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Author
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Topic: Wheels of Life
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Mike Gene
Member
Member # 149
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posted 26. June 2003 01:03
Rex,
Thanks for the picture. But a question remains – will it work? I’m still having a hard time visualizing how the tissue in the wheel receives sufficient blood. And as John noted, there seems to be a problem associated with circulation in a moving wheel because of centripetal force pushing the blood to the edges of the wheel.
Then there is the issue of how you generate the movement. That is, the rotary motion not only seems to pose serious problem for the blood supply and connective tissue bands (again, as John noted), but also for the musculature. What is the motor?
Keep in mind that if we are to replace limbs with wheels, two other features are needed. First, you need a steering mechanism. Here, you better position the wheels far enough out so when they are turned, they don’t rub up against the side of the animal. But then we have to worry that the bone-axle is strong enough so that it doesn’t break.
And we need a braking mechanism also. Something that can stop the biowheel quickly without damaging the tissue due to the associated friction . If a wheel is spinning at 400 rpm, is dense regular connective tissue strong enough to put the breaks on without ripping?
Keep in mind that wheels are also associated with rolling friction. This would mean that typical mammalian epidermal tissue would probably be insufficient as tread. And a quick brake would be associated with a skid, something that could easily damage epidermal tissue. You might also need some form of coolant mechanism to deal with the heat generated in your rotational cavity.
The bottom line is that your picture reminds me of some of the pictures inventors used to draw when first trying to invent flight. They looked good on paper, but many didn’t work.
There is also the other question concerning why a designer would puts wheels on an animal instead of limbs. In many ways, limbs appear to be superior to wheels.
First, a wheel seems much more prone to injury. Since the entire epidermal tread is exposed to the terrain, more surface area is put at risk. An animal that runs across a terrain contacts the ground only where the paws momentarily hit the in ground. A simple survey of animal tracks shows that most of the ground is not contacted as the animal moves along. But the tracks of a wheeled animal would show that the animal continuously contacts the ground.
And what if a wheeled animal damages one of its wheels? If my dog hurts her paw, she can still hop along on three legs, getting some decent motility while allowing the injured paw of heal. To mimic this, we’d need a mechanism to sufficiently lift the wheel off the ground. So we’re continuously adding features to your picture.
Secondly, limbs are clearly more versatile. If an animal is walking through the woods, it can easily step over fallen trees. An animal with wheels would find this a difficult obstacle. Wheels would more easily get stuck in the mud. And what if a wheeled animal is turned on its side?
Animals with limbs can jump. They can dig. They can climb. They can use their limbs to fight. Scratch. Groom. Grab. Wheeled animals seem to be stuck rolling about.
[ 26. June 2003, 01:42: Message edited by: Mike Gene ]
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Mike Gene
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Member # 149
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posted 26. June 2003 01:29
Charlie,
As I said, if the cell turned out to be a bag of soup, I would most likely not be seriously contemplating design. One of the main reasons I suspect design is because the cell has turned out to be far more sophisticated than a bag of soup. Yes, there are people who see no difference between a bag of soup and a factory. Some IDists would credit the soup to a designer. And non-teleologists think a factory is no more cause for an ID suspicion than a bag of soup. Me? I respond to the data.
As far as the flagella are concerned, I’m simply highlighting the fact that bacterial motility does not require wheels (the 3 possibilties can be addressed another time, as each one opens a tangential, but intriguing, topic). Ultimately, the non-teleologist explains the existence of such wheels according to happenstance. Perhaps I cannot rule this out. But then, neither do I find it a compelling explanation.
Finally, my argument is not premised on anything being the “best engineering solution.”
BTW, I’m hitting up against my self-imposed 50 Rule. I’ll offer one more round of replies.
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charlie d.
Member
Member # 159
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posted 26. June 2003 07:15
quote:
As I said, if the cell turned out to be a bag of soup, I would most likely not be seriously contemplating design. One of the main reasons I suspect design is because the cell has turned out to be far more sophisticated than a bag of soup. Yes, there are people who see no difference between a bag of soup and a factory. Some IDists would credit the soup to a designer. And non-teleologists think a factory is no more cause for an ID suspicion than a bag of soup. Me? I respond to the data.
It seems to me that more than to the data, you are responding to a certain aesthetics, that goes with the scientific and technological development of the time. In fact, so do all of us, even mainstream scientists. But the only way to judge a technology we cannot replicate ourselves is "a complex-looking thing that does something", which would apply to cells even if they looked like bags of soup.
I can almost hear the "Unlocking the Mistery of Life III - The Designer Strikes Back" voice-over:
"Someday, human scientists might be able to use "bag of soup"-like lattices to perform the most sophisticated tasks: drink a special soup, and get your appendectomy performed from within! Pour a cup of soup on you computer, and it will fix it!
Today, of course, we are not able to replicate the highly advanced bag-of-soup nanotechnology, but a small band of ID scientists, the same who met 50 years ago in a beach house in California (but are steadily growing in number!) are beginning to understand it, and we all can watch it work and marvel at the pervasiveness of ultrasophisticated Intelligent Design in Life.". ![[Wink]](wink.gif)
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Jack Foster
Member
Member # 79
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posted 26. June 2003 11:34
Hi RBH:
quote:
I conclude that in those cases where a problem is intractable to forward and inverse modeling but where an EA produces a satisficing solution to an adaptive problem, the designer could not in principle have intended that solution to occur!
I recognize that the designer is not aware of the exact solution to a particular problem in advance. But he is aware of the problems, whether man-made or natural, and he is attempting to access a phase space where solutions to the problems are available. For man-made evolutionary systems, that phase space is accessed by the design of the gene to phene map. I don't believe there could be a way to achieve an evolutionary system without that design.
So is this really design or non-design (chance)? Well, it is a combination. The designer uses stochastics as another tool in the chest. He may be surprised on occassion by some result, even as he continues to hone his craft. I won't quibble over the word "intention".
I'm going to be traveling for the next six weeks or so, so this will be my last post for a time. I'll conclude with a quote from Tom Ray:
quote:
"The AL researcher does not view the computer as a tool for modeling organic life. Rather the computer is seen as an environment that can be inhabited by non-carbon based life. The work of AL then is to seed this environment with life forms, and to cultivate the system so that it may support ever richer digital life forms."
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John Bracht
Member
Member # 5
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posted 26. June 2003 12:21
RBH,
You're confusing intention with certainty. If I intend to do something, it is ALWAYS possible that I might fail. I might fail to drive to the store this morning and buy some toothpaste--perhaps I get into an accident and end up in the hospital instead. Intentions are far different from certainty in a conclusion or outcome, or "success" in some sense of the term.
So your comment that the Lenski et al simulation was not intentional is itself vacuous. You're just confusing intention with success--an odd conflation of terms, if you ask me.
I repeat: the Lenski simulation WAS an intentional project, TRYING to evolve EQU-capable organisms. The experimenters knew very well what their intentions were and they set up the program to meet those intentions. Sure, it's possible they might have failed (but then there wouldn't be a Nature paper, would there?). The whole process was highly teleological and just because they might have failed makes not one iota of difference.
It's worthwhile pointing out that every experiment, while outcome is unknown, is an intentional effort to test some hypothesis. There is a result we're intentionally looking for, and whether we find it or not will tell us about the nature of the real world (hopefully). Once again, the fact that we don't know with certainty the outcome makes no difference in the fact that the whole process was entirely goal-oriented, intentional, and design-driven.
Finally, you spiral off into all this stuff about how I've somehow conceeded that this simulation really does evolve IC systems, that such systems can evolve without viable precursors; I'd ask you to PLEASE NOT PUT WORDS IN MY MOUTH. Honestly, I think the claim is so ludicrous that there is no need to even bother responding. My point here is to correct your mistaken ideas about intentionality, not to make meta-claims linking the Lenski et al simulation to the evolution of IC, biological systems, or anything of the sort. Furthermore, I've already made my veiws known on these other matters, and you know as well as I do that your assertions (of what I think) are completely contrary to my own views. So again--please, RBH, do me the courtesy of not putting words in my mouth. And if you do, please at least try to make the words you put in my mouth agree with what I think.
Thanks,
John
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zygotecowboy
Member
Member # 220
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posted 26. June 2003 12:45
quote:
My post did not imply that the human designed turboshaft was not complex, just that it is not as complex as the flagellum.
Nelson, thank you for responding. Perhaps this is a misunderstanding of the term "complexity", and this wouldn't be a surprise given that there are two very different definitions of complexity within the dialogue between IDists and ID critics. Kolmogorov complexity refers to the information required to describe the object in question. Dembskian complexity, on the other hand, says nothing about the current state of the object; it relies solely on the probability that the object originated via chance and natural processes. Which notion of complexity are you referring to here? Did you actually do the calculations, or is this just a hunch? And if you did the calculations, can you please post them here?
If you mean Dembskian complexity, then you’re suggesting that it’s more likely that the human designed turboshaft arose by chance and necessity than the bacterial flagellum. This seems like an odd claim to me, given the overwhelming evidence that the human designed turboshaft was designed by humans.
zc
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yersinia
Member
Member # 324
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posted 26. June 2003 13:03
John Bracht writes,
quote:
It's worthwhile pointing out that every experiment, while outcome is unknown, is an intentional effort to test some hypothesis. There is a result we're intentionally looking for, and whether we find it or not will tell us about the nature of the real world (hopefully). Once again, the fact that we don't know with certainty the outcome makes no difference in the fact that the whole process was entirely goal-oriented, intentional, and design-driven.
Therefore, weather is designed because weather simulations are designed, and gravity is designed because Galileo designed the cannonball-dropping experiments?
Look, here's the point of an experiment. You set up something with certain conditions, and see what will happen. You then conclude that, where similar conditions happen to exist in nature, that similar things will occur.
Selection, and selectable intermediates with different functions, do appear to exist in nature. Saying that an experiment is invalid because the experimenter put in natural selection is like saying a climate simulation is invalid because the experimenter put in the sun.
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John Bracht
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Member # 5
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posted 26. June 2003 13:13
Yersinia,
What, exactly, has your argument got to do with my discussion with RBH? Could you please spell out the logical connections, because I fail to see them.
Thanks,
John
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RBH
Member
Member # 380
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posted 26. June 2003 13:52
John wrote quote:
It's worthwhile pointing out that every experiment, while outcome is unknown, is an intentional effort to test some hypothesis. There is a result we're intentionally looking for, and whether we find it or not will tell us about the nature of the real world (hopefully). Once again, the fact that we don't know with certainty the outcome makes no difference in the fact that the whole process was entirely goal-oriented, intentional, and design-driven.
And my point is that saying that the experimenters intentionally ran an experiment tells us precisely nothing about whether intentionality is necessary to the outcome of the experiment. Within the experimental 'world' of the Avida there is no intentionality. This conflation of levels - the level of the design of the experiment and the level of processes within the experimental 'world' - confuses the issue. The question at issue is whether intentionality is necessary to account for the phenomena we see - allegedly IC structures - within the biological world. Appealing to intentionality in the construction of a model world in which to test that hypothesis is irrelevant to the question of whether intentionality characterizes the processes occurring within the model.
My conclusion about your 'concession' is derived directly from your sentence quote:
Rather, a specific goal was intended by the designers of the program, who set up the conditions such that the goal (evolution of organisms capable of carrying out the EQU function) was met. That's intentionality if I ever saw it.
The fact that the "goal" - a program that performed EQU - was achieved in a simulation that modeled evolutionary processes demonstrates that evolutionary processes can indeed evolve arguably IC structures under the circumstances modeled in the simulation. And I might note that I did not claim that you conceded that could occur in a context without viable precursors. Quite obviously, precursors are necessary - the no-precursor control condition established that.
The conditions of the experiment did not include "intention" in the processes of the experimental world except insofar as the simulation employed a fitness function that induced a fitness landscape that was not flat across all logic operations except EQU. There was no overseeing intentional agent within the simulation that guided, directed, or otherwise intervened in the processes of the programs as they evolved. The fitness function induced a fitness landscape with a non-uniform topography. And that models the real world - real fitness landscapes are not flat.
RBH
[ 26. June 2003, 13:54: Message edited by: RBH ]
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yersinia
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Member # 324
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posted 26. June 2003 14:32
John,
RBH pretty much said it just now. Apologies for being oblique.
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John Bracht
Member
Member # 5
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posted 26. June 2003 14:56
RBH,
quote:
And my point is that saying that the experimenters intentionally ran an experiment tells us precisely nothing about whether intentionality is necessary to the outcome of the experiment.
But you'd agree, wouldn't you, that without intentionality, the organism capable of performing EQU would never have existed? In other words, setting up the experiment, and equipping it in such a way that the EQU result is rewarded (and other intermediates are selected for) is absolutely essential to the (successful) outcome of the experiment. No intentionality, no experiment, no outcome. So I think it's a little deceptive to claim that intentionality is unnecesary for the outcome of the experiment when 1. the experimenters set up a computer-evolvable system, and 2. the experimenters set up the evolvable system such that it had precisely the parameters to allow and reward the desired outcome. If you have (1) without (2), you'll never get EQU-capable organisms. Without (1), you'll never get a computer simulation of anything at all.
Intentionality makes all the difference to the outcome, in my mind.
John
P.S. both you and Yersinia keep wanting to apply this to biology and say that intentionality makes no difference there. I see that as a totally separate issue. Let's settle the question of whether intentionality is important in the simulation first, and we can argue about applications later. Is the simulation intentionality-driven or not?
[ 26. June 2003, 14:58: Message edited by: John Bracht ]
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charlie d.
Member
Member # 159
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posted 26. June 2003 16:13
quote:
both you and Yersinia keep wanting to apply this to biology and say that intentionality makes no difference there. I see that as a totally separate issue. Let's settle the question of whether intentionality is important in the simulation first, and we can argue about applications later. Is the simulation intentionality-driven or not?
Of course the simulation was run intentionally, but so what? Intention was not included in the experimental parameters. As yersinia pointed out, Galileo's experiments with cannonballs were also performed intentionally. No Galileo, no intentionality, no experiment, no outcome (cannonballs falling with uniform acceleration).
The question for you is, therefore:
do cannonballs intentionally fall with uniform acceleration?
[ 26. June 2003, 16:13: Message edited by: charlie d. ]
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Argon
Member
Member # 276
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posted 26. June 2003 17:36
John Bracht writes:
quote:
Intentionality makes all the difference to the outcome, in my mind.
![[Smile]](smile.gif) The road to Hell is paved with good intentions. I wonder where the road paved with bad intentions goes...
See if this helps:
Let us presume that the fundamental physical constants of the universe were "intentionally" pre-configured to permit the emergence of life. That makes the outcomes -- i.e. EQU emergence in AVIDA and IC systems in biology -- metaphysically identical. Can we move on now?
[ 26. June 2003, 17:36: Message edited by: Argon ]
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Argon
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Member # 276
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posted 26. June 2003 17:48
Mike Gene writes:
quote:
I’m still having a hard time visualizing how the tissue in the wheel receives sufficient blood. And as John noted, there seems to be a problem associated with circulation in a moving wheel because of centripetal force pushing the blood to the edges of the wheel.
Consider a wheel in which the rim is bony, dead, and physically separated (at least after "wheel maturation"). Then the only part that requires circulation (and lubrication) is the axle. Ratcheting or "gripping and releasing" mechanisms rotate the rim (Or maybe a jet of pressurized fluid). As the bony wheel wears (probably not too fast in aqueous environments), another could mature to take its place.
Or...
Consider a wheel in which the rim is composed of living, but hard, slow growing tissue. This rim is physically unconnected to the axle but is fed by nutrient-rich lubricating fluid produced by the axle (or perhaps the rim is fed by symbiotic organisms -- maybe the rim itself is a separate organism).
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John Bracht
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Member # 5
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posted 26. June 2003 18:15
Charlie, Aargon,
I think you're missing the point, and prematurely trying to apply a very specific point about a computer simulation to the real world, or biology.
RBH was arguing that the results of the Lenski et al. simulation were not intentional. I'm arguing they were--very intentional. That's it. I'm not trying to make an argument about the universe as we know it, the emergence of life, the emergence of IC systems, etc.
Can you all understand that?
RBH: do you agree or disagree with my point as it stands: about the simulation?
John
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