaposition of tags and strategies begins to develop in a very organized way” and “In the end the digital ecosystem displays both speciation and cooperation — and such deviations as mimicry and lying” (Ibid).
This is again a kind of collective automaton in the making and could probably be used to modelize complex economic and social behavior.