Posted on 05/08/2003 10:11:06 AM PDT by Nebullis
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."
No they cannot. Reality is too complex to be put into a computer program. Only a fool would think that Sim-City or the Sims are simulations of reality. They are abstractions modeled according to the thinking of the DESIGNERS as to what they wish to prove.
BTW - do you believe that virtual sex can be the same as real sex?
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I did not say it was. This was regarding the issue of abiogenesis and the claim by some atheists here that matter can self assemble and thus create life.
We have seen the mechanism of self-assembly.
Only in living things. And they do not really self assemble anyway. They follow the program set out by the parents. G3K: "The DNA in the simplest organism however, the arrangement of it is not only not due to any natural forces, but it cannot be due to it. Otherwise we would not be able to find all the possible ways in which 3 different bit pairs with 3 possible values (64 in all) appear in the DNA sequences of all species. Such self assembly is totally unknown anywhere in the natural world. For anything even close, one must go and look at humanly designed things."
First, DNA is not an organism.
Seems you need some reading comprehension classes. I did not say that, I said ""The DNA in the simplest organism ". Kindly read what was said before you attempt to refute.
Second, there is no need for anyone to "find all the possible ways" to make a certain sequence to exist in all species. In fact, with evolution you would expect to find common sequences among organisms with common ancestors.
Continuing to discuss what is not being discussed and to create confusion. The post is about abiogenesis. It is pretty clear from the post what it is about. You are attempting to refute something to which the post does not apply.
For bookkeeping purposes, we're still waiting for your definition for what passes as self assembly since you've rejected so many examples.
Actually I made it quite clear in the post you responded to. Inert matter assembling itself together to produce a complex system which is not created by known natural forces. Which indeed could not have been created by known natural forces such as chemical reactions, nucler reactions, wind, etc. This is what had to have happened for DNA to self assemble to create a living thing. Materialists cannot provide an example of anything even a thousand times simpler assembling itself in such a manner. The reason is that matter cannot self-assemble itself in complex ways. Only intelligent designers can assemble matter in ways which have nothing to do with naturally known forces.
No they cannot. Reality is too complex to be put into a computer program. Only a fool would think that Sim-City or the Sims are simulations of reality. They are abstractions modeled according to the thinking of the DESIGNERS as to what they wish to prove.
Do you read your own posts?
For you, in particular, to make this claim takes a lot of gall. Tell us again what the largest possible number is. Tell us again how a circle is not an ellipse.
I asked a question, relevent to a long repetitive main chain of challenges, and insults you've produced here, which you did not answer, busy as you were with other diversions: Since, as you say, life cannot arise from non-life, with what did God form prokariotes?
Yet another law of nature invented at the Gore3000 Academy of Sciences.
The Solar system does not strike you as a regularly constrained, complex assembly of matter displaying marked regularities of behavior? You're not the teesiest bit thrown off of this thesis by the fact that the matter in the universe is mostly confined to a few pinpoints of stars? And you think this compares unfavorably to an acidophilis bacteria in complexity, constrained interactivity and morphological regularity?
This is what had to have happened for DNA to self assemble to create a living thing.
Which is, of course, why no such thing ever likely happened. Something else assembled DNA. As is presently the case--RNA machinery assembles DNA.
Oh, come now, you earned your insults with your continuous rudeness stretched over posts going back almost 2 years. Unlike you, most of the rest of us do not start each new thread with our memories wiped clean of what went before, so that our deponents have to repeat their arguments over and over until they drop out from ennui.
Good grief. How many ways are there to kick a dead horse?
Only a fool would think that trigonometric proofs are simulations of reality. They are abstractions modeled according ot the thinking of the mathematicians as to what they wish to prove.
Yup, I sure do and your semantic nit-picking does not change the fact that you cannot simulate reality, that computer models are abstractions designed to prove what the designer wishes.
Oh, come now, you earned your insults with your continuous rudeness
Aaah defending the slimer by attacking the victim. How Clintonian of you.
Expert's advice?
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Then there are hundreds of thousands engineers and scientists who model everything from chemical processes to hydrogen bombs, buildings to bearings, electronics to automobiles who don't exist in your mind...
Ever hear of ANSYS? SUPREM? Spice?
No? Didn't think so...
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