Artificial Life Experiments Show How Complex Functions Can Evolve

NSF ^ | May 8, 2003 | Staff

[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."

[CobaltBlue]

>>I don't think I'd like to hear what you think a Christian is.<<

A true Christian is someone who follows the teachings of Christ.

Love your neighbor as yourself, turn the other cheek, do unto others as you would have others do unto you, if someone asks for your coat give him your cloak too, heal the sick, comfort the afflicted, walk the extra mile, blessed are the meek. Stuff like that.

[js1138]

All things dull and ugly,
All creatures short and squat,
All things rude and nasty,
The Lord God made the lot.
Each little snake that poisons,
Each little wasp that stings,
He made their brutish venom,
He made their horrid wings.
All things sick and cancerous,
All evil great and small,
All things foul and dangerous,
The Lord God made them all.
Each nasty little hornet,
Each beastly little squid,
Who made the spikey urchin,
Who made the sharks, He did.
All things scabbed and ulcerous,
All pox both great and small,
Putrid, foul and gangrenous,
The Lord God made them all.
AMEN.
Monty Python

[js1138]

http://www.sciam.com/article.cfm?colID=1&articleID=00073FCE-F36F-1E19-8B3B809EC588EEDF

[Aric2000]

LOL, OMG, ROFLMAO!!!

Gotta love your posts, just gotta!!

[Aric2000]

Thank you for finding that, I have been frantically searching for the last 30 minutes or so.

Hah, now I can beat on AA some more.

Thank you.

[Dimensio]

The miracle of matter creating itself.

How does evolution assume this?

The miracle that before (!) time there was no time.

How do evolutionists assume this?

The miracle of an infinitely small compression of all matter.

How do evolutionists assume this?

The miracle that time began.

How do evolutionists assume this?

The miracle of nothing exploding!
The miracle of an infinitely high temperature at the beginning of the universe.
The miracle that quarks and photons gave birth to the table of elements.
The miracle that particles departing from each other at (or above) the speed of light formed planets and stars.
The miracle of life creating itself!
The miracle that rocks gave rise to intelligence!

How do evolutionists assume any of this?

The miracle of one-celled animals granting themselves an entire library of genetic info.

I don't know of any evolutionists who assume this.



The miracle of billions of transitions leaving no transitional fossils.

I know that most evolutionists don't assume this, given the documentation of many transitionals.

The miracle of frogs turning into princes.

I don't know of any evolutionists who assume this, unless you're oversimplifying something.

The miracle of a pig's tooth evolving into a man, his family and an entire village.

I assume that you are referring to a hoax that was eventually unmasked? Tell me, was it unmasked by creation scientists?

[CobaltBlue]

>>What Christianity teach on how to deal with nonbelievers?<<

If I recall correctly, Christ said, he who has ears, let him hear.

Paul said "Let your conversation be always full of grace, seasoned with salt, so that you may know how to answer everyone" Colossians 4:5-6 (had to look that up).

[Aric2000]

Nice one Cobalt, very nice.

[AmericanAge]

And you leave out the part about spreading his word. Figures.

[CobaltBlue]

Thank you. Good reason to subscribe. For the kids we get a lot of magazines including Discover and National Geographic but not Scientific American.

[AmericanAge]

That just means that their fossils haven't been found elsewhere - probably buried under a huge amount of flood debris. Of course there's tons in Australia - that's where they're currently living. :)

[Dimensio]

It didn't 'adapt' because any mutations that would have enabled it to attack the normally-resistent bacteria were either never came about or did not provide an advantage for reproduction that would allow such a strain of penicillin to thrive and overtake the old one.

[js1138]

Unfortunately you have to be a subscriber. I think I will try to scan the article and freepmail the text, but it might be tomorrow.

[f.Christian]

"Stuff like that" ... 'sheoples' --- for the ravening wolves -- slaughter !

[CobaltBlue]

>>Figures.<<

Now, now, where is the gentility in that? Seems rather hostile to me.

"Love your enemies and pray for those who persecute you." Matthew 5:44.

[AmericanAge]

You are not my enemy; just a person I am debating with for the purpose of spreading His word.

[AmericanAge]

"It didn't 'adapt' because any mutations that would have enabled it to attack the normally-resistent bacteria were either never came about or did not provide an advantage for reproduction that would allow such a strain of penicillin to thrive and overtake the old one."

So, if these things evolve, though, why didn't this one? Again, evolution rests on the concepts that if it doesn't evolve, it perishes. So, if they put it in an environment where it was competeing with the bacteria that infect us, it would die off, would it not? Especially given the evolutionist's magic wand of "time"?

The only reason could be that it didn't have an advantage. But we started with the premise that the reason Pennicillium hurt bacteria to begin with was that it gave it an advantage.

All we're left to conclude is that they're not evolving.

[js1138]

The best magazine in the world for people over age 12 is Science News. It's the only subscription of any Kind I pay for, although I have received a number of magazines as gifts.

http://www.sciencenews.org/

[CobaltBlue]

I appreciate that, but I don't think calling me an atheist is very Christian.