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."
It does my conservative heart good to see someone still using the ab urbe condita Roman calendar.
Interesting prediction considering we don't know everything about what neurons do. There are folks who argue that it is the interconnections rather than the neurons that are key. The interconnections change with learning, and we don't have a good model for this process.
Is this part of the argument really important to you? What will become of your argument if, in a dozen years, there are many such patents? Are you staking your position on the bet that this won't happen?
If so can we come back at a later time and and ask you to retract your arguments? And if you aren't willing to stake your position on the lack of patents, why are you making such a big deal out of the fact that no one at FR can point to the patent?
If a frog had a glass ass, it would bust it a hoppin'.
Frankly, arguing against an assertion made in the present with present facts, is not weakened by a hypothetical future. The assertion was essentially, there are lots of "A". I demonstrated that there are apparently no "A"(at least in the U.S.). If one can patent a swinging technique, then I suppose one should be able to patent a kludge no matter how well it functions.
When the per-compononent cost of a circuit approaches zero, any improvement in performance is an improvement.
I think if you look around at the world you will see such things a digital voltmeters at Radio Shack. They replace much simpler analog designs without providing much usable improvement in accuracy or reliability (at least not for the typical Radio Shack customer). This observation could be repeated thousands of times among the everyday objects we live with. Labeling an object with a pejorative name is no more usefull that labeling a person with a pejorative name.
In alle this discussion, you have failed to address the only important point being argued -- that is the the circuits designed by the computer program have features that could that could not be designed by the people who wrote the program.
Are green cats dead or alive?
All cats have the potential of being green, if they are dead long enough...
I want my copy a little less depressed, and a little more employed...
Vacuously true.
Total color blindness is quite rare. Most "color blind" people see a different pallet of colors, where red and green look the same.
the dead know nothing !
Applies to lots of living people I know...
If 10 different people see a car accident there ARE 10 different accounts.
Which has NOTHING whatever to do with Heisenberg's Uncertainty Principle. The ten different accounts of the car accident are NOT the result of not knowing the precise similtaneous momenta and locations of the cars.
Dude, you really need to get out more...
What on Earth are you talking about?
The only thing I have said is that you are incorrect about your use of Heisenberg's Uncertainty Principle, and that you mis-spelled his name.
If that somehow impinges upon your spiritual beliefs, you must have an extraordinarily odd set of beliefs.
Oh come on, you know better. They've got a million nits to pick.
I think we can leave off the conditional portion of that statement.
Kurtzweil does a lot of handwaving on the biology side, but he claims that computers at least should have the capability to exactly simulate the brain.
By the year 2100, everyone will have ported out of their carbon based forms. We will all be converted to software. The creationists will love it.
Certainly! Just adjust a few settings on the Penfield Mood Organ....
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