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Author
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Topic: Updating Paley's watch: High technology and the circadian rhythm.
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nobody
Member
Member # 145
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posted 25. June 2003 12:44
In his Wheels of Life thread Mike Gene comments on the nanotechnology of life:
quote:
In a sense, cells do have “cog wheels,” only they are more sophisticated than Paley’s watch.
That got me to wondering what obviously designed object Paley would have chosen today for his example, if he were alive. He certainly would have been shocked at the current level of human technology, which many of us take for granted.
He might have selected the Space Shuttle which, although it is very impressive by human standards, does not match the design of life. Or perhaps he would have stayed in the timekeeper mode and chosen one of our more advanced time pieces to prove his point. Either way I bet he would have been very surprised to learn that God had designed miniature clocks right into life itself!
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Light Sets the Molecular Controls of Circadian Rhythm
Light sets the circadian rhythm by eliminating a key protein needed for the molecular mechanism of the body's clock, according to scientists in the March 22 Science. The findings, from fruit fly studies, may help explain light's effect on the daily cycle that influences sleep, mental alertness, pain sensitivity and temperature and hormone levels.
http://www.rockefeller.edu/pubinfo/light.nr.html
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Paley might have never even thought about the idea of an internal human clock, since jet lag was unknown during his lifetime:
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First Human Circadian Rhythm Gene Identified
http://www.hhmi.org/news/ptacek2.html
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An interesting point about living clocks is made in this article:
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In a third study—this time in mice—researchers at the University of Wisconsin Medical School in Madison showed that the Mop3 gene is important in regulating the cycling of the mouse clock. Christopher A. Bradfield and colleagues hypothesized that the MOP3 protein is the partner of the CLOCK protein, and they confirmed its circadian role by knocking the gene out in mice: Animals without Mop3 had no circadian rhythms.
"This is the first case of a single mutation that completely abolishes the circadian clock," says Bradfield, who collaborated with Takahashi's laboratory on the study. The findings were published in a December issue of Cell.
http://gnn.tigr.org/articles/05_01/Clock.shtml
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Paley would have been greatly impressed by an atomic clock, and also by circadian rhythm. The atomic clock we have. Figuring out all the details about how biological clocks work is something we are still working on.
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Evan
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Member # 164
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posted 25. June 2003 17:52
Circadian rhythms may be something that could be shown to be designed (if in fact the procedures for establishing design were to become empirically practical), but nobody also claims that it was God who did the designing.
I'm curious as to the grounds upon which Nobody might make that claim?
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Rex Kerr
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Member # 632
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posted 25. June 2003 20:02
Circadian rhythms are one area where evolutionary co-option seems at, perhaps, its most obvious. in Drosophila a cryptochrome protein dCRY acts as a photosensor, much like in plants, and regulates a downstream protein TIM, which goes on to regulate other other components in the circadian rhythm pathway.
In mice, however, CRY appears to have taken over the function of TIM entirely, leading the the bizarre scenario of having a light-sensing protein expressed deep inside an organism where no light reaches, functioning as a regulator of a pathway instead of a light sensor.
If the circadian rhythm pathway was designed, it seems to have subsequently evolved, or the designer who created the Drosophila and mammalian variants on the pathway had an impish sense of humor.
Added in edit: Oops, forgot the reference to the review article for those who can access Nature. Panda et al., "Circadian rhythms from flies to human", Nature 417:329 (2002).
[ 25. June 2003, 20:04: Message edited by: Rex Kerr ]
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Joy Busey
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Member # 610
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posted 25. June 2003 20:08
quote:
Evan said: Circadian rhythms may be something that could be shown to be designed (if in fact the procedures for establishing design were to become empirically practical), but nobody also claims that it was God who did the designing.
Hello, Evan. I have read Nobody’s post three times now, and I can’t seem to find where s/he claims “God” did the designing. In fact, all I see is the relating of recent biological research on circadian clocks to Paley’s argument from design.
Paley’s argument was of course theistic, and we also recognize Nobody’s theistic alignment. I am just wondering why you would waste a post trying to make a point that is essentially lost by virtue of its pointlessness. I mean, you have not refuted anything in the links offered, nor have you established that the biological usefulness of circadian clocks cannot infer design.
Whether or not anyone’s defined deity is responsible for biological clockworks (“works” relating back to Mike Gene’s thread, noted atop Nobody’s post) is not something that can be established or falsified here in this forum or in any laboratory where these designs are being quantified through research. If design is evident in the existence of such clockworks, all we can surmise is that their existence is so specific to the constraints governing life here on this particular planet that if the same sort of clockworks evolved on a planet with much different cycles (rhythms), those would likely be different from those we see here.
Since you say that these clockworks “may” infer design, does that mean you recognize that RM-NS Darwinism cannot readily explain them? I am not sure if it could or not, though there is certainly nothing random about the fine-tuned parameters - constraints - on this planet, which is thus far the only one where we know for sure that life exists (and/or evolved).
Life’s fine-tuning to the rhythms of the planet isn’t accidental, it’s a reflection of life’s physical adaptation to the rhythms of this planet. Which intuitively seems just what we ought to expect, doesn’t it? Why would we expect to find life forms here with metabolic rhythms and cycles attuned to the orbit, rotation, bio-niche competitions and seasonal progressions of Uranus?
quote:
I'm curious as to the grounds upon which Nobody might make that claim?
Again, Nobody did not make the claim explicitly, but merely by inference in citing Paley’s argument. Since we all know Paley made the argument, and that it’s actually pretty good (and getting better the more specificity we find in biological design), why shouldn’t the connection be made?
You can no more demonstrate empirically that “God” didn’t design this specificity than you can demonstrate that RM-NS did design this specificity. It’s not like a circadian clock operating on Uranus time would easily survive here in Earth time, and even if you found one that did you’d have to explain why it operates on Uranus time. If Earth life arose and existed/evolved here on Earth, then of course its internal clocks will be set to Earth time. That’s a design specificity we could expect to see even if we were to find DNA-programmed, carbon-based life to be ubiquitous throughout the universe. It would operate on local time if it developed in local time.
That says nothing at all about the identity or nature of the designer of life. It just says something about local conditions, to which life is specifically adapted.
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Evan
Member
Member # 164
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posted 25. June 2003 23:26
Nobody wrote, "Either way I bet he would have been very surprised to learn that God had designed miniature clocks right into life itself!"
That was the line to which I was referring.
My post, which I admit was short and not particularly according to the rules of ISCID, was implicitly referring to two long-standing issues here:
1) Can design actually be empirically detected? and if so, by what procedures? and
2) If it can, what do the results of design detection tell us about the designer(s) that is based on empirical evidence as opposed to faith.
Nobody's statement seemed to imply a connection between what he sees as designed (an as-of-yet unestablished point) and who he sees as the designer. My question was meant to ask if there were grounds, and by that I meant empirical grounds, for thinking that God, as opposed to some other type of designing agent(s), was the cause.
[ 25. June 2003, 23:28: Message edited by: Evan ]
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Joy Busey
Member
Member # 610
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posted 26. June 2003 11:04
quote:
Evan said: My post, which I admit was short and not particularly according to the rules of ISCID, was implicitly referring to two long-standing issues here:
1) Can design actually be empirically detected? and if so, by what procedures? and
2) If it can, what do the results of design detection tell us about the designer(s) that is based on empirical evidence as opposed to faith.
Thanks for clarifying, Evan. To your (1), I’d have to say design is detectable primarily upon our consensus definition of what qualifies as design. Unless there’s concensus, it’s just a matter of opinion. If there is concensus, then the criteria for detection could be formalized and systems could be subjected to rather simple yes/no eliminations for classification.
On (2), I am not convinced that quantification of design criteria would necessarily tell us anything about designer(s). All we would know about is the relative simplicity or sophistication of the designs. For example, I have a friend who teaches CAD design at a local college. One of his favorite projects for advanced students is to design a container in which an egg can be placed, to be dropped from a second floor walkway onto asphalt as part of the end-term grade - the egg is supposed to survive the drop, and it can’t be hard boiled. There are a few limitations on size and materials, but mostly it’s the students who come up with the designs.
Some of the designs are elaborate, some are quite simple. Surprisingly many of them actually serve the stated purpose of keeping the egg intact. Contemplating what I would design, and then observing the egg drop and seeing the student designs is very educational. Some opt for a box full of various kinds of shock absorbing insulation. Some opt for a series of foam and rubber balls. Some weight their conveyance so as to ensure the egg hits on the long axis (this turns out to be important), some attach parachutes for the same effect. Some use cardboard, some use string and hot glue. Of the “pass” designs - those that do protect the egg - it’s not that difficult to tell from materials that the system is designed. But if the materials were of similar bio-origin as the egg (or its chicken mother), it would not be all that easy.
My favorite looks like a large feathered shuttlecock, like a badminton birdie. The egg is suspended just above the weighted half-ball inside a rigid open pyramid (wooden structure) with a corrugated cardboard “fan.” Were the struts made of bones and the weighted shock absorber of pliant cartilage, it could pass for something natural if you didn’t know any better. In fact, quite a few of these students of design turn to nature for their ideas of design. If you think about it just a bit, it could be recognized that we humans draw some of our best designs from nature all around!
And if we weren’t worried about ideological constraints, that would inform us of something important to this conundrum.
quote:
Nobody's statement seemed to imply a connection between what he sees as designed (an as-of-yet unestablished point) and who he sees as the designer. My question was meant to ask if there were grounds, and by that I meant empirical grounds, for thinking that God, as opposed to some other type of designing agent(s), was the cause.
I personally do not believe it likely that we will ever be able to identify a specific designer of nature’s vast array of excellent designs, precisely because adaptive change here on planet Earth is part of the process. And should the designer(s) of volitional life itself have front-loaded that adaptability into the expression programming, we could not expect to find tiny nanofairies waving at us when we look through our microscopes.
While that in no way precludes our ability to quantify design in nature, it doesn’t help us establish who did the designing. Even if a designer were perfectly natural by definition, s/he/it could exist in more than 3 spatial dimensions, which would make s/he/it “super”natural here in just 3. We cannot hope to precisely quantify that which we cannot perceive, observe or measure. All we can do is strongly suspect the existence of more, and if more is strongly suspected, we cannot rule out forms of volitional life existent in more.
...so I don’t think identifying designer(s) is all that important. Identifying designs is good enough, FAPP. What individuals believe about designer(s) isn’t something science need concern itself about.
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Nel
Member
Member # 614
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posted 27. June 2003 21:59
Rex writes:
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In mice, however, CRY appears to have taken over the function of TIM entirely, leading the the bizarre scenario of having a light-sensing protein expressed deep inside an organism where no light reaches, functioning as a regulator of a pathway instead of a light sensor.
Actually, there is evidence that CRY in mice does act as a sensor of ambient light.
quote:
Cryptochromes function in both light entrainment of circadian rhythms and in a peripheral circadian clock mechanism in Drosophila. Mice have two closely related cryptochrome genes (mCry1 and mCry2). To further understand the roles of mammalian cryptochromes, we bred mice to carry all possible combinations of wild-type and cryptochrome knockout alleles, and tested these mice for free-running and entrained circadian rhythmicity. We find that a single wild-type copy of mCry1, but not mCry2, is sufficient for free running circadian rhythmicity; however, these mice show markedly variable free-running periods. Two wild-type copies of either mCry1 or mCry2 are sufficient to establish a stable free-running clock. A subset of mCry1-/mCry-; mCry2-/mCry2- mice have a diurnal activity preference, suggesting that cryptochromes function in light-dependent behavioral masking. We also analyzed mice lacking both cryptochromes and carrying the homozygous rd retinal degeneration mutation. These mice have markedly depressed behavioral photoresponses in light-dark conditions, despite having an anatomically intact retinohypothalamic tract and normal expression of melanopsin. These results suggest that, similar to insect cryptochromes, mammalian cryptochromes function pleiotropically in both circadian rhythm generation and in photic entrainment and behavioral responses.
J Neurogenet. 2002 Jul-Sep;16(3):181-203
On a related note, it looks like the clock of cyanobacteria may be irreducibly complex in that it requries kaiABC:
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Inactivation of any single kai gene abolished these rhythms and reduced kaiBC-promoter activity.
Science. 1998 Sep 4;281(5382):1519-23.
[ 17. February 2006, 18:52: Message edited by: Nel ]
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