Re: New Cellular Evolution Theory Rejects Darwinian Assumptions
Posted by Ben on Jun 27, 2002 at 15:36
(211.170.79.28)Re: New Cellular Evolution Theory Rejects Darwinian Assumptions (Andy™)
It's almost as possible as the original, too. Honestly, let me break this down to see if I'M misunderstanding it.
You are misunderstanding it.
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.
...How? One of these things is one way, one is another, one is another, and so on.
Bacteria even today tend to trade genes. The bacteria are simple, and the membranes that separate them are small. Genetic information can enter an organism and be incorporated into it's genes rather easily. This is called lateral gene transfer.
I hardly think they could benefit each other in any way at all. This is being described as if this pool of non-cells was one organism, supporting itself. Ridiculous.
Really. Point mutations are much slower at building new complete protiens than simply incorporating the complete finished code for the protien from another species of bacteria. Think about how we insert new genes for spider silk into goats (lately in the news). What these guys are saying is that this type of gene transfer happened all the time in pre-multicelled bacteria. If one bacteria slogged its way step by genetic step to developing a new enzyme, another could simply steal the enzyme from its competitor by incorporating part of its competitor's DNA. Since bacteria are perpetually randomly incorporate bits of DNA from other bacteria even today, it's natural to assume they did so back then too.
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.
And yet the fundamental problem of what gave them their start is still ever present. How was there horizontal gene transfer when genes didn't even exist?
There wasn't. That's like asking the question of how horizontal gene transfer is supposed to work for humans. Wrong question for the wrong subject. Ask instead about how early self-organizing chemical metabolisms developed as dissipative structures in volcanic vents instead. But don't ask these guys, as they're studying the evolution of microorganisms, which occured perhaps a half billion years after the origin of life.
A pool of sugar water won't do the trick. It had to start somewhere, and even then the chances of the non-cells created being able to aid each other are quite unlikely, are they not?
No, but a pool of reactive thioeters reacting with sulfer ions near ancient volcanic vents might. But again, you're off the topic of lateral gene transfer, which occured perhaps close to a half billion years later. You jumped past the primitive replicating chemical system stage, RNA world, simple precellular membrane systems, etc. and started talking about complex single celled organisms.
Consider that no statement on how these non-cells were aiding one another or what chemicals they were passing to each other is given.
It's just a science article for laymen. Why don't you do a search on the associated literature.
Cellular evolution, he argues, began in a communal environment in which the loosely organized cells took shape through extensive horizontal gene transfer.
Started impossibly at the perfect time, in the perfect place, in the ideal setting on an inhospitible orb, completely at random with no aiding organization from outside the system. Again, how were the initial genes developed? He doesn't say.
You are missing the point. He's not talking about abiogenesis at all. He's talking about cellular evolution. Cells are highly evolved creatures that are the products of vastly more evoutionary time than multi-cellular animals. They've been around for about 2 billion years or so.. mutli-cellular life has at most been around for 600 million. Cells evolved from primitive pre-cellular systems that "probably" started at submarine volcanic vents. From that point onwards, there are three main cellular families, archea, eukaryotes, and prokaryotes.
What these guys are saying is that, since their original division from a common ancestor, they have been mutually evolving, trading genes, etc. until their true ancestry is a mish mash of interconnected mush.
With simple primitive entities this process can "completely erase an organismal genealogical trace."
And in a pre-genome setting this has no meaning whatsoever.
Absolutely correct, because that is not the subject being discussed.
All we have are non-cells existing alongside one another passing chemicals and amazingly fortunate in their own origins.
Perhaps amazing fortunate, or perhaps the product of the inevitable laws of chemistry, thermodynamics, and probability. But since the article is not about abiogenesis, it doesn't matter.
..none the less, they somehow came together and even started creating genes all on their own with no programming of their own like a cell has, which tells them how to do what they do.
Who tells a chemical polymer formed during a catalytic reation in a plastic plant "what to do". It does what it does because of the energy differentials of its atoms, linking together to form polymers that make great cups, toys, and other nice things. All that's needed is the heat, the carbon atoms, and the location where they are brough together. Chemistry does the rest.
Granted... but should it go from Common Descent into randomized soup? On it goes... Referring to his attainment of the Medal of Science, which is impressive considering this recent work.
Tell me, please, how does this solve the problem of how these non-cells came to be in the first place? Chemicals randomly coming together can happen, but that doesn't give us life. Self-assembling crystals are one thing, Complex organisms are another, and any organism is bafflingly complex.
It doesn't explain this, nor was it meant to. Self-assembling crystals are one thing, self assembling polymers and catalytic reations in chemical systems far from equilibrium are something else. It simply takes faith to believe that these spontaneous reactions could never produce what the giant "hint-hint" arrow of the history of evolution from that point on clearly indicates occured.
So now instead of having one organism to evolve, we have multiple, in a close location, all contributing to one another's development. How they do this, where they came from, how they came to be... are all un-answered questions.
Unanswered, but perhaps not unanswerable.
You can simply deny that the shrinking complexity and diversity that we see in evolution back to three billion years ago implies that we started with simple repeating chemical reactions, but that seems to ignore the rest of 3 billion years history.
If we know that all multi-cellular animals evolved from previous animals, and then single celled animals, and they in-turn evolved from simpler combinations of membranes and self catalyzing RNA (as is strongly implied by RNA's ability to catalyze itself), do you think that suddenly this process just stops because we are no longer able to trace it? Does a person walking behind a wall suddenly disappear simply because you can't see him? No.
And yet it's called a theory. Experimentation? Anything? Anything at all?
Likewise, just because you don't know of any experiments doesn't mean they don't exist. Why don't you read up a little on the research into pre-biotic life Andy. You might be a little suprised.