Mokele

Scrappy has been permanently banned due to persistent fallacious arguments and general intellectual dishonesty. And there was much rejoicing.

I'm happy to report that scrappy will not be continuing this, or any other, argument on this site due to well-deserved application of the permanent banhammer.

I agree with Sisyphus - you've watched WAY too many movies. Have you seen the homicide rates for the worst cities in the US? None of them even had 50 murders in all of 2007, and that's in cities with populations of nearly 1 million. New York city homicides in 2007? 6. That's it. 6. You're trying to solve a problem that simply doesn't exist.

Your quote only specifies "genetic information". It says nothing about it being digital. It say nothing about tRNA or codons. It doesn't even say anything about genes. This quote does NOT show why an organism which uses ribozymes for catalysis with their sequences stored on DNA, with no proteins even involved, wouldn't be 'alive'. Failed. Try again.

Reference, please. Because that's how science works. References, again. I've never seen the supposed "oddity" of recent years explain as anything but a stastical anomaly, the sort of random "blip" you get in any complex system. Yes it can. Easily. Go on, read the graph. Really read it. Now read your reference. Notice anything? The graph ends in 1990, and sulfate forcing levels off before that, around about the early 1980's. The study you quoted references the period from 1980-2000 only. These two are not contradictory.

I'm going to give you one more chance: Give even ONE reference which claims that the code is REQUIRED for something to be considered 'life'. You made the claim, you back it up.

Beats the hell out of me. Nothing sensible.

For the same reason birds lack teeth - because any previous forms are extinct. And before you continue your griping about this, consider the alternative: either life formed all at once, in a single, spectacular "poof" moment, or it formed in piecemeal fashion and the previous forms are extinct. Any intermediate steps, either in evolution or abiogenesis, were actual organisms or proto-organisms. The absence of a current representative of an intermediate form can only be explained by extinction, parallel evolution, or the putative form having never existed in the first place. Therefore, if you accept the presence of *any* intermediate stages, and that they do not exist anymore, you have only two options, neither of which support your claims. Something you might note: Mitochondria deviate from the "universal" code, as do Mycoplasma and Candidia. These indicate the code is not so permanently fixed. Mitochondria in particular are interesting, as they have relaxes selection pressures since they live inside other cells and only have a handful of genes. Of course, the two hypotheses are also not mutually exclusive - Stereochemistry could be responsible for the original code, and Frozen Accident for its maintenance. It's also worth asking how many animals have we really actually *checked* the code in, rather than just assuming it's universal. The presence of deviations (admittedly minor) in free-living organisms, including a eukaryote, suggests that there may be other deviations in the hundreds of millions of living species.

I bet you can't imagine a fish with jaws like a pair of serrated scissors, or an animal with five eyes, but they existed. I've explain this to you repeatedly - you cannot simply assume that what exists today is the only possibility. And each time, you acknowledge it, and then within a week completely forget it and bring up this tired old argument. You agreed that my hypothesized series of events is "plausible". By any definition of "life", even an organism which just has ribozymes and stores their sequences on DNA is "alive" - it can metabolize, grow, reproduce, mutate, maintain homeostasis, respond to stimuli, etc. It could presumably do anything a modern living organism can do. It would be alive by any currently accepted definition, but would have lacked "genes" in the sense you describe them (though I also disagree with that definition, and would consider the information in the DNA that's transcribed into ribozymes to be "genes"). Of course, I can't point to a living organism that does it, but you also cannot prove that it's not possible. Your entire premise rests on the idea that what is currently alive is the only possibility, and has been repeatedly and amply refuted. You want to claim that the definition of "life" requires tRNA and codons, then cite a peer-reviewed paper claiming that.

Why not? Why does the definition of a gene *require* that tRNA be involved? Just because that's what we see today? That's like saying birds are defined by lacking teeth, just because all the extant lineages are toothless. You're confusing what's around today with what's actually necessary, functional, and possible. I disagree - I think codons, the use of tRNA, etc. happened *after* the origin of life, and that organisms prior to that innovation were already "true life" by any reasonable definition. I agree that it's an interesting question, but I disagree that it's necessary for life, and that organisms before it were somehow "not alive" just because they didn't do things exactly our way. Mokele

Um, no. Not even close to true.

Yes, you would be allergy free...for about 2 months. At that point, you'd nick your finger while making dinner, get gangrene, and die a horrible, painful death.

I laid out an entire hypothetical transitional sequence for you in post #44.

Thread temporarily locked. Merged post follows: Consecutive posts mergedThread unlocked. Everyone play nice, and cut the infighting. If you have a problem, report the post and we will deal with it.

It's the price of a high metabolism. Basic cellular metabolism produces by-products which damage DNA, and because we're so turbo-charged (our basal metabolic rate is about 10x that of a reptile of the same mass) we produce a LOT more of these DNA-damaging by-products. Thus, in order to prevent us from dying of cancer, we had to lose a variety of useful traits, like telomerase and regeneration.

Telomerase is only one of the things necessary for a cancer cell to be truly cancerous. Numerous other mutations, primarily to the genes controlling cell division, are necessary.

That could be more possible, though of course massive morphological and physiological changes are still needed.

Or you can just orient it vertically and prop it up.

Technically, Pterodactyls were the size of sparrows. You're thinking of pterosaurs, particularly the big azhdarchids like Quetzalcoatlus. The problem isn't that things as big as us *can't* fly, it's that the level of modification required to make it possible is so dramatic that the person could not really be called human anymore - literally every aspect of their morphology and physiology would need to be altered. No person could ever survive such alterations. As for nanotubes, the strength of bone really isn't the limit. The problem is more the limits of muscle (and no artificial muscle can even come close to the real thing). Muscle has limited power output, which limits wing movement and thrust, which limits speed, which limits lift, which limits flyer weight.

Precisely. It's also why you need at a minimum of two different photoreceptors to see color - with only one, you can't tell if reduced stimulus is due to different wavelength or just reduced light levels.

But what would you call an organism that transcribed mRNA by AA binding to the actual nucleotides? Why is that not "alive" when a descendant that uses tRNAs is? True, mutation would be a better criterion. But then why would something that uses analog means not be alive if it metabolizes, mutates, grows, and reproduces? The point is it's just a metaphor, good or bad. A semantic argument is the lowest form of argument.

Nerves don't fatigue, AFAIK. Also, maximal stimulation isn't the result of using the same nerve cells more, but rather using additional nerve cells that weren't in use in less strenuous exertions. The beneficial effects of exercise aren't due to nerve use, but rather related effects like hormone and blood sugar levels, metabolic rate, etc.

Why couldn't RNA world have been analog, then digital? If it started out with ribozymes and nothing else, it would have been "analog", much like how a prion makes new prions. But then DNA could have developed, to store the ribozyme in a 1:1 copy that's more stable. At that point, you have a 'cell' with stored information that's literally and directly translated into metabolic machinery. Some experiments have indicated that codons aren't purely arbitrary, and that the corresponding amino acids preferentially bind to the DNA of the 'right' sequence. So maybe from the DNA->RNA life, you can get DNA->protein life, where the DNA is a direct reflection of AA sequence. From there, mRNA probably got involved (with proteins directly attaching to it), and from that, tRNAs. Of course, that's all hypothetical, but IMHO it's plausible and there's some key experiments that support certain aspects, though of course a LOT more work needs to be done. Merged post follows: Consecutive posts merged Isn't fulfilling the criteria (metabolism, reproduction, growth, evolution, etc.) what defines an organism? (see the perennial 'is a virus alive' debate). And a muscle isn't a motor and differs in a lot of very important ways, but we still talk about motor neurons, motor units, etc. It's a metaphor. Whether it's a bad or good one is utterly irrelevant. You're just arguing semantics. Move on.

Yes, but remember that many of us live in a country with a higher per-capita murder rate than Ethiopia. The use of remote-operated machines is possible, but there are serious technological hurdles - no machine yet is simultaneously as fast, as nimble, as manuverable, as dextrous and as strong as an average human. Agility and manuverability in complex environments are particularly difficult robotic tasks.

The resolution you cite doesn't support your claims, which I think are entirely fictional. And it is *your* job to support any claim you make. Now support it or retract it.