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From: sa209@utb.shv.hb.se (Claes Andersson)
Subject: Re: It's ALIVE!!!
Message-ID: <1995Feb1.190506.14405@gdunix.gd.chalmers.se>
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Date: Thu, 2 Feb 1995 01:23:16 GMT
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keithw@wam.umd.edu (Keith) wrote:
>Well, not quite, but I'm close.  I've got myself a little world right
>now.  In this world are randomly distributed debri of the type rock or
>food.  Placed into my world are any number of bugs I desire.  At the
>moment they adhere to rules I have designated:
>Level 1 priority: if they're on top of food, they spend that round
>eating it.
>Level 2 priority: don't walk over a rock or another bug and do not walk
>into a square where a bug may walk.  (does he see another bug facing
>the same square he's facing?)
>Level 3 priority: B-Line for the closest food source he can see (note
>his vision is limited.  See below.
>Level 4 priority: Wander aimlessly if no food is in sight.
>
>With these rules they don't bump into one another and don't go over
>obstacles such as rock and make the shortest path to the closest food.
>They can see a ninety-degree angle as follows:  he can see any cell
>with an X.  He is located at B (for bug :) which he can also see to
>check if he should eat food this turn:
>
>facing north:       facing north-east:
>X X X X X X X       X X X X
>  X X X X X         X X X X
>    X X X           X X X X
>      B             B X X X
>
>etc. etc. etc.  He cannot see past a rock however.  They block his view
>so he can't be aware of food on the opposite side.  Kinda neat huh.
>
>My problem is this and I invite any all comment please:
>This world has no evolution or learning yet.  I'm going to impliment
>genes into the bugs.  I have already assigned an energy variable to the
>bug that depletes as he moves and increases when he eats.  If he dies
>he turns into a plant (fertilizer).  I could take the death becomes
>plany thing out easily enough.  It doesn't really matter.  I said plant
>because that's the food source now, but you could think of it as
>becoming an edible corpse because that's the point I was making with
>it.  By becoming a plant, another bug can eat them, once, as with any
>other plant.
>So, I want genes, reproduction (asexual, cross-over/sexual, whatever),
>possibly mapping skills, short term memory, not long term memory
>(unless of course that figures into behavioral genes which could be
>seen as long term memory but it's more inherited, like ducklings being
>afraid of Hawk sillouettes in the sky.  It's not long term memory, but
>it's permanant.
>I really can't nail down what my genes need to be.
>Attraction/Detraction to various things (rocks, food, other bugs),
>energy requirements, speed, I dunno.  It seems so one-sided.  If have a
>speed gene, it can only be naturally selected one way.  Slow bugs need
>to have some environmental advantage so that it can sway either way,
>possibly less energy requirement.  Any ideas would be much appreciated.
>

 I made a simillar program for my B. sc. thesis where robots evolved
a strategy for getting from point A to point B in a random maze. If you
are interested in reading the paper, just mail me and I'll send it.

 To put it short: Assume from the start that the bugs are stupid, I mean
really stupid, they don't even know that it is good  to eat food and they
don't know that it's good to proceed forward if they are closing in on
the target.

 If the system isn't too complex, you can start with random generation
else mutations of a number of constructed strategies will have to do. I
gave my robots a number of perceptions and a number of reactions
for example:

PERCEPTIONS
Closing in on target : BOOLEAN
Target to the right   : BOOLEAN
Standing still           : BOOLEAN
..
