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."
I could equally argue that one-cells, or unisexuals, or prokariotes, are non-life, because they don't look like us, play bridge, or pay taxes. If life ramped up from basic beginnings in constrained, mildly ordered natural environments akin to Conway's game of Life, then your claims about life-vs-non-life are just spurious word-games. At some point, unlifelike automata turned into lifelike automata. Where that supposed barrier is, differs depending on what criteria for "real" life you have arbitrarily chosen.
You obviously are trying to confuse the issue. You have often argued very strongly for abiogenesis. As to games and other nonsense about life from non-life there are none that can surmount the problems against it that real science has shown.
As to your atheism, I see no difference in your writings from those of atheists. Like you they also hate God.
For one thing, non-life cannot 'evolve'. YOu need a complete living thing to start off the life process and that requires at a minimum some half million DNA pairs. We do know that there is no needful arrangement of these pairs as regarding chemistry. We do not know of any DNA even in non-living things. Besides the arrangement of the DNA problem you have a few others in achieving life from non-life. One is that it takes more than DNA to make a living thing. You need the proteins, and the whole organism for life to work and be able to replicate itself. You thus have a chicken and egg problem here. In addition you have the problem of RNA reading the symbolic DNA code. This is impossible without a designer.
You mean the switch from an interesting discussion to yet another recitation of the exact same feeble,
As usual, when caught playing games the evolutionists insult. You completely twisted my words around from a discussion of evolution to one on abiogenesis to which they did not apply.
What we were discussing was the fitness cost of non-working functions and organs which evolutionists are forced to assume in order to make their theory work.The problem for evolution is to slowly, gradually, in small steps create a totally new organ, function, etc. with each single step making the organism more fit. You do not wish to discuss this since such is impossible and the article completely avoids the question of fitness cost for that very reason.
The problem with turing machines as the source of life from non-life is that only intelligent designers build turing machines. The only intelligent designer possible at the time life began is God.
donh: That is correct.
whattajoke: Let it also be known that I, whattajoke, an avowed non-theist, non believer in anything supernatural at all, cannot disagree with your statement.
quickl: Wow, you've finally gotten what we've been saying all along?
dimensio: I do not, however, see such an assertion as incompatable with or contradictory to the theory of evolution.
So tell me fellas, how is it you can allow for a supernatural creation of the universe and a supernatural beginning of life, but reject with absolute certainty --yet without any proof whatsoever--, a supernatural beginning for man?
Don't tell me it is because special creation is unscientific. You just admitted the possibility of two other "unscientific" events.
Keying on Fully as the evidence that the Church accepts Darwinian evolution? If not, what other evidence do you offer about the Church's acceptance of this as man's origin? I am not aware of any and I have checked extensively since returning to the Church. I am happy to take the info I presented to you from the Cathechism of the Church and writings from different Popes and follow their conclusions as being current Church teachings. What is your evidence that the Church holds to Darwinian evolution?
Hey, isn't that the best of both worlds or are you saying that doesn't work? Did Hitler, Stalin, or Buddha go to your heaven if they accepted your god in the last 2 minutes of their life?
Your incapacity to read the threads you are discussing remains world class. Wolfram has demonstrated that about one in 256 ramdomly chosen, rudimentary discrete fields of discourse that can generate repeating patterns through simple cell relationships, generate turing machines. Get his book and check it out for yourself--he's done nothing you can't reproduce yourself on your computer.
Apprently, you can't read either. Is this some kind of creationist infection that's going around? Nothing in any of what your quoted deponents said suggests that they "reject with absolute certainty" a supernatural beginning for man.
I can't speak for all skeptics, but what I reject is that there is some sort of slapdown contest between what science knows or cares about, and God's place in creation. Science is about material evidence. About immaterial or unavailable evidence, science quite properly stands mute.
Look whose talking.
You have often argued very strongly for abiogenesis.
This is, as usual, incorrect.
I have represented the 12 or so most common suggestions as to how naturalistic abiogenesis could occur. If we are talking about things that might have been possible, lacking any spectacular evidence one or another--which we do-- there is no substantive reason to reject them in favor of non-naturalistic explanations. More specifically, I have argued that that means the creationist claim--yours in particular--that God did it because no other explanation exists, is simply wishful thinking on creationist's part.
As to games and other nonsense about life from non-life there are none that can surmount the problems against it that real science has shown.
This is, of course, blatant nonsense. There is no major body of scientific thought that rejects abiogenic origins, just as there is none that rejects devine intervention.
As to your atheism, I see no difference in your writings from those of atheists. Like you they also hate God.
So athiests hate an entity they don't believe exists, eh? That must be a good trick. Sure they hate God's run-of-the-mill avaricious, self-satisfied, self-seeking, cruel representatives, but they don't hate God nearly enough; but, So what? That doesn't give you a license to rewrite Webster's to suit your arguments. Obviously, I am not an athiest by any rational measure.
As usual, you couldn't track a conversation sealed in a paper bag with you. Evolution obviously did not begin with the story we presently know about. Regardless of how many times you drag out the theory that prokartiotes shazaamed together from junk yard organics one day because they felt like it.
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