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."
Guess Bill Bennett's a creationist.
Close-- a libertarian den of secularists.
The fox is a relatively modern mammal. Could you provide a reference for this claim?
Interestingly enough, some of the virulent fundamentalist elements of Islam share this belief in Creationism. The Taliban, in particular, was one such group.
Original Airdate: 22-Sep-1979
Plot: Jon and Getraer ride together while Ponch is busy hunting down stars for the annual CHP roller disco. At the pier, a kid observes someone steal a wallet and gets the idea of stealing some change from a woman on a pay phone. He escapes by grabbing onto a bumper of a station wagon. Jon and Getraer find the kid on the freeway and manage to stop the car after the theme. Ponch and Jon go and talk to Mark (the kid's) older sister. Ponch learns that Mark's sister teaches some celebrities how to roller skate so Ponch talks her into getting some for the CHP roller disco. Later, two guys cause an accident when they lower the rear end of their car and create sparks. Following up on the accident, Ponch and Jon visit Jimmy Tyler in the hospital. He's a "big rock star" and Ponch has all his records. Ponch convinces his agent, Frank Balford, to help get some celebrities for the CHP roller disco. Later, the wallet thieves steal a belt pouch. When Ponch and Jon come to the rescue, they get knocked on their backs and the thieves escape on skates. After the briefing, Ponch is near the Beverly Hills Hotel looking at a map to the homes of the stars. A friendly man helps him and announces Jon's arrival with his famous "Heeeere's Johnny!" Ed McMahon drives off as Ponch realizes who he is. Meanwhile, Jimmy gets upset with his agent and fires him. After he goes out driving because he's so upset, Ponch and Jon come across Grossie (who found Jimmy crying on the side of the freeway). Jon lets Jimmy stay at his apartment. Within a minute, Jimmy falls asleep. That afternoon, the roller skating thieves are at it again. They rob a jewelery store as Mark watches. Ponch and Jon each chase the skating men while the woman gets away. As one heads to the beach, we see "To Be Continued"!
Original Airdate: 22-Sep-1979
Plot: Starting with a bit of a re-cap, we continue from where Part I left off. Jon loses the skater he was chasing. Meanwhile, Ponch is still looking for his but can't find him. Luckily Ponch comes up with a plan just before the theme. After riding the carousel, Ponch and Jon ask their roller disco teaching friends to show them the neighborhood. After walking their dates home, Ponch and Jon go to the roller disco rehersal. The next day, Jimmy is managing his hectic life in Jon's apartment with the stereo turned up. Out on the freeway, the anti-tailgaters are still at it and causing accidents. Our heroes find them and chase them. Ponch and Jon make the arrest after the anti-tailgaters back into a telephone pole. Back at Jon's apartment, Jimmy is making lots of noise and making calls to London. Jon has a talk with him while Ponch has a talk with Balford, Jimmy's agent. The next day, the roller skatign thieves rob a bank. Ponch and Jon respond and are helped by Bonnie and Mark, the kid who held onto the car bumper. Bonnie arrests the woman while Ponch arrests the man in the white shirt and Jon and Mark get the guy in the black shirt. Brace yourselves, it's time to Skate with the Stars! It can't be summarized in words. Just when you thought it couldn't get worse, there's the "First-Ever Roller Disco Beauty Contest". That's followed up by a live performance of "Give In" given by Jimmy Tyler. The episode ends with Jimmy and Balford getting back together
HALO jump sans chute?
If there is so much evidence, if the theory has evolved into a fact, if creation is utterly absurd, then why only 50%? Answer: There is a pile of government money, there is coercion in the public schools, there is lying and evidence-manufacturing, there is suppression of opposition and much carnival barking but there is little evidence and there is zero proof.
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