Did viruses precede other life?

If we continue our Victorian line of thinking in categories, then you'll probably conclude that viruses did indeed come first.If, by life, we mean cell creatures, viruses being much smaller chunks of "life's" main code - cheifly RNA/DNA - must have been in existance befor our little cell friends even "come into existance".After this "event", you would be correct to think that viruses actually come from celled creatures; being breakaway strands of RNA that slip through the cell walls and out into the great wide world.What I find interesting about viruses is that you only know you've got one, when your body doesn't like it - you get a cold, or flu, or worse.But what of those little blighters that DON'T raise an rash, not a hair! What of those genes/DNA/RNA being transfered b/w GM crops to non GM crops, or brought into our bodies through digestion and into our cells?Some call this horizontal transfer. Other might call it evolution.Sean

Bascially, yes, horizontal transfer of genetic information by viruses is the major driving force behind speciation/"evolution".Although viruses are seen as a pest, they are genetic mechanisms; so a virus is a carrier of genetic information. When they assimilate with host DNA (as we see with HGT in GM foods) they have "evolved" the host. They have inserted their "viral-gene" into the host.But, an "evolved" host doesn't mean a gene-expressing host.The virus could lay dormant for many generations before activator genes (situated in highly volitile/sensitive regions of DNA) accidently trigger our new viral-gene. When that happens we have two outcomes 1)Death of the organism because of the viral-gene's effect, 2) successful assimilation with host's machinery (and possible benefits that could bring).So, we have two types of "evolution" going on. 1) a sort of genetic macro-evolution with HGT, and 2) a genetic micro-evolution, with activator genes expressing the viral gene.Speciation, you would then understand, would be a mixture of new viral code insertion and/or the *loss* of genetic code, and adjustments to gene activation by activator regions."Survival of the fittest" would then decide which organism used their normal and viral genes to the most effective outcome (greater multiplication, more resistance, longevity etc you know what i mean).Sean

Look, for God sake if you don't understand what I'm saying read the damned website! The major issue here is your "belief" that micro-evolution by genetic allel mutation actually provides real beneficial change to the genetic structure. IT DOESN'T! Genetic faults are VERY RARE!! Yes, you see organisms with problems, (i.e. sickle cell) but consider how many hundreds of billions of cells YOU are made out of, and each person is made out of, if so-called micro-evolution had any MAJOR effect on the genetic code, it would be obvious! Cells within us would have different genetic code!Get out of the dogmatic BOX! Read the website, at least read the Whats New section to see the gradual build up of evidence. You are an intelligent person, i can see that, but don't let yourself be trapped. The only way out is to read. You've said yourself before you haven't read much about it. Read about it and come back.I have to say its very interesting talk to you because you make me think.

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Doesn't seems to me that this genetic macro evolution by HGT would have a different effect phenotypically than normal mechanisms of genetic-microevolution

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HGT transfers WHOLE WORKING GENES! WHOLE PROTEINS! Whole TOOLS that the cell can use. Micro-evolution provides single allel mutations, that will invariably destroy protein effectiveness (i.e. sickle cell) and the probably the organism, if it ever gets past gestation.

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since the activation of a H-acquired gene would depends of a regular mutation, which could "hit" any non-expressed gene that came to existance by mutation too

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1st u've made an assumption that muation occurs only on non-expressed portions of the genome. Thats wrong. When it does happen it will happen more likely to expressed "working" regions.However, you've made me think a little. I would reply this:Again, random mutation is VERY RARE! The repair mechanism of cells are extremely efficient. You will notice that genetisists say there are regulator regions which change more frequently. Those areas of the genomes which ARE frequently altered via "mutation" seem to be under directed alteration by the genome itself. As yet I haven't come across a piece of research that documents the genetic alteration of a genome by "self-mutation" (except for the rearrangement of genes in general) but I think thats because no-one is looking for it.

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I don't understand much of this

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Look, please, following this link and read just this one page.
Interesting links on it are* More about photosynthesis by gene transfer
* Gene transfer among eukaryotes
* Halobacteria can repair badly damaged DNA
* More animal genes came from bacteria
* Microbes have stolen some of our genes!And more.What'sNEW in Cosmic Ancestry. by Brig KlycePanspermia is a beautiful theory. And if you're interesting in quantum physics and organic systems, its even more amazing theory than the pure genetics side can "see".Sean

Hi ooookHere is some evidenace from What'sNEW in Cosmic Ancestry. by Brig Klyce

Read a little more. I'm saying that genetic allel mutation occur very rarely.

No, allel mutation is not cupious. A lot of mixing occurs due to fertilisation, but mutation of allels does not occur often. Don't get the two confused.And you can't talk about over the lifetime of a population. thats doesn't make sense. Of a species, well, yes, mutation of allels does occur quite often over millions of years or so, and most die because of it, so are a hinderance to evolution (or a benefit, as that mutation was deleted and not passed on).This message has been edited by SUnderwood, 09-29-2004 02:04 PM

I take your point. Synonymous substitutions is more frequent than I had thought. But codon substitutions is still deleterious. The paper to which you refer is interesting in its conclusions, that amino acid substitution is deleterious, whilst nucleotide subsitution (depending on its synonymity) is not, necesarily. My apologies, I have mixed up the codons and allels. Thank you very much for the reference.The paper referenced does howver provides support to the argument, that evolution, at the protein level, is a rare event, and that nucleotide mutation (and so codon change) is usually damaging. HGT, then, is still a major source of genetic information.BTW, did u read the list of references which I posted?