Nahh. He was just joking, but the term "central dogma" did go into bio-speak anyway. It was a dramatic clarification of multiple mysteries in a single stroke.
And he very much knew about the gaps and asterisks. His Intro to Biology textbook (now obsolete) is in paragraph outline form, and there are lots of places where he summarizes what is known, and says that we really don't know what's going on there. I guess that tenured nobelists can admit ignorance.
Joe Gwinn
John Larkin's vanity seems to be remarkably effective at preventing him from following the kind of logical argument that suggests that he's ever got anything wrong.
The problem is dogma - which does put some ideas off-limits. Atheists aren't dogmatically anti-religion - they are against the kind of religion that postulates gods. That's not so much dogma as an aversion to non-evidence-based theories.
Agnostics are slightly more cautious - they merely say tat nobody has produced any reliable evidence of the existence of any god yet.
Popular, feasible and probably probable enough if you wait long enough.
Mostly because they aren't feasible. Your "improbable ideas" merely divert the question about the origin of our form of life to the origin of some other form of life which intelligently designed ours, which means that your idea is incomplete, and you haven't noticed - which is a higher level incompetence.
Francis Crick had a lively sense of humour, and it was a ironic joke. At the time he articulated it -1958 - it was a speculation, if a rather well-founded and perceptive one. Subsequent authors have shown their appreciation by repeating the irony.
False, of course. It can be improved, or unchanged, or worsened by a mutation, and it might be that a dozen 'unchanged' mutations followed by an 'improved' is rewarded by selection.
You can't insist on single-step improvement many times in a row, nor on 'worsened' and extinction as the only alternatives. It wouldn't be random if such simplifications were imposed.
By one assessment, your genome is likely to have four lethal (but recessive) genes. Unless you marry a close relative, there's no problem for you or your progeny, But, there's a lottery win possible, as well as lottery loss, depending on what combination comes up. And, that win needn't be only ONE mutation away from the general-population-average genome; it could include (for instance) four lethal, but recessive, genes.
Let me try to be clear about what you are saying. Reverse transcription has been beneficial to retroviruses, so they have kept it as a method for reproduction. That much is obvious. So you must be talking about the eukaryote side - the vulnerability to reverse transcription from retroviruses.
There you are wrong on multiple counts, due to your fundamental lack of understanding of evolution and biology.
First, evolution is random mutation and natural selection. It is not guided. It does not in any way move towards optimal solutions to problems, and certainly not "big picture" solutions. At best, it can lead to local maxima - which can also mean it gets stuck there. Every lifeform has vast numbers of traits that are not useful overall, but are artefacts of our evolutionary history.
(We have kept our vulnerability to all sorts of diseases, not just retroviruses, despite the cost.)
Secondly, whatever biochemical pathways make us vulnerable to reverse transcription could be essential to other mechanisms that are more important. You can't have mail without being vulnerable to junk mail - maybe you can't have DNA replication without being vulnerable to reverse transcription.
Thirdly, if there is enough evolutionary pressure to lead to changes to a particular problem (i.e., if retroviruses were a major cause of death), then there is no particular reason for any one given technique for reducing the problem. A better immune system that stops the retroviruses is just as good as a way to block the reverse transcription.
All in all, it is clear that there is no reason to suppose that vulnerability to reverse transcription is at all "useful" in itself in terms of being preserved by evolution. If it turns out to be useful 450 million years later, that is happy chance - not a feature of evolution.
You don't mean "horizontal evolution", you mean "horizontal gene transference" - it is still normal Darwinian evolution. And yes, viruses are a mechanism for horizontal gene transfer in eukaryotes (prokaryotes have other mechanisms that are vastly more common, but viruses could also theoretically transfer genes there). RT is not the only way a gene could be transferred horizontally. (I don't know if sexual reproduction could be considered "horizontal transfer", but we'll leave that one out!)
But even if RT /were/ the only way to transfer genes horizontally, and horizontal gene transfer lead to useful new traits, susceptibility to RT would not confer an /evolutionary/ advantage. Evolution works by natural selection - first think how likely are you to pass on your genes to viable offspring that pass them on again? Then consider those probabilities as statistics over a population, and that gives you the likelihood of particular characteristics being passed on. Horizontal gene transfer in eukaryotes is extremely rare, especially more complex ones. And like all types of mutations, the vast majority are directly harmful or deadly (local transfer of genes by RT viruses is a big cause of cancer), or at best harmless. It's extremely rare that you get something useful - such as the genes for the placenta in early mammal precursors.
Evolution is /not/ going to select for RT susceptibility on the basis of it being useful for horizontal gene transfer. It has no effect on the timescale of the natural selection function, and in the long run is mostly detrimental. Evolution does not plan for the future.
Now, as for your imagination, would you care to expand on "other uses for RT" ? Please /justify/ your suggestions.
You are mixing up two meanings of "people" here. Please don't do that. You already have a reputation for being thoroughly confused, and don't need to make it worse. First /think/ clearly. Then /write/ clearly.
Reverse transcriptase evolved in retroviruses. Modern scientists discovered it when examining such viruses, and found it useful as a genetic engineering tool.
We (and I don't know how broad you are going here - humans, mammals, complex eukaryotes - it doesn't really matter) don't have antibodies against RT because it is a protein found /inside/ a cell under attack by a retrovirus. We make antibodies against the viruses themselves.
I have tried hard here. I hope you appreciate it.
When someone has an idea, it needs to be evaluated for how it fits reality and how useful it might be. If it doesn't fit, and is leading nowhere, it must be rejected to make room for better ideas. It's a dog-eat-dog world for ideas.
Ideally, the person having the ideas can do the basic filtering themselves. You seem to be missing such filtering ability. But I've gone through the process for you here. You can take what's left and try to refine it into something better - that's one way progress is made. You can accept that the idea doesn't pan out, and drop it - then you can make progress on something else.
Or, true to form, you can ignore all the facts, information and evidence, and continue to propound your idea as if it were the best thing since sliced bread. And then you will be upset at the mocking it gets.
Yes. So?
Evolution does not plan.
For much of the history of the earth, life was very simple and changed very little. It was quite stable. Evolution does not easily lead to big changes if there is little need (it happens occasionally - it is the nature of randomness to have extreme events happen sometimes). It takes major changes to the environment to give more rapid evolution - mass extinction events, or "arms races" between predators and prey.
If you look at things from a purely self-centred viewpoint, and think the purpose of life on earth was to produce /you/, then you can well say that viruses are your friends. But evolution does not have a purpose. If there hadn't been factors challenging the survival of early microbes, life on earth would still be mats of slime - because that's how evolution works.
It is not your worst idea - at least it is not "aliens did it". But on closer examination, it goes to the reject pile. It's a pity you still don't understand the fundamentals of evolution and still don't self-filter these things. That's why you end up with the mocking.
To quote from the Wikipedia link
""" Use of the term dogma
In his autobiography, What Mad Pursuit, Crick wrote about his choice of the word dogma and some of the problems it caused him:
"I called this idea the central dogma, for two reasons, I suspect. I had already used the obvious word hypothesis in the sequence hypothesis, and in addition I wanted to suggest that this new assumption was more central and more powerful. ... As it turned out, the use of the word dogma caused almost more trouble than it was worth. Many years later Jacques Monod pointed out to me that I did not appear to understand the correct use of the word dogma, which is a belief that cannot be doubted. I did apprehend this in a vague sort of way but since I thought that all religious beliefs were without foundation, I used the word the way I myself thought about it, not as most of the world does, and simply applied it to a grand hypothesis that, however plausible, had little direct experimental support."
Similarly, Horace Freeland Judson records in The Eighth Day of Creation:[19]
"My mind was, that a dogma was an idea for which there was no reasonable evidence. You see?!" And Crick gave a roar of delight. "I just didn't know what dogma meant. And I could just as well have called it the 'Central Hypothesis,' or — you know. Which is what I meant to say. Dogma was just a catch phrase."
"""
Despite the name, it is not "dogma". When it was formed, the authors did not have enough nearly evidence to call it a "theory". And like all science, it will be changed or replaced as soon as anyone finds clear evidence that contradicts it.
It turns out that individual scientists are humans too - they use words incorrectly, or where the interpretations could be different. They pick names that sound good, even though they are not precise. ("String theory" is /very/ far from being a scientific theory.)
John's attitudes and beliefs are akin to those that annoy engineers.
John rightly gives short shrift to his (potential) customers that articulate classic nonsense such as: - mechanical: it is only few bits of string and bent metal - software: it is only a few lines of code, so you can work around deficient hardware - hardware: is is only a few wires and a micro - rf: it is only a few diodes and tracks on a PCB - comms: faster is simply a matter of more power or sensitivity
John should either accept the inverse or show intellectual humility.
Yes.
It's important to remember that the current living examples show how the current human eye (for example) /might/ have evolved - not how it /did/ evolve. We can look at a nautilus with a "pin-hole camera" eye and understand that was a likely stage in the evolution of the lens eye, but we did not evolve from modern-day nautiluses.
"Design" is a loaded word here - if you used it to mean "actively designed by something or someone", you're showing that you still don't grok evolution. If you really meant "incremental evolution", then don't write "design". Your reputation for confusion, misunderstanding, and a belief it "God did it" precedes you - if you don't want to provoke mocking, be more accurate in what you write.
What makes you say that the current modern mechanism for DNA replication is not "friendly" to incremental evolution? All you can say is that no one has proposed a plausible development pathway so far - or at fact, merely none that /you/ have heard of. (I haven't heard of one either, but I know the sum of human knowledge extends somewhat beyond my own personal knowledge.)
There are three big challenges in looking at the evolutionary history here. One is that this is all done at the molecular level and happens fast - it is experimentally extremely challenging to observe what is really happening.
Secondly, DNA as a genetic structure is extraordinarily successful. If the RNA World hypothesis is a good approximation of the early life on earth, then once DNA systems evolved they out-competed RNA-based lifeforms so completely that there are no traces left (found so far) in the modern ecosystem. There could have been all sorts of basis for life in the early history of the earth - we only know about the ones that survived.
Thirdly, the organisms of that time were very small, and there can be no fossil records as direct evidence. We have a few ancient rocks where certain minerals or patterns in the rocks can reasonably be interpreted as evidence of early microbial life, but that's the best we can get - there is no conceivable way to know if they used DNA or some precursor.
We can, however, look at DNA replication mechanisms in different living organisms to get some ideas. Roughly speaking, prokaryote and eukaryote DNS replication has some major differences as well as many similarities. There are also differences between some groups of prokaryotes. This gives a good starting point for the evolution from our common ancestor going forward. We can also look at organisms that have slightly different variations of the usual DNA base pairs (such as some bacteriophages that have an alternative form of the "A" letter). All these variations makes it clear that what we have in our own cells is most certainly not "irreducible complexity" or "all or nothing".
So how did DNA replication evolve? The correct answer is we don't know, and probably never will know how it /did/ evolve. But we can work towards better answers for how it /might/ have evolved.
Throwing our arms up and saying "it's all so amazing - it must have been a god" is not helpful. (And I don't care if you refer to a Christian god, a Hindu god, an alien robot, intelligent DNA, conscious electrons, or any other super-natural super-powerful super-intelligent super-designer - it's all the same principle with different names and different details.)
Yes, it's amazing stuff, and fun to watch. It does not in any way collaborate your idea.
I hesitate a little with this analogy, because I fear you may misinterpret it, but let's look at something that very clearly /was/ designed - because it is man-made. Have you ever watched a modern pick-and-place machine in action? You have a big device that is placing millimetre-sized components at rates of 30 per second. The machine is dependent on a whole range of subsystems - feeders, arms, control boards, visual inspection systems. Remove or change any one of these, and it won't work. But would you consider it "irreducible complexity"? Would you say it was designed as a whole, from scratch? No - you can understand how it "evolved" from previous generations of pick and place machines, going back to earliest models that were using ideas and designs from completely different systems. The ratchet mechanism used to feed from component rolls can be traced back to pendulum clocks - an utterly different kind of usage. The placement arms can be traced back to human arms.
The point is, just because something is impressive and complex, does not remotely suggest that it cannot have developed gradually from simpler systems.
Correct. There is solid evidence, experiments and plausible pathways for many parts of the journey, but far from all of it. Science is a work in progress - but that doesn't mean you get to fill in the gaps with fairy tales.
It is accepted as a work-in-progress hypothesis - because that is what it is.
No, there are other work-in-progress hypotheses for abiogenesis. I think the RNA World is probably the front-runner, but it is not the only one being considered and no doubt other ideas will be considered in the future.
But scientists don't bother with "I give up" as an answer. "We don't know" is fine, as long as it is "We don't know /yet/" - with "We will probably never know for sure, but we can maybe find plausible hypotheses" as a fall-back. Science does not bother with "God did it" or other kinds of magic - if you want that, find (or found) a suitable religion.
Yes, scientists are human, and usually dislike been proven wrong. They /do/ like proving other scientists wrong. But the emphasis is on the word "prove". Random thoughts do not /prove/ anything. None of your "ideas" has had the faintest shred of evidence. The RNA World researchers are unlikely to find much evidence for what /did/ happen, but at least they find evidence for what /might/ have happened or /could/ have happened. And if anyone finds evidence - historical or experimental - that contradicts it, the hypothesis will be disproved.
Come back to us when you have /evidence/ for your ideas. "I can't imagine how that would have evolved" is only evidence for your own lack of knowledge and imagination - it is not evidence for your ideas or evidence against real research hypotheses.
And remember - extraordinary claims require extraordinary evidence. If you want to prove conventional theories of Darwinian evolution are wrong, you'll need overwhelmingly strong evidence to counter the vast evidence we have that supports it. And when you come with absolutely nothing, you can expect to be mocked.
It has also been suggested that the moon has played a major part in the development of life beyond the microbial. As well as tides giving a good balance between relatively stability in coastal environments with enough mixing to spread nutrients and useful chemicals, the moon has kept the earth's rotation balanced and the 23° tilt stable. Modelling has shown that this tilt would have varied far more chaotically over earth's history - causing disruption in the seasons and climate. Advanced life - and especially intelligent life - probably requires stable periods.
(Asimov used that idea in his Foundation series. When people were trying to find the ancient birth planet of the human race, the legends told of a planet with a huge moon - something they found hard to believe.)
What is your basis for calling it "improbable"? Ignorance? Something you read in one of your "intelligent design" books by authors looking for new guidable pundits when their homeopathy business is waning? Something you saw online that had lots of big numbers and calculations, so you assume it must be right?
Improbable ideas can be considered, if they give something useful, have evidence, are rational, and might lead somewhere. Impossible or magic ideas with no evidence or justification need not apply.
I don't think John realises that in science the prize does /not/ go to the originator of an idea.
The prize goes to the person(s) that provide /evidence/ that /convinces/ others.
And that's as it should be, since the alternatives are unworkable.
You're not interested in biology or cool mechanisms or design, electronic or other wise. You certainly don't delight in ideas or fun machines, or much of anything as far as I can tell.
You hate ideas and speculation.
You seem to delight only in insults. You are just a bitchy old hen.
Maybe you are sick or something. That makes people depressed and crabby.
Why start now?
That's mere repetition of your same old tired tropes, indicating that you are unable and/or unwilling to listen, think, change your ideas.
Maybe /you/ are sick or something. That makes people depressed and crabby.
You won't start to try to understand the position he expounds.
He is making a valiant but doomed to attempt to understand your position.
The position he expounds is that I'm ignorant and stupid. I confess that I don't understand that.
I see no attempts to understand anything. Just reflex insults.
My position, and my profession, is to be curious about systems and ideas, and to consider possibilities no matter how whimsical or apparently improbable, because they might turn out to work, or might be a path to other ideas, or just because they are fun to think about.
That attitude sure seems to offend you and your buddy. Expert biologists like you seem to be a dogmatic lot.
Heh. As I mentioned elsewhere, calling it the Central Dogma was a joke, intended to brush back just those above folk. But I'll grant that maybe the joke worked rather too well.
Sort of like how the Big Bang was named.
.
Joe Gwinn
The classic example was Newton's persecution of the fellow that discovered the achromat lens. Newton had declared chromatic aberration to be impossible to remedy (which is why he invented the Newtonian Telescope), only to be refuted by this upstart, whom he destroyed. This endured until Newton's death. (from the SED thread "Edison Did Not Invent Light Bulb!" in May 2013.)
Joe Gwinn
Since Newton wasn't a scientist - the word wasn't coined until 1833
"Science progresses one funeral at a time." is a paraphrase of something Max Planck (1858 to 1947) wrote. Some of his contemporaries did behave that badly, but Planck himself was remarkably open-minded.
Scientists want other people to exploit the work they have done. Newton probably invent calculus, but he called it the method of fluxions, and didn't teach it to anybody else.
That is a classical example of scientific behavior (though Leibniz wouldn't have called himself a scientist either).
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