Darwin re-visited

[Biochemist]

No abiogenesis is not hard to model.....

I particularly loved this one.

[Moontanman]

If only I knew everything.I think I agree with the second part of your point, but not the first. You are going to honestly say that we got the first self replicating life form with our four nucleic acids and 20 amino acids in the roughly 500 million years between when the earth cooled and 3.5 billion year ago????? Completely randomly???? Did it happen seven more times (in nearly exactly the same way) since???? Heck, we have had time and the environment is a lot less hostile now. Why aren't there a half dozen common descent trees? Get real. This is a perfectly reasonable position as a hypothesis, but it is not high on the plausibility scale.I don't look at creationist web sites. I leave that to you unbiased scientists.

 

 

Just the fact that you can actually say this shows you have no clue what so ever and are simply parroting creationist web sites. Sad really sad......

[Moontanman]

I particularly loved this one.

 

It's not, do some real research, read something that was published by real scientists less than 20 years ago. Creationists have been using the same arguments for many years not knowing they have been relegated to quoting out dated literature, you are so guilty of that dude.

[Biochemist]

Just the fact that you can actually say this shows you have no clue what so ever and are simply parroting creationist web sites.

Silly me. And I was under the impression that to "parrot" something, I would actually have to have seen it.

 

I must be really good.

[Moontanman]

Silly me. And I was under the impression that to "parrot" something, I would actually have to have seen it.

 

I must be really good.

 

No really bad would do.

[Biochemist]

It's not, do some real research, read something that was published by real scientists less than 20 years ago.

This is really just so straightforward. Attached is a summary review of the status of abiogenesis research as of 2005. It is a little simplistic, but hence pretty readable. It reasonably summarizes the evolution (no pun intended) in thinking from the original Miller experiments 50 years ago through the current debate between "metabolism first" and "genes first".

 

The simple summary is that no one has a good idea how it happened yet.

 

abiogenesis.pdf

 

Really only a ten minute read. But it does not address the core critique: If either of these core processes were the original process, why would it not have started multiple times, and hence created multiple "common" ancestral trees?

 

I don't have an answer to this either.

[Moontanman]

This is really just so straightforward. Attached is a summary review of the status of abiogenesis research as of 2005. It is a little simplistic, but hence pretty readable. It reasonably summarizes the evolution (no pun intended) in thinking from the original Miller experiments 50 years ago through the current debate between "metabolism first" and "genes first".

 

The simple summary is that no one has a good idea how it happened yet.

 

[ATTACH]2568[/ATTACH]

 

Really only a ten minute read. But it does not address the core critique: If either of these core processes were the original process, why would it not have started multiple times, and hence created multiple "common" ancestral trees?

 

I don't have an answer to this either.

 

Rehash of out dated information dude, try reading "Life as we do not know it" by Peter Ward and maybe you get a starting point to discuss this. read that one and I'll direct you to more education sources. Lots of new stuff and guess what no problems at all with abiogenesis and the one genome "problem" You really are operating with out dated info, lateral gene transfer can explain no multiple ancestral trees. On top of that if there were multiple trees we would would have no way to know it. We don't ever check for life other than the one one we know. There could be multiple trees and we would never know. All we know it that only one tree resulted in complex life forms. so we check for organisms like us, others are not checked for. Check out the science news section of this site for more info.

[Moontanman]

Bio, a few things for you to chew on.

 

http://hypography.com/forums/news-in-brief/17772-origin-life-earth-simple-fusion-jump.html

 

http://hypography.com/forums/news-in-brief/18007-how-did-life-begin-rna-replicates.html

 

http://hypography.com/forums/news-in-brief/17875-review-why-evolution-true-jerry-coyne.html

 

http://hypography.com/forums/news-in-brief/17731-earths-original-ancestor-was-luca.html

[HydrogenBond]

Evolution does not currently do a full energy balance. It sort of goes from the beginning of the energy hill implicit of a mutation, to the end, which is selective advantage. This makes the energy curve look like it occurs with particles in quantum physics, where we get quantum jumps in space and time. What we know of life is based on chemistry which has a continuous curve. I would still leave open the quantum physics aspect, but we first need the chemical energy balance of evolution 3.0.

 

Life takes energy to work. Cell cycles, where most of the mutations appear to occur, occur when the cell is using the most energy. I am not making this up. You can explain some of the logic of speciation using an energy balance.

 

If we start at a fertilized ovum. This is a high energy potential state. This can be inferred from the observation that it will take a lot of energy to drive the many cycles of cell division leading to the blastosphere. This energy appears contained within the ovum. The energy curve sort of looks like descending stairs, with the initial potential energy stepping down all the way to the final division, 128 cells later.

 

If we go back to the top energy stairs, at fertilization, when the male and female DNA combine the genes, shuffle. Once the genes finishing shuffling, the descent down the energy stairs begins. The shuffling appears to allow the composite to finish climbing the energy hill.

 

Most cells have more DNA than is needed for all the proteins they make. Relative to speciation, among this extra DNA would need to be genes that have accumulated, but which are not required for the proteins of the starting species. If the high potential shuffling process moves enough of these genes to the front, the result is a new species.

 

The question is, would bringing a lot of new genes to the front create a lot of extra potential within the growing embryo, since many or even most of these may not have had time to be integrated? The answer is yes. This is where stem cells come in. A multicellular critter has the advantage of spreading out the work load to distribute new genetic potential to hundreds of differentiated cells. Each only has to deal with few tasks, which is do-able. Each differentiated cell buries the rest.

 

The analogy is a CEO with a pile of work on his desk. It is overwhelming if had to do it all by himself. He gives a pile to each of his VP's. They give smaller piles to each division head, who give smaller piles to each department head, which gives little piles to each group leader, to spread out among the members in their group. Now it is easy. The energy potential of the original shuffle lowers because of this process even before we begin the task of doing anything. The first generation of a new species will still have bugs so it may take several generation to iron out all the bugs and stabilize.

[Biochemist]

It's not, do some real research, read something that was published by real scientists less than 20 years ago.

Moon- I really do think you have some thoughtful input on this topic, but I would really prefer it if you would remain positive and not drop into personal attacks. I responded to this request with a summary from 3 years ago, and got blasted for my foolishness again.

 

Please interact respectfully.

[Biochemist]

Rehash of out dated information dude, try reading "Life as we do not know it" by Peter Ward and maybe you get a starting point to discuss this. read that one and I'll direct you to more education sources.

Will do.

Lots of new stuff and guess what no problems at all with abiogenesis and the one genome "problem" ......lateral gene transfer can explain no multiple ancestral trees. On top of that if there were multiple trees we would would have no way to know it.

Suspicious. We would be pretty likely to find aberrant RNA, DNA or non-standard amino acids if they were coded.

There could be multiple trees and we would never know. All we know it that only one tree resulted in complex life forms.

This is a bit of an odd argument. You are modifying the standard common descent argument to apply only to higher forms of life, not lower?

 

If there really is only one common descent tree that generated higher phyla, aren't you saying that there is only one tree (out of what trillions? Quadrillions?) that had the propensity to generate higher forms? Wouldn't that mean that there was exactly one tree biochemical architecture with, for whatever reason, a substantially higher propensity to diversify? Are you really just saying that the propensity to diversify was front loaded in the first life form in the tree? Aren't you making my arguement for me?

 

Further, if the argument that the basic primordial substrates (ammonia, hydrogen, etc) are all that is required to assemble a single unique diversifying tree in 500 million years, does it not follow that any planet like earth (should we find another "class M" as Captain Kirk would say) would have very similar diversity based on the same tree?

[Moontanman]

Will do.Suspicious. We would be pretty likely to find aberrant RNA, DNA or non-standard amino acids if they were coded. This is a bit of an odd argument. You are modifying the standard common descent argument to apply only to higher forms of life, not lower?

 

Putting words in my mouth bio, I didn't say that, all I said was as far as we know only one tree resulted in complex life forms. You are also equating success with complexity, this is not true.

 

 

If there really is only one common descent tree that generated higher phyla, aren't you saying that there is only one tree (out of what trillions? Quadrillions?) that had the propensity to generate higher forms? Wouldn't that mean that there was exactly one tree biochemical architecture with, for whatever reason, a substantially higher propensity to diversify? Are you really just saying that the propensity to diversify was front loaded in the first life form in the tree? Aren't you making my arguement for me?

 

Again you are distorting my words to your own ends, I didn't say that I said if there were other trees, I said nothing about trillions or quaddrillions, all I said was as far as we know "if" there were other trees apparently they did not result in higher life forms. Doing a little research would really be a good idea Bio.

 

 

Further, if the argument that the basic primordial substrates (ammonia, hydrogen, etc) are all that is required to assemble a single unique diversifying tree in 500 million years, does it not follow that any planet like earth (should we find another "class M" as Captain Kirk would say) would have very similar diversity based on the same tree?

 

In early life lateral gene transfer merged all life together until eventually organisms emerged that were all an amalgam of the basic free metabolisms that filled the oceans. If a tree developed that was too different for lateral gene to occur we can surmise a few things about it.

 

First it is evident this tree didn't result in complex life forms. Secondly if it is different we would not see it in any of the tests that are currently being done (a new test to check for different life forms has been suggested but not acted on as of a year or so ago) Such life would go unnoticed completely in any and all test for Life at this time. Personally I think the theory that RNA viruses are a faint shadow of another tree of life is plausible but it is highly debatable.

 

If indeed there is another tree of life then it would follow it was not as successful as the one we know, at least to our judgment. Saying that to be successful would result in complex life forms is assuming life has a direction a purpose, it does not. The most successful organisms on this planet both in number and in actual bio-mass is bacteria, eukarotes don't even come close to winning that test.

 

It could very well be that another tree of life is quite successful and has organisms in places our form of life cannot survive or even co-exists along side our own form of life. We may even have seen such microbes in microscopes or even as colonies but as I said before any test would only indicate life as we know it. a microbial mat containing both types would only show our life not the odd life when tested.

[Biochemist]

Putting words in my mouth bio, I didn't say that, all I said was as far as we know only one tree resulted in complex life forms. You are also equating success with complexity, this is not true.

Sorry, Moon. Didn't meant to do so. But it seems to me that you have to fish or cut bait here. Either there is a biogenesis mechanism that was narrow enough to significantly skew the outcome toward a single "preferred" tree, or there should be evidence of a number (probably a very large number) of different unrelated trees. If you pick the former, you are allowing for the possibility that the tree that surfaced is somehow uniquely likely to diversify. If that is true (since it seems to fit the data), then that unique tree had unique propensity VERY early in the tree, since there is no evidence of other trees.

 

If that is true, the unique tree is "front loaded".

[Moontanman]

Further, if the argument that the basic primordial substrates (ammonia, hydrogen, etc) are all that is required to assemble a single unique diversifying tree in 500 million years, does it not follow that any planet like earth (should we find another "class M" as Captain Kirk would say) would have very similar diversity based on the same tree?

 

Captain Kirk existed in a fictional universe based on the idea that once life started it's climb to complexity was assured. Now days we know that complex life needs some really narrow constraints, there is a school of thought that contends that life is a natural part of the development of almost any planet. In other words at come point in the development of a planet life is almost certain to occur. In many cases that life is snuffed out by environmental conditions that go beyond the parameters that allow life to exist.

 

Complex life is a different set of life, complex life needs specific conditions of temperature, atmosphere, steady conditions that on most planets simply do not exist long enough for complex life to develop. Earth developed complex life after 3 billion years of nothing but microbes. The reason for this was the conditions of earth were no conductive to complex life forms until the last billion years or so. If indeed eukarotes had not been waiting in the wings the Earth might still be a microbe planet.

 

You seem to be stuck in the mindset of life naturally develops from simple to complex and that complex equals multicellular life forms. common bacteria are very complex compared to the first life forms. all life on the Earth is just a evolved as every other life from om the planet. Bacteria, are just as evolved as humans, in just another way. No life form is superior to another due to size, complex life is not superior to microbes, just different.

 

Indeed it is possible that the Earth and it's complex life is a very rare occurrence, possibly one of only a handful of planets with complex life in our galaxy. If this is true, then extinction takes on a whole new meaning and becomes a horror of much greater magnitude than we know.

[Biochemist]

Again you are distorting my words to your own ends, I didn't say that I said if there were other trees, I said nothing about trillions or quaddrillions, all I said was as far as we know "if" there were other trees apparently they did not result in higher life forms.

I think I read you correctly. You said (and I think you are correct) that there is no evidence of other trees. My suggestion was that the lack of evidence is probably indicative that there are no other trees (as least not that lead to higher phyla). This suggests that the one successful tree was somehow favored.

 

And I was the one that brought up the "quadrillions" point. If the early oceans were the original "breeding grounds" (if you will pardon the metaphor) for biogenetic precursors, the nucleotides would (reasonably presumably) have been broadly distributed. If we assume (for example) that there were 1000 seminal macromolecules in each milliliter of the top 30 feet of ocean (to give access to sunlight, again assuming that UV or heat was necessary) that would be approximately 3.3 x10^21 seminal molecules. "Quadrillions" in this context is pretty conservative. You are suggesting that the lateral transfer mechanism "merged all life" together. You have to admit that this is a pretty long way from a sure thing.

Doing a little research would really be a good idea Bio.

Courtesy, Moon.

If a tree developed that was too different for lateral gene to occur we can surmise a few things about it.

 

First it is evident this tree didn't result in complex life forms. Secondly if it is different we would not see it in any of the tests that are currently being done (a new test to check for different life forms has been suggested but not acted on as of a year or so ago) Such life would go unnoticed completely in any and all test for Life at this time.

This is a bit of a faith statement. It might go unnoticed, but there are certainly categories that we would have noticed (aberrant DNA or amino acids, for example)

Personally I think the theory that RNA viruses are a faint shadow of another tree of life is plausible but it is highly debatable.

Agreed. If the RNA precursor model holds up, these end up being more likely as post-host refinements of the tree (e.g., mammalian viruses occurred after mammals arrived).

If indeed there is another tree of life then it would follow it was not as successful as the one we know, at least to our judgment. Saying that to be successful would result in complex life forms is assuming life has a direction a purpose, it does not. The most successful organisms on this planet both in number and in actual bio-mass is bacteria, eukarotes don't even come close to winning that test.

Sure, but it is reasonable in this discussion to define "success" as developoment of higher phyla.

It could very well be that another tree of life is quite successful and has organisms in places our form of life cannot survive or even co-exists along side our own form of life.

This is certainly worthwhile conjecture, but it is certainly conjecture.

[Moontanman]

Sorry, Moon. Didn't meant to do so. But it seems to me that you have to fish or cut bait here. Either there is a biogenesis mechanism that was narrow enough to significantly skew the outcome toward a single "preferred" tree, or there should be evidence of a number (probably a very large number) of different unrelated trees. If you pick the former, you are allowing for the possibility that the tree that surfaced is somehow uniquely likely to diversify. If that is true (since it seems to fit the data), then that unique tree had unique propensity VERY early in the tree, since there is no evidence of other trees.

 

If that is true, the unique tree is "front loaded".

 

Actually no, no single tree is preferred for any reason other than it's ability to adapt and us it's resources efficiently. If eukarotes hadn't come about via the merger of other life forms then Our lovely Earth would be nothing but a planet full of microbes.

 

What is the chance of this happening, hard to say, it might be that if given enough time complex life forms based on some other microbe might have come into existence but it's impossible to know at this point. It is safe to say that no one could have predicted complex life forms from the early microbial earth.

 

The early Earth life was not skewed toward complexity any more than it was skewed toward microbes, it's even possible that most planets never get beyond the free floating metabolisms feeding of each other and the energy provided by the chemical seeps under the ocean and in other places in and on the Earth.

[Turtle]

Bio Chimera Strategy:

 

Reductio ad absurdum - Wikipedia, the free encyclopedia

 

... Reductio ad absurdum is also often used to describe any argument where a conclusion is derived in the belief that everyone (or at least those being argued against) will accept that it is false or absurd. This is a comparatively weak form of reductio, as the decision to reject the premise requires that the conclusion is accepted as being absurd. Although a formal contradiction is by definition absurd (unacceptable), a weak reductio ad absurdum argument can be rejected simply by accepting the purportedly absurd conclusion. Such arguments also risk degenerating into strawman arguments, an informal fallacy caused when an argument or theory is twisted by the opposing side to appear ridiculous. ...

 

In Bi's case, the absurd conclusion we are all expected to reject is that the improbable is impossible. Since however we are alive, it is possible & the argument is moot. :steering: