Posted on 06/17/2002 4:40:34 PM PDT by Nebullis
CHAMPAIGN, Ill. — Life did not begin with one primordial cell. Instead, there were initially at least three simple types of loosely constructed cellular organizations. They swam in a pool of genes, evolving in a communal way that aided one another in bootstrapping into the three distinct types of cells by sharing their evolutionary inventions.
The driving force in evolving cellular life on Earth, says Carl Woese, a microbiologist at the University of Illinois at Urbana-Champaign, has been horizontal gene transfer, in which the acquisition of alien cellular components, including genes and proteins, work to promote the evolution of recipient cellular entities.
Woese presents his theory of cellular evolution, which challenges long-held traditions and beliefs of biologists, in the June 18 issue of the Proceedings of the National Academy of Sciences.
Cellular evolution, he argues, began in a communal environment in which the loosely organized cells took shape through extensive horizontal gene transfer. Such a transfer previously had been recognized as having a minor role in evolution, but the arrival of microbial genomics, Woese says, is shedding a more accurate light. Horizontal gene transfer, he argues, has the capacity to rework entire genomes. With simple primitive entities this process can "completely erase an organismal genealogical trace."
His theory challenges the longstanding Darwinian assumption known as the Doctrine of Common Descent – that all life on Earth has descended from one original primordial form.
"We cannot expect to explain cellular evolution if we stay locked in the classical Darwinian mode of thinking," Woese said. "The time has come for biology to go beyond the Doctrine of Common Descent."
"Neither it nor any variation of it can capture the tenor, the dynamic, the essence of the evolutionary process that spawned cellular organization," Woese wrote in his paper.
Going against traditional thinking is not new to Woese, a recipient of the National Medal of Science (2000), and holder of the Stanley O. Ikenberry Endowed Chair at Illinois.
In the late 1970s Woese identified the Archaea, a group of microorganisms that thrive primarily in extremely harsh environments, as a separate life form from the planet’s two long-accepted lines – the typical bacteria and the eukaryotes (creatures like animals, plants, fungi and certain unicellular organisms, whose cells have a visible nucleus). His discovery eventually led to a revision of biology books around the world.
The three primary divisions of life now comprise the familiar bacteria and eukaryotes, along with the Archaea. Woese argues that these three life forms evolved separately but exchanged genes, which he refers to as inventions, along the way. He rejects the widely held notion that endosymbiosis (which led to chloroplasts and mitochondria) was the driving force in the evolution of the eukaryotic cell itself or that it was a determining factor in cellular evolution, because that approach assumes a beginning with fully evolved cells.
His theory follows years of analysis of the Archaea and a comparison with bacterial and eukaryote cell lines.
"The individual cell designs that evolved in this way are nevertheless fundamentally distinct, because the initial conditions in each case are somewhat different," Woese wrote in his introduction. "As a cell design becomes more complex and interconnected a critical point is reached where a more integrated cellular organization emerges, and vertically generated novelty can and does assume greater importance."
Woese calls this critical point in a cell’s evolutionary course the Darwinian Threshold, a time when a genealogical trail, or the origin of a species, begins. From this point forward, only relatively minor changes can occur in the evolution of the organization of a given type of cell.
To understand cellular evolution, one must go back beyond the Darwinian Threshold, Woese said.
His argument is built around evidence "from the three main cellular information processing systems" – translation, transcription and replication – and he suggests that cellular evolution progressed in that order, with translation leading the way.
The pivotal development in the evolution of modern protein-based cells, Woese said, was the invention of symbolic representation on the molecular level – that is, the capacity to "translate" nucleic acid sequence into amino acid sequence.
Human language is another example of the evolutionary potential of symbolic representation, he argues. "It has set Homo sapiens entirely apart from its (otherwise very close) primitive relatives, and it is bringing forth a new level of biological organization," Woese wrote.
The advent of translation, he said, caused various archaic nucleic-based entities to begin changing into proteinaceous ones, emerging as forerunners of modern cells as genes and other individual components were exchanged among them. The three modern types of cellular organization represent a mosaic of relationships: In some ways one pair of them will appear highly similar; in others a different pair will.
This, Woese said, is exactly what would be expected had they individually begun as distinct entities, but during their subsequent evolutions they had engaged in genetic cross-talk – they had indulged in a commerce of genes.
I make no such argument nor anything remotely like it, so I am going to ignore the rest of this response. For ought I know, God's abundant miracles direct every little sperm to its destined egg. But science restricts its attention to material things for which there is material evidence to chew on. I have no significant opinion I care to share about whether God is the source of All We See. He could well be, but that doesn't affect what science needs to concern itself with.
Ok. For the sake of argument, let's say this new wrinkle is true, and the previous theories are wrong.
Assuming this new wrinkle is true, and the Darwinism we have all been force-fed and brainwshed in school which has been mandated, is, indeed, wrong... then, doesn't that mean that what we have been inculcated with HAS BEEN A LIE?
In which case, given the extreme arrogance with which that (now, according to THIS ARTICLE) incorrect theory was forced down our children's throats, then why should we believe the NEXT theory the scientific community comes up with? (and after THAT theory falls, the next and the next?)
What if it turns out the Bible is right? Then the prejudiced mandating of "evolution" in our schools will prove to have been perhaps the most monstrous act of coercion in American history, no?
But okay, let's assume a previously believed scientific theory is wrong. So what? Einstein's theory of relativity changed everything. Evil Plot or the advance of science? Plate Tectonics overthrew a lot of perfectly good theory. Evil Plot, or because it explained the known facts better?
When we get more facts, and they don't fit into what we believe now, do you think we should ignore so we can stick to the old theory?
It's not just science, by the way. It happens all the time in science and in technology, too. There were a lot of very unhappy electrical engineers along about the time gates got introduced. Seems a lot of what they knew suddenly became "history" not "electrical engineering."
If you want to use the Bible in science class, why stop there? Why not for American history, navigation, and fashion tips?
Actually there are fashion commands in the Bible. It orders us not to wear clothes of mixed threads.
What if it turns out Paganism is right?
We can't teach every nutball theory on the off chance it might be right. What we do, what every person has to do in their lives, is go with best evidence. Evolution is the best fit to the material evidence. It hasn't been seriously challenged. It is still king of the hill.
They rammed DARWINISM down our throats, didn't they?
Could there be any doubt?
Actually, they did -- of course I went to a Catholic school -- but that's what they taught -- Darwinian evolution. I learned not to give any lip back to the nuns or priests teaching the class. In those days they'd give you a good whack.
Regardless, science is supposedly concerned with the truth. If organisms were designed, then evolution is false. If the DNA code is like a computer program, it is clearly designed and could not have evolved.
Then we should not be teaching evolution. It is totally nuts and it has been disproven by every single major discovery in biology of the last 150 years.
It may make fetching easier, but it takes time to pack it. Situation here is different. We have genes who have to be replicated exactly, that is why a lot of double checking is needed. We also have a program, and programs are never packed when being used. You also have to realize that we are just beginning to learn the many things DNA does. Keep watching and you will see how amazing it is the way it does things.
We sometimes call this argument the Great Buzzsaw of subjectivity. The key is exactly the strength of the evidence. That is what science works on full time: the strength of the evidence. Proposing that because there is an element of unavoidably subjective evaluation of the strength of any given set of evidence does suddenly throw the election into default. We like naturalistic evolutionary explanations because of their track record so far, and the failure of creationists or IDers to provide a definitive countervailing example. The instant you guys come up with something definitive, it will become part of science--just taking potshots at our feeble attempts to explain Everything given the tiny amount of data we have isn't going to do the trick until you have an explanatory paradigm that works better--make that works at all--which you presently have not got.
As a matter of fact, I am a panspermian, not a naturalist. But, I know the difference between speculation and science, something you apparently have a bit blurred. Until there is a reason based on positive evidence to believe in non-natural causes, no amount of bad-mouthing naturalistic explanations makes ID a better explanation than naturalist causes we do not yet grasp--something within evolutionary sciences perview.
There is an informal rule of science: never bet on miracles; it hasn't panned out once in the history of science.
It may make fetching easier, but it takes time to pack it.
So? Is DNA in a hurry to get somewhere?
Situation here is different.
Different from what? A computer program? I wouldn't make the analogy if the issues I was addressing weren't the same for both computers and DNA.
We have genes who have to be replicated exactly, that is why a lot of double checking is needed.
Not relevant. Databases do packing/unpacking and errorproofing at the same time. Lots of advantages. & by the way, we also have lots of genes that don't have to be replicated exactly.
We also have a program, and programs are never packed when being used.
Not correct. Triggers in databases, for example, operate on optimized (you'd want to say packed) data & can be themselves optimized. You are still stuck on the suitcase in the attic analogy, which is not applicable.
Since I don't know what my point was, I'm pretty cheerful about this. Science readily admits it knows very little about DNA. Am I to take that as a strike against evolutionary science or a strike against natural explanations of abiogenesis? If so, I don't see how.
Better get a note off to the curators of the Museum of Natural history at Berkeley and the editors of "Nature". They seem to have fallen behind the times on this.
Regardless, science is supposedly concerned with the truth.
truth, not TRUTH. Science is concerned to explain things in useful ways. Ptolomaic astronomy is still true, does that mean we should prefer it to Copernican astronomy?
If organisms were designed, then evolution is false.
Unless they were designed by evolving organisms. Do you claim a vaccine enzyme was not "designed"?
If the DNA code is like a computer program, it is clearly designed and could not have evolved.
Oh piffle. Lets try some more of these on. If DNA code is like earwax, we can remove it with alcohol, so it clearly could not have evolved. If DNA code is like silk yarn, we can weave with it, so it clearly could not have evolved. Give me a break.
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