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Artificial Life Forms Evolve Basic Memory, Strategy
Calopteryx notes a New Scientist piece on how digital organisms in a computer world called Avida replicate, mutate, and have evolved a rudimentary form of memory. Another example of evolution in a simulation lab is provided by reader Csiko: "An evolutionary algorithm was used to derive a control strategy for simulated robot soccer players. The results are interesting — after a few hundred generations, the robots learn to defend, pass, and score — amazing considering that there was no trainer in the system; the self-organizing differentiated behavior of the players emerged solely out of the evolutionary process."
Wow look at that teamwork.. maybe those guys could represent England?
"amazing considering that there was no trainer in the system;"
Not really, it's merely selecting patterns it is not aware of if it's patterns are "successful" or not. If you run a pattern generator long enough you can get all possible patterns within a finite possibility space.
A bit more than 15 years ago I saw a documentary on Discovery Channel featuring identical work being made by a brittish scientist / computer programmer. His software spawned simple "lifeforms" made up by basic 2D and 3D geometrical objects - cubes, cylinders, flat triangles etc., - that were then trying to evolve methods of how to most efficiently move and travel in the simulated environment they were put in - sometimes an airy environment with ground underneath them, and gravity, and sometimes an "ocean" in which the "lifeforms" swam. Minute after minute the "lifeforms" jiggered and bounced around like broken machinery, but slowly developing a method for moving and navigating that was the most efficient for their particular shape. He spawned caterpillar-like animals made up from chains of cubes, that slowly learned how to wriggle and crawl just like catterpillars and snakes do. He spawned randomized "freaks" that learned that sometimes managed to learn how to walk with their disfiguring, and sometimes learning that the only way was to throw some bodypart around to pull themselves forward. He spawned biped animals that slowly learned how to jump to move forward, an triped animals that learned how to skip from one leg to the other, to the third. He spawned lifeforms in a watery environment that learned how to rhythmically oscillate their bodyparts to create propulsion in order to swim forward and turn around. To me, this was just as impressive, if not more, than the featured story. As a curious detail to it all, the programmer developed his software in BlitzBasic, running on a heavily accelerated Amiga 1200.
In the late 1980s, ecologist Thomas Ray, who is now at the University of Oklahoma in Norman, got wind of Core Wars and saw its potential for studying evolution. He built Tierra, a computerised world populated by self-replicating programs that could make errors as they reproduced.
When the cloned programs filled the memory space available to them, they began overwriting existing copies. Then things changed. The original program was 80 lines long, but after some time Ray saw a 79-line program appear, then a 78-line one. Gradually, to fit more copies in, the programs trimmed their own code, one line at a time. Then one emerged that was 45 lines long. It had eliminated its copy instruction, and replaced it with a shorter piece of code that allowed it to hijack the copying code of a longer program. Digital evolvers had arrived, and a virus was born.
Avida is Tierra's rightful successor. Its environment can be made far more complex, it allows for more flexibility and more analysis, and - crucially - its organisms can't use each other's code. That makes them more life-like than the inhabitants of Tierra.
Actually, organisms using each others code sounds way more like our world than ones that can't leech off each other. They already pointed out viruses, and plenty of species exist today that need other species to continue to survive.. in fact pretty much all animals need to eat other lifeforms because we can't draw energy from the sun directly.
which is totally what she said
The robots need to become spoiled, overpaid millionaires, who refuse to train (France). Brag a lot (England) that their opponent is a bunch of "boys" (Germany), who are afraid of them. Then take a 4-1 shellacking from the "boys." And despite being the defending champions, and having a world class league in their country, bow out early. Because all of the players in their first class league are from South America (Italy), and the they have no good domestic players.
Robots with vuvuzelas? No, thanks. My next nightmare.
Schroedinger's Brexit: The UK is both in and out of the EU at the same time!
I was so amazed by the results claimed for Tierra that I went and reimplemented it myself. And damned if I didn't get similar results. At the time, it blew me away that such a system could come up with novel solutions I hadn't expected or 'programmed in'. Indeed, a couple times it took me a while to even figure out how the things worked.
PHEM - party like it's 1997-2003!
Actually no. The evolution mechanism is really robust.
Basically, if you have a bunch of random individuals, and the 'evolution' just mashes a bunch of the better ones together, you'll see the increase in fitness occurring. But it's not just a small effect : almost any crazy 'mashing together' method works, and the adaptation will spark off unbelievably quickly.
I know this because I did this for my PhD back in 1995. I had a choice then between going the Neural Net path, and playing around with the Genetic Algorithm/Genetic Programming stuff. Simple experiments proved that making NNs 'do the right thing' was a fairly tricky process of getting things set up right (and your formulae had to be right, etc : a fairly sensitive procedure). But the Genetic stuff was amazingly robust : almost any crazy method of crushing individuals together will produce remarkable innovation and learning (on a population basis).
But don't take my word for it, write a small piece of code yourself. The literature makes it sound like a more exact science that it needs to be. As I said, almost any 'mashup' method will work - the 'evolution thing' will simply find a way to 'protect' the important stuff.
So while this looks like 'old news' in some ways, I'm glad that they've got an eye-opening application : More people should know how much the computer guys can add to the biological evolution debate.
I would tag this as "more proof soccer sucks." Really, soccer aficionados claim they see all these advanced movements, and that someone really does play better.
But, let's face it, they don't. They're just a bunch of people running around randomly, and occasionally someone scores by pure chance. That's why the games are always 0-0.
Seeing good soccer in random movement is part of the faith, much like astrologers see divine constellations in the random pattern of stars in the night.
http://www.washingtonpost.com/wp-dyn/content/article/2010/05/28/AR2010052801856.html
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