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Digital Life and Evolution
mrivorey writes "Discover Magazine has a story about The Digital Evolution Lab at Michigan State University. Scientists there have created virus-like computer programs that replicate, mutate randomly, and compete with each other... in other words, they evolve. Among such feats as learning to add and compare numbers, these digital life forms also once avoided scientists attempts at "killing" them, by playing dead.
You can download the project yourself from SourceForge." We first mentioned this in early 2003, but it appears to have developed a good deal since then.
Dan Simmons included this idea in his Hyperion book series, where evolving digital life spead into the "infosphere" and became artifically intelligent. Later it tried to exploit the human race and wipe out large portions of it. People who download the project beware!
Philosophy.
Sounds like something my sister would download... ;O
Here's what I do: Bitty Browser & Andromeda
I wonder how long until the first virus based on this code is released?
"So, mmm-hay, as you can see, I've loaded the evolving virus program onto my wife's Windows computer so that she can experience the evolving and GLAVEN and whatnot for herself. Now, let me just power up the machine and you can see the evolving and surviving and the natural selecting and whatnot for yourself. Brace yourselves, gentlemen."
[[Missing Operating System]]
My wife is going to kill me.
Unknown host pong.
How long after I download this will my computer start threatening to kill me?
The offspring of two sexual creatures is a blend of their genetic material, creating a more diverse species able to endure changing conditions better since there are variations which can adapt. Asexual species exchange genetic material far less and are more similar overall, meaning that come next climate change, they could be screwed, whereas the sexual species might have enough diversity to not only adapt, but thrive under the new conditions.
"If we let things terrify us, life will not be worth living."
- Seneca
Why sex? Meiotic recombination! It's all about avoiding that monoculture...
Oh God. That was close...
these digital life forms also once avoided scientists attempts at "killing" them, by playing dead.
Cool! A new excuse... next time someone calls me at 3AM and says one of my programs has died, I'll just tell them it's playing dead and call me in the morning.
Garg
Garg
Alumnus, Xavier's School for Gifted Youngsters
Is the digital creationists, who'll tell us that Computer Science is an atheist lie and all programs are created by the Giant Sky Pixie^H^H^H^H^H^H^H^H^H^H^H^H^H^H^H^H God.
Slashdot: News for Nerds, Stuff that matters only to them
I'd like to see this run as a distributed computing project, as a sort of race to achieve measurable consciousnessness among the organisms.
Art Schools Dietzilla
Both asexual and sexual reproduction offer the benefit of mutation, which is the key to adaptation and evolution. Asexual reproduction offers the addditional benefit of efficiency, but restriccts you to the (benefitial) mutations within your single parent and their ancestors. Sexual reproduction has a penalty for efficiency, but allows your offspring to benefit from the mutations from two separate gene pools. In many cases, with larger life forms, it also offers the additional benefit of more than one parent to care for the offspring and teach them. (the ability to teach is basically a non-genetic form of evolution, and is much more rapid than genetic evolution) The faster you can evolve, the more successful your species is likely to be.
Asexual is "preferred" by microscopic life because even a poorly evolved microbe can still do well if it can reproduce rapidly and efficiently. In the larger kingdoms though, sexual reproduction encourages more rapid evolution, which is key when competing for the more limited resources of the macro world.
I work for the Department of Redundancy Department.
PETDA protesters are currently rushing to surround the offices of Michigan State University and Nintendo.
http://demo.cs.brandeis.edu/golem/
How we know is more important than what we know.
I see your point on one level...but on another... AI is so far from anything you talk about happening, it's not even funny. I remember how dissapointed I was when I took my first AI class in undergrad--everything seemed just like hacks to me. don't worry--that world class chess AI is no closer to figuring out, well anything that doesn't involve a chess game than..I can't even come up with an analogy to illustrate my point :-p
Suffice it to say that AI as it stands today is not intelligent. A chess program can play chess, but that's all it can do. A robot designed to get from point a to point b can do that, maybe well, but it can't play chess--it's not like AI has an IQ that can be transferred to having a conversation or thinking about taking over the world.
Likewise, learning systems have a long ways to go too. My Prof. was not a fan of neural networks, so I could be biased, but even HOLLYWOOD neural networks have a rather limited use.
I would worry about any one of about a trillion things before I would worry about AI taking over the world.
Actually I kind of object to the term AI in general, for reasons above..
I think this built-in inefficiency is to control the population, no?
No.
At no point will evolution favor inefficiency for inefficiency's sake. There is always an ulterior, efficient motive. In the case of sex, it's forced genetic diversity. One possible scenario for its promulgation could have been a cyclical death-scenario for some manner of simple organism (say, a recurring chemical change in a lake due to a hot spring or toxic runoff) wherein the asexual descendants (a.k.a. clones) would be successful and dominate for long periods but die off in vast waves whenever the environment changed drastically and rapidly. Those that developed sex and its subsequent genetic diversity had a greater chance of fostering enough differing offspring that at least some of their descendants made it through the local cataclysm.
Regardless, it's certainly not an inherent "inefficiency".
It would make sense to introduce sex or its analogue to any life-imitating algorithm, as the implications for the evolution of "mix, match and reward" permutations are many, complex and certainly worthy of further analysis.
Viruses replicate by taking over the mechanisms of a host cell. They have no ability to replicate on their own.
What these researches have created are "digital organisms" which are intended to emluate cells. They don't need to invade other systems to replicate, but do it on their own within the runtime enviroment the researches set up.
I seem to be unable to find any source material for this study. I searched for documents coming out of the University of Kalisz from 1997 to date using various keyword approaches and haven't found anything that looks related. Perhaps I'm not choosing my keywords judiciously.
I'm especially interested in tracking down source material on the experiment you describe because of some of the language you're using. In what sense could they "tell" each other information? How did they "try" to figure out the binary format of other processors? And given the results you're describing, why wasn't there any publicity about this event? It seems something likely to make headlines, especially in the kinds of journals I tend to read...
Could you direct me to a link or a reference containing more information about the experiment you are describing, please? It would be greatly appreciated.
What he wants is more important that what I want. What he wants is also more important that what you want.
That was the old thought. For years now, scientists have been doubting that theory. The work with the digital life has shown that, while it confers more genetic variety, it also allows more genetic damage to collect.
Sexually reproducing organisms do not do any better under most simulation conditions.
Recent studies of giardia have shown that this ancient organism has the genes for sexual reproduction. Apparently, sexual reproduction conferred some powerful advantage, given how early it developed in the history of life. But if this is so, why does giardia not actually use sexual reproduction? The genes are there - they have just never been seen to be activated. In all the conditions so far observed, giardia reproduces asexually. If the advantage of sexual reproduction is so great, why did giardia give it up?
Enquiring minds, etc.
This sig seemed like a good idea at the time....
If You have to ask why sex, then you my friend have truly entered into geekdom.
I salute you!
Once you see your kids starting to demonstrate the worst traits of both your mother and your mother-in-law, you'll begin to question whether that's really an advantage.
...the girls all had headaches for generations. As usual, the blokes were left to fend for themselves and had to work something out. In the absence of technology to support paracetamol production, this was all they could do.
</deadpan>
Got time? Spend some of it coding or testing
Slashdot has alot of Athiests and smart, critial thinkers. It is only natural we piss on Creationism, mainly because it is so lacking of science it is the Micheal Jackson of the scientific area.
If you ask "why have sex" then you are merely at the beginning of the path to Geekdom. When you ask "what is sex?", then will you have attained True Geekdom.
While the "digital life" models may be helpful in visualising what's going on in real life, and in devising experiments to test real life with, the digital environment is about as artificial as it gets.
That said, what the models are showing is that sexual reproduction accumulates changes faster, but does not change the quality of what accumulates. The next step will be to tweak the models even further from reality in order to see them accumulate more advantages than handicaps. Otherwise the results are too depressing.
In analogue life (ironic that digital life should be an analogue of analogue life), genuinely advantageous mutations are collectors items - or would be.
Got time? Spend some of it coding or testing
Its generally clear that sexual reproduction has long term benefits that will help a species... genetic exchange allows multiple benefical mutations to recombine into a single organism rather than competing with each other.
But this benefit is only in the *long term*. What would allow sex to be around long enough in the first place to allow this to come into play? Any individual subgroup is likely to be more successful if they don't have to (1) find mates, (2) maintain all of the extra mechanisms to facilitate recombination, or (3) have only half of their population (the males) actually producing offspring.
There are many alternative hypotheses about how sex could get started (and in what situations it would have short-term benefits) and we're trying to explore these one-by-one in Avida.
Charles Ofria
Director, MSU Digital Evolution Lab
An additional benefit with large organisms (or rather, organisms with brains) is that they can also actively play a part in the gene selection process by evaluating potential mates in an intelligent and decidedly non-random way. Usually (but not always) there is some reasonably rational basis for the selection that ties in with suitability to survival (and more importantly rejecting mates that are poorly suited to survival), so we see with many animals that females will choose the strongest males to mate with, and ignore weaker males or those that appear to have defects. Similar thing when males choose females, although other criteria may be used, usually these are linked to child bearing and raising capabilities.
Weaver birds as an example are notoriously picky about choosing males that are good at building nests - obviously important for successful reproduction.
Intelligent organisms are thus active participants in the evolutionary process - they/we guide it. Each species collectively makes these unintended decisions every time an individual chooses a mate about which "direction" they would like the species to go.
Asexual reproduction doesn't provide an organism the opportunity to make intelligent decisions about the genetic material of its offspring.
There is an interesting book on this topic called "The Mating Mind : How sexual choice shaped the evolution of human nature". It's interesting that sometimes a characteristic may be chosen not out of suitability to survival, but purely out of a kind of "cultural" preference that develops. E.g. Orangotans at some point in their past must have decided they like to be that particular shade of orange. We may "culturally" decide that blondes are hot, thereby "guiding" our species towards becoming increasingly blonde (although that is unlikely to happen, it's just an example).
This reminds me of the "Progranisms" project I saw over on the Gentoo Linux forums:
i ght-progranism.html
r anism-neilh.c r anism-neilh-condensed.c
http://forums.gentoo.org/viewtopic-t-255505-highl
http://www.progranism.com/
Basically some guy put together an executable which makes a few (mutated) copies of itself when it runs, then executes those copies after a short delay. The idea is that executables might evolve which show interesting behaviors.
You can download his source code here:
http://www.progranism.com/junk/progranism-2.3.1.c
Because I like doing strange things, I made a variant of the program which mutates the source code and recompiles it (mutating until it gets something compilable), rather than mutating the executable directly:
http://www.its.caltech.edu/~neilh/progranism/prog
http://www.its.caltech.edu/~neilh/progranism/prog
http://www.its.caltech.edu/~neilh/progranism/ (some cleanup and maintenance scripts)
Unfortunately, it's stuck in a pretty steep local minima -- it makes some trivial mutations, but nothing major. One interesting possibility would be to have it search your hard drive for other executables and source files, and try to "mate" with those.
Another scary possibility would be to have viruses/worms with non-trivial evolution capabilities. That'd be a pretty nasty outbreak to try to control.
Finally, a rather neat-looking project is AI.Planet, which is trying to create an 3D evolving ecosystem/world of intelligent "organisms." Framsticks, a 3D life simulation project, is also pretty cool.
More importantly, Sexual reproduction offers something that's fairly lacking in asexual reproduction: Significant genetic exchange
Actually it offers something else: Increased selection speed.
With asexual reproduction, you basically have to wait until nature kills it. A minroly disabiling problem may allow 50 generations of the organism to survive, just barely, before eventually going kaput. Huge waste of resources, no? Sexual reproduction allows the mate to "screen" the organism. With any degree of intelligence at all, the mate can decide that it's not worth mating after all, in advance, because he/she can see the writing on the wall.
Simple definition usually is that if two organisms can't produce viable, fertile offspring then they're of different species.
Even in sexual organisms, this definition of species has some problems. You can easily have organism A that can breed with B, and B can breed with C, but A and C are incompatable. How do your divide up the species lines in this case?
In general, when a new species forms, each organism has to have others it can mate with, or else they would just die out without any offspring. The speciation process is a gradual one, and so, theoretically, there is probably a path you could follow between any two sexual organisms where any pair on the path could theoretically mate.
In Avida, for simplicity, we determine species by testing each orgasnism against the species of its parent. If it can cross-over at most points with the prototype of that species, it is marked as being part of that same species. If it cannot, we create a new species for it where it is the prototype. Not an ideal method, but it works in most cases (and we rarely need to resort to the species concept).
What's fun, is that this even works for asexual organisms. We can force all possible crossovers (in isolation of course -- this never feeds back into the system) to see if they would have any ability to mate if they has been sexual.
Dr. Charles Ofria
Director, MSU Digital Evolution Lab
I guess one nice thing about open source software is that even those who disagree with you can help you. :)
From the article:
When the Avida team published their first results on the evolution of complexity in 2003, they were inundated with e-mails from creationists. Their work hit a nerve in the antievolution movement and hit it hard. A popular claim of creationists is that life shows signs of intelligent design, especially in its complexity. They argue that complex things could never have evolved, because they don't work unless all their parts are in place. But as Adami points out, if creationists were right, then Avida wouldn't be able to produce complex digital organisms. A digital organism may use 19 or more simple routines in order to carry out the equals operation. If you delete any of the routines, it can't do the job. "What we show is that there are irreducibly complex things and they can evolve," says Adami.
The Avida team makes their software freely available on the Internet, and creationists have downloaded it over and over again in hopes of finding a fatal flaw. While they've uncovered a few minor glitches, Ofria says they have yet to find anything serious. "We literally have an army of thousands of unpaid bug testers," he says. "What more could you want?"
If the advantage of sexual reproduction is so great, why did giardia give it up?
Because they're an intestinal parasite and don't need it?
We can consistently see that asexual reproduction is popular among simple life and sexual reproduction is popular among complex life. This post in this thread gives a possible reason why. Is it that unreasonable to suspect that the more complex a lifeform is, the more benefit sexual reproduction confers? And if we are to take this suspicion seriously, then why would it be surprising that computer simulated models-- which by their very essence are simple-- would fail to demonstrate this benefit? And why would it be surprising that an organism that at one time used sexual reproduction would revert to exclusive use of asexual reproduction after settling into a very simple evolutionary niche, as giardia has?
I do not really see anything in your post that contradicts the purported advantages of sexual reproduction.
Irritable, left-wing and possibly humorous bumper stickers and t-shirts
You will notice that there is no place in there for Atheism, since Atheism defaults to selfishness, which in turn implies no troublesome descendents.
Not necessarily. "Selfishness" may lead to altruistic behavior if altruism is rewarding (i.e. activates brain reward systems). Because there are selective benefits to altruism in many circumstances (reciprocal altruism, nepotism) there are likely genes that cause individuals to enjoy being altruistic, quite independently of their religious beliefs.
> Darwinism doesn't explain everything as tidily as some may think.
ID doesn't explain anything at all.
> Behe goes on to say some systems can't be produced by natural selection because "any precursor to an irreducibly complex system that is missing a part is by definition nonfunctional."
His IC argument ignores the possibility of changing the function of a system, which is probably the most common way evolution acts.
> Heavy stuff
I would have said "deep".
ID is nothing but creationist apologetics, bowlderized to try to sneak it past the US court system.
Sheesh, evil *and* a jerk. -- Jade
> Even when we believe they are false, ideas like Creationism threaten to unravel the framework by which we understand the world.
Huh? Does the idea of a flat earth threaten to unravel astronomy and planetology? Does the idea of alchemy threaten to unravel chemisty?
> We feel better if we are able to rationally take apart offending ideas, but, failing that, we will mostly settle for just shouting them down when we are among those who we feel sure will agree one way or the other.
Sorry, but geologists rationally took apart creationism 200 years ago.
> Frankly, 99% of the
Oh, please. Most of their claims are simple logical fallacies and/or attempts to 'refute' science by misrepresenting well known facts or arguing that Darwin was a baby raper.
Sheesh, evil *and* a jerk. -- Jade