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A Monkey's Uncle

Discussion of everything related to the Theory of Evolution.

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Postby AstusAleator » Thu Mar 22, 2007 8:54 pm

First I would like to say that I'm enjoying this debate, and by no means am I ever attempting personal attacks. If you feel I am, I apologize.

narrowstaircase wrote:- id like to change your statement above to a more truthful and scientific observation that doesnt imply anything. this sentence:

"For some evolutionary lines, in certain ecological conditions, it has been advantageous to develop larger, more complex nervous systems."

this statement includes some value judgment in the phrase "it has been advantageous" and so doesn't simply state what we see. Where you say “for some evolutionary lines” and “in certain ecological conditions” i can see you imply randomness. And i dont deny randomness (chaos) as a part of our universe. But what if it is “only for those evolutionary lines” and “only in those specific ecological conditions,” that those changes can actually occur?

i would like to change the statement to:

"larger and more complex nervous systems can only develop if certain ecological conditions exist and hense only in some evolutionary lines."

this describes what we see occuring. there is no value judgment involved. It also reiterates what we know about evolution and how interactions drive certain changes. Do you agree with this statement?



While I'm not sure "advantageous" implies a value judgment, I concede that it is unnecessary in the context, as adaptations are by nature advantageous in one manner or another to the organism. The "value" I was using in reference to the term "advantageous" was simply that of fitness, nothing more. I would also substitute the word "develop" with the word "adapt." So my edited statement would be:


"For some evolutionary lines, in certain ecological conditions, adaptation resulted in larger, more complex nervous systems."

The point I'm driving at with this statement is that development of increasingly complex nervous systems is an organisms adaptive response to their environment, not an intentional stage of development towards some ultimate purpose.

narrowstaircase wrote:It also reiterates negetive entropy in that you can only end up with a certain thing if some conditions are met prior. ie. You can only have a multicellular organism if molecules joined to form compounds, compounds joined to form virus like organisms and virus like organisms joined to form single celled organisms in the first place. With out those interactions occuring prior you cannot end up with a multicellular organism.


I would like to point out that you seem to have a very deterministic view of evolution. Perhaps it's just my perception. I see you saying "x can only happen if y," a lot when really we don't have any of those theoretical models 100% figured out yet. There are many different hypothetical versions of how single-celled org.s formed, and several as to how multi-celled org.s came to be.
I know you were just providing a rough example to illustrate a point, but I wanted to point out that perhaps you're stuck in a mode of thinking that doesn't always apply.


narrowstaircase wrote:the new statement also addresses your next point about archeobacteria. they are single celled organisms and hence cant develop a nervous system. they have no need for it because they dont need to function as a whole, their certain ecological condition doesnt allow for that development.

“...and they're still around...” : i dont ever recall saying that purpose implies different associations of matter can't coexist. I dont know where people get this idea from.


While my point about archeobacteria was somewhat flawed, the ultimate message is that if there is purpose behind this accumulation of matter and complexity, and that purpose exists within our DNA or the physical laws of our world (ie is intrinsic in all life) then we would have no remaining examples of primitive life.
I was, of course, extrapolating that your "purpose" is somehow a part of evolution, and thus a part of all living beings. If that's not what it is, then that point is irrelevant.

narrowstaircase wrote:that is akin to me saying, “some wonderful enlightenment could occur tomorrow, wiping out all your doubts and negativity on purpose. Where is your 'non-purpose' then?” i thought we were having a scientific discussion here. Maybe it reflects our views on life. I think they are called feelings... omg i said the f word.


well... I would say my scenario has a little more scientific plausibility (ie meteors, orbit/rotational shifts, etc) but you're right. I was attempting to use the improbable to support my position, which is never a good thing to do.

narrowstaircase wrote:I havent used consciousness in humans as evidence for purpose. This statement confuses me, is it directed to anything specific that ive said or is it a general attack on the idea of purpose? Or are you saying humans should simply stop asking questions about purpose?


By all means, look for meaning and purpose. That's human nature. I'm just saying that in science, there is no context for things such as "purpose" or "meaning." To science you are just an individual Homo sapiens, and your cognitive processes are only significant inasmuch as they affect your and others' fitness, and the environment. Again, I'm not saying that that's all you are, or that there is no purpose to life. Just that within the context of science, philosophy is irrelevant.
I'll go ahead and admit the weakness of that statement right now though: scienctific methods are based on the philosophy of science, so it can probably never be completely free of certain implicit values.

narrowstaircase wrote:so because we observe a continual ordering of matter into larger, more complex, more stable associations throughout the history of Earth we can't extrapolate that to mean there could be an end point of complete order and stability?


exactly. :). No seriously though, that's not necessarily a logical conclusion. It's the kind of logical leap that results in very interesting but very improbable science fiction.
Your ultimate being would be incapable of adaptation, and thus subject to extinction due to changes in the environment or any other number of causes. It's fun to think about things like that, and you could even explore it scientifically if you didn't imply purpose.

narrowstaircase wrote:I havent even explained how this relates to humans but you include your interpretation of this anyway. I've only explained how this trend relates to different associations of matter.


Well, you did mention humans some, but you intentionally didn't go into detail. That's fine... sorry if I jumped ahead.

narrowstaircase wrote:Science is truth.


No, my friend. Science is the never-ending pursuit of truth. Name one thing that science has proven to be absolutely true.
What did the parasitic Candiru fish say when it finally found a host? - - "Urethra!!"
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Postby JDavidE » Thu Mar 22, 2007 9:58 pm

Thanks, Darby. You’ve given me some valid points to work with. Let me just quickly clarify a couple of items.
"...you seem to see the whole biosphere as one organism"

I don’t actually see it that way, Darby, I am just positing a ‘what if’.

"...you seem to be claiming that chimps and humans aren't closely related."

This opens up a whole new can of annelids, but briefly my objection is that we are trying to portray evolution as a periodic table or the ‘begats’ section of the Old Testament (you have already remarked a similar disinclination). Whilst we must indeed have had a common ancestor, regardless of one’s perception of evolution, it is not likely to be recent, in geologic terms. If mutations are cumulative (which they should be) then they must have started out fairly early with either animal. And each cumulative mutation would take them further apart. (I also contend that there just might be a shortcut. This goes on to your sponge and pear tree point (see further down)). We are waving this DNA sequencer tool around (for example) like it was a brand new toy and making all kinds of claims and then counterclaims. I suspect that matching sequences in us and chimps (and several other hominids that we keep pasting into our family album) are just as likely caused by parallel evolution as they are due to a recent ancestor.

"That everything is genetically "the same," with just expression differences, seems to underly your entire idea"

That’s an oversimplification but not totally invalid as to my premise. To modify it so that the argument has some meat would just take too much paper and time for a forum discussion. Let’s go back to your sponge and pear tree example, Darby. The gap from sponge to pear tree is almost certainly too far to make a jump. Even the gap between rose and pear tree is probably too far but at some point, maybe not until right down to the genus level of Pyrus, it might be possible to find the right sequence(s) that declares itself as a pear tree. The problem is, as you rightly pointed out in an earlier response, so what? And to that, I don’t (yet) have an answer.

"... there's always physics (but stay away from the quantum stuff)."

Darby, I can’t even spell quantum. I listen to physics friends expounding theories and I find myself examining their sandwiches to see what condiments they have been sprinkling on them.


"DNA becomes a stabler form of RNA, and proteins become a more chemically active form, both reachable from an RNA starting point. But the system is never DNA in and of itself. "

Total agreement. But it was simpler to just type DNA.


"- the most important process might be the one that produces extra copies of genes."

Now, that’s a very interesting comment.


""Ontogeny recapitulates phylogeny" hasn't been an accepted concept for a very long time."

I thought it was crap the first time I heard it and still think so today. I used it (and withdrew it) because I was trying to think of something to illustrate that if A is true and B is true then both A and B must be true and that was the only thing I could think of at the moment.

"Your examples of animal behavior border on the logic of the Intelligent Design crowd:"

Dear God, no.

"But since it does exist, of course you will see some predatory behaviors specifically aimed at it. (schooling behaviours)"

I have no complaint with any survival strategy. I marvel at each one that unfolds. There is a small rodent-sized animal in Australia (whose name refuses to come to mind) with a strange breeding behaviour. All of the males go into a breeding frenzy and rape with violence as many females as they can and continue to do so until each male suffers a stroke and dies (with a smile on its face). The reason for the strange strategy has now been discovered when the biologists (cruelly) allowed some females to be impregnated by only one male. It seems that the survival percentage of the offspring was significantly greater with females who had multiple matings compared with those who mated (several times) with only the one male. A simple and elegant strategy; just as you would expect from the evolution sieve. But I can’t see any way that the animal can get out of its box. So, apparently, it doesn’t matter if an entire species and maybe an entire phylum can just get obliterated if some small modification occurs. I would like to know why it doesn’t matter. I can almost hear you drawing a breath, Darby, and yes I understand that giving it a name (Evolution) doesn’t give it substance and that it is simply a process of cause and effect. But sentient life surely exerts some influence?

"- what you are suggesting apparently somehow ties to the selfish gene"

If I had it to do over, I would never have begun that sentence by mentioning The Selfish Gene. It plays no part in my argument. I introduced it only to suggest that no theory matters if some other bigger or greater reason is in control. Let me hasten to add before everyone reaches for the Grand Design Argument button that it has nothing to do with that either. Let me illustrate it by taking us entirely away from the subject at hand. The earth experienced a Little Ice Age around 1400. We know it was warmer before then because of inferential evidence. It was in fact warmer then than now (we are still retreating from that cold period). Winemaking was an established industry in England before the Little Ice Age wiped it out. No one has been able to pinpoint the reason for the climate change but there were lots and lots of theories. Galileo was the first to notice sunspots. A record has been kept of their activity ever since. An amateur (I think) astronomer was studying these records and noticed that a period where almost none of these magnetic blemishes appeared on the face of the sun just happened to coincide with the dates of the Little Ice Age. It was too much coincidence to be coincidence. No one knows how sunspot activity can affect our weather but astronomers are certain that they do. So, all of those orthodox theories before sunspots were considered, got trumped by the bigger theory. We now have a very vocal group today warning us about global warming and presenting all of their theories why we should go to great expense to decrease greenhouse gas emissions on their say so. If they haven’t taken sunspots into their equations (we are now in a period of much sunspot activity) then maybe their theories don’t matter either. Can you see my point?
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Postby narrowstaircase » Fri Mar 23, 2007 12:06 am

First I would like to say that I'm enjoying this debate

- i wholeheartedly agree, although i prefer the term discussion. i like your whole previous post. very clear :D


While I'm not sure "advantageous" implies a value judgment, I concede that it is unnecessary in the context, as adaptations are by nature advantageous in one manner or another to the organism. The "value" I was using in reference to the term "advantageous" was simply that of fitness, nothing more. I would also substitute the word "develop" with the word "adapt." So my edited statement would be:


"For some evolutionary lines, in certain ecological conditions, adaptation resulted in larger, more complex nervous systems."

The point I'm driving at with this statement is that development of increasingly complex nervous systems is an organisms adaptive response to their environment, not an intentional stage of development towards some ultimate purpose.


- your new statement is almost exactly the same as my statement "larger and more complex nervous systems can only develop if certain ecological conditions exist and hense only in some evolutionary lines." when you say "an organisms adaptive response to their environment" isnt it clear that those responses can only occur if that environment exists in the first place? (although both the environment and organisms change together, not independantly) this is somewhat a departure in my argument and isnt the evidence im giving for direction in evolution but it does answer the question of why there are different associations of matter on all levels. because certain ecological conditions dont allow for certain developments. you cant get to B if A doesnt exist. you cant develop something if you werent pushed in that direction by your environment. i know that in my example im implying that we already know that B will exist before A has occured but we can extrapolate information. thats how we predict and prediction is substantial.

I would like to point out that you seem to have a very deterministic view of evolution. Perhaps it's just my perception. I see you saying "x can only happen if y," a lot when really we don't have any of those theoretical models 100% figured out yet. There are many different hypothetical versions of how single-celled org.s formed, and several as to how multi-celled org.s came to be.
I know you were just providing a rough example to illustrate a point, but I wanted to point out that perhaps you're stuck in a mode of thinking that doesn't always apply.


- i see what you are saying here and i do understand that there is still alot to be figured out when it comes to ecology. im glad you see that i was illustrating a broad point. i wasn't arguing along the lines of specific organisms adaptations, only when it comes to groupings of matter. the specifics of how multicellular organisms developed is not known for sure but what we do know is that single celled organisms had to have existed beforehand. nervous systems can only be developed if multicellular organism existed beforehand. please tell me where this doesnt apply.


While my point about archeobacteria was somewhat flawed, the ultimate message is that if there is purpose behind this accumulation of matter and complexity, and that purpose exists within our DNA or the physical laws of our world (ie is intrinsic in all life) then we would have no remaining examples of primitive life.
I was, of course, extrapolating that your "purpose" is somehow a part of evolution, and thus a part of all living beings. If that's not what it is, then that point is irrelevant.


- why wouldn't we have any remaining examples of primitive life? i dont understand this premise. the purpose that exists in us also exists in primitive associations of matter below that of life.

I'm just saying that in science, there is no context for things such as "purpose" or "meaning."

- im working on it dude :wink:

To science you are just an individual Homo sapiens, and your cognitive processes are only significant inasmuch as they affect your and others' fitness, and the environment.

- yes, i agree but im attempting to take this understanding a step further. im saying theres purpose in our actions and we can effect the environment toward a meaningfull end.

Again, I'm not saying that that's all you are, or that there is no purpose to life. Just that within the context of science, philosophy is irrelevant.
I'll go ahead and admit the weakness of that statement right now though: scienctific methods are based on the philosophy of science, so it can probably never be completely free of certain implicit values.


- lol ty

exactly. :). No seriously though, that's not necessarily a logical conclusion. It's the kind of logical leap that results in very interesting but very improbable science fiction.
Your ultimate being would be incapable of adaptation, and thus subject to extinction due to changes in the environment or any other number of causes. It's fun to think about things like that, and you could even explore it scientifically if you didn't imply purpose.


- i think this is a significant moment in communicating this idea.!! im excited!

- an ultimate being implies spacial independance but we know this cant be for humans for the reasons you give. the 'ultimate being' im talking about is infact planet Earth that does exist independantly to its surroundings ie. in space. and the energy it needs comes from outside the system (from the sun) and the physical laws it abides by affects its development unidirectionally towards more order and larger associations of matter. do you understand? before i was simply trying to explain that an end point can be seen by extrapolating knowledge and trends we already know. i never said humans are the end point. we are only part of the system. Earth is the system that will reach the end point of total order and stability increasing associations of matter in the process.

Well, you did mention humans some, but you intentionally didn't go into detail. That's fine... sorry if I jumped ahead.

- i might talk about humans and how they fit into this idea later. although it becomes very complicated.

No, my friend. Science is the never-ending pursuit of truth. Name one thing that science has proven to be absolutely true.

- omg you admitted to truth!
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