Free Republic
Browse · Search
News/Activism
Topics · Post Article

Skip to comments.

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
Navigation: use the links below to view more comments.
first previous 1-20 ... 701-720721-740741-760 ... 1,961-1,975 next last
To: js1138
Wrong issue. You quoted a technical description of a circuit and asserted it wasn't written by lawyers

Red herring. The issue is whether the human could design a circuit to requirements for other criteria established after the circuit was designed.

721 posted on 05/09/2003 8:56:43 AM PDT by AndrewC
[ Post Reply | Private Reply | To 714 | View Replies]

To: AndrewC
Please provide your evidence for this assertion. I mean the exact performance enhancement across the design stipulations.

As soon as you "prove" a 17 transistor circuit with better performace is significantly worse/bigger/more expensive than a 9 transistor circuit.

722 posted on 05/09/2003 9:00:43 AM PDT by null and void
[ Post Reply | Private Reply | To 716 | View Replies]

To: AndrewC
As an excercise, count the number of transistors in your computer and divide by the cost...
723 posted on 05/09/2003 9:03:01 AM PDT by null and void
[ Post Reply | Private Reply | To 716 | View Replies]

To: AmericanAge
If you take Genesis literally, then you have to believe that the earth is flat, and is covered by a large, clear dome on top of which rests an ocean of water, and that the dome opens up to allow rain to pour onto the earth. Most pictures of earth taked from space dispute this.
724 posted on 05/09/2003 9:03:46 AM PDT by Sofa King (-I am Sofa King- tired of liberal BS!)
[ Post Reply | Private Reply | To 94 | View Replies]

To: AndrewC
I am sorry, but what did you provide me evidence of? Your assertion is that one cannot patent something that one does not understand. Describing what something does isn't the same thing as understanding how it does it.



725 posted on 05/09/2003 9:03:56 AM PDT by CobaltBlue
[ Post Reply | Private Reply | To 691 | View Replies]

To: null and void
As soon as you "prove" a 17 transistor circuit with better performace is significantly worse/bigger/more expensive than a 9 transistor circuit.

Fine, you prove the better performance of the 17 transistor circuit.

726 posted on 05/09/2003 9:04:15 AM PDT by AndrewC
[ Post Reply | Private Reply | To 722 | View Replies]

To: Dataman
Paul who? The Apostle Paul? He didn't write Hebrews!

Hebrews is included among the Pauline epistles. No one really knows who wrote much of the New Testament. OK, replace Paul by 'the unknown author'.

" "Elegchos" is literally "proof" and "ou blepomenon" means "things not being seen with the eyes" like wind and gravity.

I take it you're not a scholar of koine Greek? Fine, neither am I. We're not going to get anywhere by fighting a war of dueling, likely tendentious sources here. Let's stick to the plain English meaning. And in English, a matter that is proven by the preponderance of evidence does not require faith. When yer typical trial lawyer askes a jury to find against Nasty Chemical Company Inc. for turning Erin Brockovich's hair yellow, does he ask them for faith? Not hardly.

A more interesting question might be *why* did the universe create itself?

If the universe were inanimate, the question would be 'how', not 'why'. Stipulating that this has nothing to do with evolution. I think the best answer which is in accordance with modern physical theory would be that the vacuum is unstable with respect to non-vacuum. A vacuum is the most symmetric possible state; but universally in the physical sciences we see phenomena where more symmetric systems spontaneously break symmetry and become less symmetric.

BTW, I'm not likely to be back on FR for about two weeks, so you have the last word.

727 posted on 05/09/2003 9:07:05 AM PDT by Right Wing Professor
[ Post Reply | Private Reply | To 676 | View Replies]

To: AndrewC
As a further excercise, recall why you bought your latest computer. Did the old one quit working???
728 posted on 05/09/2003 9:07:33 AM PDT by null and void (Or was it just that the new one is a little faster, has more memory, or...)
[ Post Reply | Private Reply | To 716 | View Replies]

To: null and void
As a further excercise, recall why you bought your latest computer. Did the old one quit working???

Performance went up and the price went down.

729 posted on 05/09/2003 9:10:41 AM PDT by AndrewC
[ Post Reply | Private Reply | To 728 | View Replies]

To: AndrewC
See the patent:

FIG. 7 illustrates a graph 700 showing experimental results using the cubic function generator 600 as a shaper input to a power amplifier as in FIG. 2. For the experiment, the power amplifier produced an output signal related to the input signal substantially by 1/x.sup.3. The test was conducted using the setup of FIG. 2, with the function generator 220 being replaced by the specific cubic function generator 600. The graph 700 charts the input 210 on the horizontal axis 705 and the output 215 on the vertical axis 710. The cubic function generator 600 causes the output 215 of the power amplifier 205 to be approximately linear, as evidenced by output curve 720.

730 posted on 05/09/2003 9:10:53 AM PDT by null and void
[ Post Reply | Private Reply | To 726 | View Replies]

To: CobaltBlue
Your assertion is that one cannot patent something that one does not understand.

Reread what I "asserted"

I think someone might have difficulty getting a patent for something that they cannot explain the workings, but you never know

I provided evidence of a pretty concise description of a device and how it worked in a patent.

731 posted on 05/09/2003 9:14:29 AM PDT by AndrewC
[ Post Reply | Private Reply | To 725 | View Replies]

To: AndrewC
That was in 2000 AndrewC, you need to pull your head out of your nether regions and think and read on your own.
732 posted on 05/09/2003 9:15:07 AM PDT by Aric2000 (Are you on Grampa Dave's team? I am!! $5 a month is all it takes, come join!!!)
[ Post Reply | Private Reply | To 646 | View Replies]

To: kkindt
Not to poke more holes in the evolutionist's arguements but here's another interesting bit of news.

Typing monkeys don't write Shakespeare

Semper Fi

733 posted on 05/09/2003 9:15:18 AM PDT by dd5339 (Lookout Texas, here we come!)
[ Post Reply | Private Reply | To 715 | View Replies]

To: null and void
Thank you, that is the performance of the 9 transistor circuit. Where is the 17 transistor circuit performance?
734 posted on 05/09/2003 9:16:06 AM PDT by AndrewC
[ Post Reply | Private Reply | To 730 | View Replies]

To: Aric2000
Pull your own head out of your nether regions. That quote was from Feb 2003 Sci Am.
735 posted on 05/09/2003 9:17:39 AM PDT by AndrewC
[ Post Reply | Private Reply | To 732 | View Replies]

To: AndrewC
You skipped an excercise.

Count the transistors in your new machine and divide by the cost.

Hint:
A CPU has over 1,000,000 transistors,
64K of dram memory has ~70,000,
64K of sram has ~ 270,000 transistors,
Add a million or so for "glue" - modems, video cards, math chips, etc.

Lets say you bought a small system ~2,000,000 transistors. And you paid way too much - $2,000.00

That's 0.1¢ per transistor - assuming the monitor, case plastic, wires, circuit boards, assembly and shipping are all free...

736 posted on 05/09/2003 9:22:46 AM PDT by null and void
[ Post Reply | Private Reply | To 729 | View Replies]

To: null and void
You skipped an excercise

Sure, because it is pointless.

P.S. You need an update on your facts.

Each Pentium 4 processor chip has 512K of performance-enhancing level-two cache, 55 million transistors, and advanced (SSE2) multimedia instructions.

737 posted on 05/09/2003 9:27:39 AM PDT by AndrewC
[ Post Reply | Private Reply | To 736 | View Replies]

To: AndrewC
Thank you, that is the performance of the 9 transistor circuit. Where is the 17 transistor circuit performance?

Oops. Right.

The improved performance is asserted in the Feb 2003 Scientific American article. I believe you are familiar with this article since you have been refering to it...

738 posted on 05/09/2003 9:29:23 AM PDT by null and void
[ Post Reply | Private Reply | To 734 | View Replies]

To: AndrewC
I think you just proved my point. The incremental cost of adding a few transistors is negligible.
739 posted on 05/09/2003 9:31:12 AM PDT by null and void
[ Post Reply | Private Reply | To 737 | View Replies]

To: null and void
The improved performance is asserted

Right!! At the moment it is an assertion.

740 posted on 05/09/2003 9:32:05 AM PDT by AndrewC
[ Post Reply | Private Reply | To 738 | View Replies]


Navigation: use the links below to view more comments.
first previous 1-20 ... 701-720721-740741-760 ... 1,961-1,975 next last

Disclaimer: Opinions posted on Free Republic are those of the individual posters and do not necessarily represent the opinion of Free Republic or its management. All materials posted herein are protected by copyright law and the exemption for fair use of copyrighted works.

Free Republic
Browse · Search
News/Activism
Topics · Post Article

FreeRepublic, LLC, PO BOX 9771, FRESNO, CA 93794
FreeRepublic.com is powered by software copyright 2000-2008 John Robinson