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. It is called a "theory" because it hasn't been disproven. When it is disproven, it will called a "discarded theory". That's all. I most respectfully suggest that if you do not understand what the word "theory" implies, then you refrain from using it or commenting on it.
Don't you see the contradiction in your statement and how it relates to the rest of your statement?
BTW. It is a nice cartoon.
I take it you have disproved God.
I say something does not exist. Such a statement cannot be proven. But all my opponent needs to do to prove me false is to prove that what I say does not exist, does.
You say your God exists. Okay. Pull him out of you pocket and show him to us.
Oh. You can't.
Hmm...
I suppose you can show me a top quark.
I also believe that you do not understand the word believe.
But the only faith involved in the existence of the top quark is that the grad students and research assistants did their arithmetic correctly, that the physical experiments were performed as stated (hence the need for independent verification and repeatability in laboratory results), and that the mathematical theory has no fatal flaws. All of which is verifiable by a mind of sufficient power.
Okay, so your post proves you don't have God in your pocket. Have you checked your back pocket? He probably wouldn't like being sat on. What about your wallet? Preachers are always checking in their parishioners wallets for something or other. Maybe that's where they keep God? Well, where ever you happen to be keeping Him, pull Him out and let's see Him.
Your's is a much greater leap of faith from any view.
People that have an irrational believe in God should not, never, not once, ever invoke First Causes.
Where'd God come from?
Go ahead. Say He's "eternal", and I can then go find cosmologic theories and hypotheses discussing what the implications of a false vacuum that inflates at a faster rate than it decays on the generation of bubble universes, or in interesting one about how the positive cosmological constant may leading to rending of space-time and the spawning of new universes in an infinite non-convergent series.
And what I'll call up will have some basis in observed fact, unlike religious maunderings.
A study of older North Carolinians published last summer by Koenig and colleagues at Duke and the National Institute for Health (NIH) Research, Rockville, Md., found that weekly synagogue- or churchgoers experienced a 28% lower mortality rate than those attending less regularly. The decline of mortality risk was 35% for women and 17% for men in the study. Participants for this study were interviewed in 1986 about religious attendance, health, health practices, social connections and other variables. Study subjects were drawn from North Carolinians in NIH's national longitudinal database, "Established Populations for the Epidemiologic Study of the Elderly." The sample initially ranged from ages 64 to 101, and 62% were women. The study, "Does Religious Attendance Prolong Survival? A Six-Year Follow-Up Study of 3,968 Older Adults," published in the Journal of Gerontology: Medical Sciences (August 1999), looked at the population sample in 1992, when 30% of participants had died. The report raises important concerns about the striking findings on mortality. The authors believe that future research should examine why frequent attendees of religious services have longer mortality outcomes. Studies should explore the extent to which frequent religious attendance fosters "attitudes of compliance and care for the body that carry over into adherence to medical treatments." For example, they observe, religious congregants are apt to comment on each other's health and encourage one another to see a physician. |
That's why I discuss "theories" and "hypotheses" as opposed the religious fanatics use of the term "fact". I recognize the possibility of error.
You need to prove that a God's little finger is actually doing something. What you posted is not relevant.
So lets here the Conservation of Cosmology theory, which contrary to all the laws and theories known to man, provides an algorithm for an ever expanding universe from nothing.
Cognizant of the fact that some questions cannot be answered so I refuse to invent an invisible man in the sky to comfort myself.
Yet by adhering to an atheistic view you are sure there is no God. An act of faith, no?
Right. The correct answer is "no". I'm waiting for you to prove your absurd claim that your invisible mover exists. Until that happens, my UnGodly Theory stands intact. No faith necessary.
I readily admit my belief in God is a matter of faith.
You, on the other hand, being grounded in science, cosmology et al have an unshakeable faith that such a being never existed. Because you sure the hell don't have the science to prove the question posed above.
From now on you can tell people that you are indeed a man of faith. And mean it.
You can keep yourself entertained all day, I suppose.
I need to prove no such thing. You may not think it is relevant, but somebody did. After all the study was done. And it is evidence of something useful.
Well, let's see Harvey.
And here I thought you could read. Do you have your mother reading the screen to you. She missed the names in post 950 if she is reading the screen to you. It doesn't mention the name Harvey either. But I'm sure you stock up on carrots.
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