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Artificial Life Experiments Show How Complex Functions Can Evolve
NSF ^ | May 8, 2003 | Staff

Posted on 05/08/2003 10:11:06 AM PDT by Nebullis

Artificial Life Experiments Show How Complex Functions Can Evolve

Arlington, Va.—If the evolution of complex organisms were a road trip, then the simple country drives are what get you there. And sometimes even potholes along the way are important.

An interdisciplinary team of scientists at Michigan State University and the California Institute of Technology, with the help of powerful computers, has used a kind of artificial life, or ALife, to create a road map detailing the evolution of complex organisms, an old problem in biology.

In an article in the May 8 issue of the international journal Nature, Richard Lenski, Charles Ofria, Robert Pennock, and Christoph Adami report that the path to complex organisms is paved with a long series of simple functions, each unremarkable if viewed in isolation. "This project addresses a fundamental criticism of the theory of evolution, how complex functions arise from mutation and natural selection," said Sam Scheiner, program director in the division of environmental biology at the National Science Foundation (NSF), which funded the research through its Biocomplexity in the Environment initiative. "These simulations will help direct research on living systems and will provide understanding of the origins of biocomplexity."

Some mutations that cause damage in the short term ultimately become a positive force in the genetic pedigree of a complex organism. "The little things, they definitely count," said Lenski of Michigan State, the paper's lead author. "Our work allowed us to see how the most complex functions are built up from simpler and simpler functions. We also saw that some mutations looked like bad events when they happened, but turned out to be really important for the evolution of the population over a long period of time."

In the key phrase, "a long period of time," lies the magic of ALife. Lenski teamed up with Adami, a scientist at Caltech's Jet Propulsion Laboratory and Ofria, a Michigan State computer scientist, to further explore ALife.

Pennock, a Michigan State philosopher, joined the team to study an artificial world inside a computer, a world in which computer programs take the place of living organisms. These computer programs go forth and multiply, they mutate and they adapt by natural selection.

The program, called Avida, is an artificial petri dish in which organisms not only reproduce, but also perform mathematical calculations to obtain rewards. Their reward is more computer time that they can use for making copies of themselves. Avida randomly adds mutations to the copies, thus spurring natural selection and evolution. The research team watched how these "bugs" adapted and evolved in different environments inside their artificial world.

Avida is the biologist's race car - a really souped up one. To watch the evolution of most living organisms would require thousands of years – without blinking. The digital bugs evolve at lightening speed, and they leave tracks for scientists to study.

"The cool thing is that we can trace the line of descent," Lenski said. "Out of a big population of organisms you can work back to see the pivotal mutations that really mattered during the evolutionary history of the population. The human mind can't sort through so much data, but we developed a tool to find these pivotal events."

There are no missing links with this technology.

Evolutionary theory sometimes struggles to explain the most complex features of organisms. Lenski uses the human eye as an example. It's obviously used for seeing, and it has all sorts of parts - like a lens that can be focused at different distances - that make it well suited for that use. But how did something so complicated as the eye come to be?

Since Charles Darwin, biologists have concluded that such features must have arisen through lots of intermediates and, moreover, that these intermediate structures may once have served different functions from what we see today. The crystalline proteins that make up the lens of the eye, for example, are related to those that serve enzymatic functions unrelated to vision. So, the theory goes, evolution borrowed an existing protein and used it for a new function.

"Over time," Lenski said, "an old structure could be tweaked here and there to improve it for its new function, and that's a lot easier than inventing something entirely new."

That's where ALife sheds light.

"Darwinian evolution is a process that doesn't specify exactly how the evolving information is coded," says Adami, who leads the Digital Life Laboratory at Caltech. "It affects DNA and computer code in much the same way, which allows us to study evolution in this electronic medium."

Many computer scientists and engineers are now using processes based on principles of genetics and evolution to solve complex problems, design working robots, and more. Ofria says that "we can then apply these concepts when trying to decide how best to solve computational problems."

"Evolutionary design," says Pennock, "can often solve problems better than we can using our own intelligence."


TOPICS: Culture/Society; Miscellaneous; News/Current Events
KEYWORDS: ai; crevolist
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To: general_re
Get an advanced degree in evolution and skip reality -- hard science too !
1,901 posted on 05/24/2003 8:19:49 AM PDT by f.Christian (( apocalypsis, from Gr. apokalypsis, from apokalyptein to uncover, from apo- + kalyptein to cover))
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To: Junior
You forgot "chimps have tails, and there are no plant phyla."

Sigh.... so many blunders; so little time. He is so prolific with his science bloopers that I fear I may never catch up with them all.

1,902 posted on 05/24/2003 9:02:54 AM PDT by longshadow
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To: Junior
No, we insult you because you make stupid statements, Mr. "1720 is a really big number."

I rather think you(in the general, not you in the specific) have a habit of insult. It fairly obvious to even the most recently versed student of exponents that what was intended by 1720 was 10720, a mere twitch of a finger on the keyboard, something quite often seen on these threads. But instead of ignoring it other than stating "I think you meant 10720", you have made it into a cottage industry of insult. You have made stupid mistakes. How often do you see them brought up? When you made them were you insulted?. Or were you corrected?

Yeah, those people that ridicule President Bush on his strateegery look pretty smart right now.

1,903 posted on 05/24/2003 9:05:35 AM PDT by AndrewC (Don't forget the numberpad)
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To: general_re
As I said, his willfull ignorance is utterly breathtaking.
1,904 posted on 05/24/2003 9:10:22 AM PDT by null and void
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To: PatrickHenry; general_re
*****I'm almost afraid to ask what sort of mysticism is proposed as an alternative ... *****

It's already on fllm in the "Handmaid's Tale": http://us.imdb.com/Title?0099731

I remember seeing it in theatrical release; it was mortifying.
1,905 posted on 05/24/2003 9:12:00 AM PDT by longshadow
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To: general_re
I think we ought to collect up the sort of rationally obtained knowledge which is denied here, and preserve it for future generations to rediscover after the end of the coming Second Dark Ages.

They tried that once. It was called the Library at Alexandria.

The "Primitive Deconstructionists" burned it.

1,906 posted on 05/24/2003 9:16:33 AM PDT by longshadow
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To: PatrickHenry
Ever read one of Asimov's best-known stories -- Nightfall? Well worth a look in this context.

Yes. But avoid the movie! It is almost, but not quite, totally unlike the short story.

On second thought, it's the g3k version of the book, an interesting side by side comparison of Asimov's rationality and gk3's ummm, uh...

1,907 posted on 05/24/2003 9:19:40 AM PDT by null and void (...view of reality???)
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To: longshadow
A lot to be said for clay tablets...
1,908 posted on 05/24/2003 9:22:02 AM PDT by null and void
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To: null and void
A lot to be said for clay tablets...

Not if you have to rely on them to take notes in class!

1,909 posted on 05/24/2003 9:25:11 AM PDT by longshadow
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To: AndrewC
It isn't the stupid mistakes. It's the way Holy Warriors--locked as they are in the never-ending struggle against a vast conspiracy of evil, dumb people-- never, never, never eat the crow when it's warm. They never eat it at all. They ignore, or they imagine that they escape under a barrage of distraction. The inability to concede the painfully obvious is the joke, and it's a great one. It's a guy dancing around naked pretending he's got the greatest set of new clothes ever. The whole public pathology has fascinated me for years, but it's starting to get old.
1,910 posted on 05/24/2003 9:28:41 AM PDT by VadeRetro
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To: longshadow
They tried that once. It was called the Library at Alexandria.

The "Primitive Deconstructionists" burned it.

Last Updated:  Sunday, 2 March, 2003, 14:08 GMT
Fire hits Alexandria library
Bibliotheca Alexandrina
The new library opened in October
A fire has broken out in Egypt's newly-opened Alexandria library, and 29 people have been rushed to local hospitals suffering from smoke inhalation.

The fire was blamed on a short circuit.

The extent of damage at Bibliotheca Alexandrina has yet to be determined, but the fire appeared to be restricted to fourth-floor administrative offices.

Sixteen fire engines rushed to the scene and put out the blaze in about 45 minutes. Fifteen ambulances were seen outside the evacuated library.

"We were evacuated to outside, then [the] fire department arrived. The smoke [has] stopped now - everybody is safe, thank God," Leila Dewidar, head of the library's grants division, said.

Student spectators

Fire contributed to the destruction of the original Alexandria library, one of the world's great centres of learning in the ancient world.


1,911 posted on 05/24/2003 9:32:57 AM PDT by AndrewC
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To: VadeRetro
It isn't the stupid mistakes.

I suppose you'll call it distraction when I point out that your statement belies the statement I was replying to.

No, we insult you because you make stupid statements,

1,912 posted on 05/24/2003 9:45:41 AM PDT by AndrewC
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To: VadeRetro
They ignore, or they imagine that they escape under a barrage of distraction. The inability to concede the painfully obvious is the joke, and it's a great one. It's a guy dancing around naked pretending he's got the greatest set of new clothes ever.

What's even more interesting is how the "Holier-than-thou" rush to defend "G3k" when he's being taunted for a mistake he wouldn't even acknowledge for TWO days, but nary a word was heard from them when "G3k" savagely attacked "Junior" for CORRECTLY pointing out Gore's error regarding his claim for "wildly elliptical" planetary orbits. "Gore" had the audacity to slime "Junior" by saying "You don't know beans about Astronomy." Where were the "self-appointed defenders of propriety, decorum, and civility" while this was happening? Where are they now? MIA, I guess, ....... except when they feel like defending the indefensible.

1,913 posted on 05/24/2003 9:54:39 AM PDT by longshadow
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To: longshadow
Junior" for CORRECTLY pointing out Gore's error regarding his claim for "wildly elliptical"

Let me see, how many times on this thread has Gore3000 attacked Junior for this "offense". How many times in the last 3 months has Gore3000 attacked Junior for this "offense". Count the times and the different individuals that have resorted to ridicule.

Why don't you go and ridicule Cancerweb for this definition?

phylum

<biology> The second highest taxonomic classification for the kingdom Animalia (animals), between kingdom level and class level.

(07 May 1998)

1,914 posted on 05/24/2003 10:05:41 AM PDT by AndrewC
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To: AndrewC
How do you explain his other howlers (wildly-elliptical orbits, chimps have tails, there are no plant phyla, a circle is not an ellipse, etc.)? If it had been just one gaffe, he could walk away unscathed and chalk it up to a typo. However, he has a history of such gaffes, and he compounds his errors by attempting to defend them, even going so far as to claim others are making it all up (and then we have to post all those posts again to show him up).
1,915 posted on 05/24/2003 10:17:46 AM PDT by Junior (Computers make very fast, very accurate mistakes.)
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To: Junior
The sun is powered by fission1, a chemical2 reaction, and "phylum" refers only to animals3. Placemarker.
1,916 posted on 05/24/2003 10:39:45 AM PDT by PatrickHenry (Felix, qui potuit rerum cognoscere causas.)
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To: PatrickHenry
Evolution ... cannibalized science and collapsed minds --- thought rot (( germs // virus )) !

Main Entry: can·ni·bal
Pronunciation: 'ka-n&-b&l
Function: noun
Etymology: New Latin Canibalis Carib, from Spanish Caníbal, from Taino Caniba, of Cariban origin; akin to Carib kari< glottalstop >na Carib, person
Date: 1553
: one that eats the flesh of its own kind
1,917 posted on 05/24/2003 12:17:22 PM PDT by f.Christian (( apocalypsis, from Gr. apokalypsis, from apokalyptein to uncover, from apo- + kalyptein to cover))
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To: Junior
If it had been just one gaffe, he could walk away unscathed and chalk it up to a typo.

Gaffes are the rule not the exception on these threads. And Gore3000 is not the only one that may be wrong and not admit it. Long ago someone attempted to draw me into an argument when they thought Gore3000 was wrong. I refused to comply and maintained my distance for some time until it became apparent that insult and derision were not going to abate. I then looked up a source with a position on the question and provided citations and a link. This source agreed with Gore3000. In that thread the argument ceased but the other side did not admit anything. Later in a different thread, I recall, the same argument against Gore3000 was brought up. BTW the source was Talk-origins.

That is one point, but the more relevant point is that "looking someone in the eye" and stating something derogatory is much more acceptable than constant "gossiping and sniping" with the same statements.

1,918 posted on 05/24/2003 1:12:55 PM PDT by AndrewC (mote and beam)
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To: AndrewC
Yep!

Square circle – faith without reason – criticize others for their beliefs and refuse to share your own…

Placemarker Placemarker and Spam Spam…

Happy Memorial Day Weekend!

1,919 posted on 05/24/2003 4:29:37 PM PDT by Heartlander (And thanks for the memories…)
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To: AndrewC
Gaffes are the rule not the exception on these threads. And Gore3000 is not the only one that may be wrong and not admit it.

I disagree with your premise, spelling errors aside. And the evos are positively eager to admit their mistakes and correct them compared to the average Young-Earth-Creationist.

But, back to the point, has the AntiPope excommunicator *EVER* admitted to a making any of these mistake? EVER? Or corrected them in subsequent posts?

Well, allow me to point put that since the answer is a big, fat *NO*, he's no better than a worthless piece of dog poop on these threads in that he engages, not in a discussion or a debate, but a unending and laughable repitition of the same old diatribe, again and again. In fact, he is a laughingstock, as the other posters have pointed out. Don't you think the YEC's (or the ID/IOT's that you sometimes count yourself among) would be better off without having to defend his ludicrous posts?

And, more to the point, why do you waste your time defending the indefensible? What does it gain you to defend such a laughingstock? Do you think it raises the tide on your side and floats your boat? Come on, spill it for all of us to see and evaluate.

1,920 posted on 05/24/2003 4:32:32 PM PDT by balrog666 (When in doubt, tell the truth. - Mark Twain)
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