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From: jabowery@netcom.com (Jim Bowery)
Subject: Re: Tierra Working Group Report
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Date: Sun, 14 May 1995 01:16:50 GMT
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charles@regulus.krl.caltech.edu (Charles Ofria) writes:
> Ah, but what if you strip areas of the rain-forest first.  One concern is
> that a hacker will first find a way to wipe out life on the tierra islands
> before sending his own creatures in.  The can be done in a number of clever
> ways, the most obvious of which is just bombarding a soup with so many
> incoming creatures, that all the creatures already there are killed off.

You have just described one of the primary evolutionary methods of
intraspecific competition:  

Differential immunity.

The most widely accepted and obvious cases of this occur when population A
encounters population B and population A carries a pathogen to which it is
immune but to which population B is not immune.

The MHC genes are good evidence that this is a primary evolutionary driver.


I would be surprised if, upon examination, this sort of evolution isn't
quite common in the more sophisticated alife systems.
-- 
The promotion of politics exterminates apolitical genes in the population.
  The promotion of frontiers gives apolitical genes a route to survival.
                 Change the tools and you change the rules.
