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."
If that is correct your views are antithetical to theism which necessarilly makes you an anti-theist. No?
Yes, but every society defines "murder" a little definitely. Shooting someone who is stealing your car from your driveway is murder in New York and legal in Texas.
Here is the definition of murder I'm working with, it was included in my post above.
I never mentioned culture, I was talking about theism.
But while we're on culture, there are cultures that still enslave others. Is slavery absolutely wrong morally.
Absurd! Even leaving out the often does not make the statement much more believable.
Did somebody say "Hudson Terraplane?" A fine automobile, yes, but no match for the manificent 1941 Bulgemobile Flamefire
Glad to see you around here tonight, seems like the "save-the-worlders" and the professional worriers have co-opted this site the past few months, nice to see an old face; g'nite.
That is probably due to the fact that you do not know the difference between Uranus and a hole in the ground.
Experience suggests that this is the norm.
"I take my title from the writings of Henry and Brooks Adams. They found American democracy in process of degradation more than a century ago. The decay of the American Presidency from George Washington to Ulysses S. Grant, Henry Adams remarked, refuted altogether Darwin's theory of evolution * * * . To a similar thesis I shall return presently."
"But first, indulge me in some observations concerning the present condition of what is called "democracy" near the close of the 20th century. We are informed by certain voices that soon all the world will be democratic. But whether or not, the American mode of democratic government prevails, the abstract ideology called democratism that any government which has obtained a majority of votes be received as "democratic." Enthusiasts for unrestricted democracy presumably forget that Adolph Hitler, too, was democratically elected and sustained by popular plebiscites. Alexis de Tocqueville warned his contemporaries against ... "democratic despotism," --- 20th century writers discuss "totalist democracy."
... * * ... my additions !
... * * * ... evolutionists are always saying things are getting better when they're actually getting worse !
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