| From: Olly | 12/11/99
14:31:06 |
| Subject: Did we evolve from clay... part II | post id:
6879 |
Sorry I am posting this again, but the original thread has just developed (for better or for worse) into a full fledged evolution debate. Anyway the book I was reading was "The Blind Watchmaker" (which I'm sure would convert any creationist if they bothered to read it) by Richard Dawkins. On page 150 he talks about clay, and more specifically about Cairn's Smith's book "Seven clue to the origin of life". He talks about how crystals can replicate and can aquire imperfections into their structure being the first "replicators". If you supersaturate a solution with an inorganic compound, you can "seed" it with a small crystal of the compound and voi-la! you have millions of the crystals. Anyway I couldn't be stuffed re-typing about 4 pages of this book. But as we know, that crystals can replicate, multiplicate, and obtain imperfections, we are still missing a "power" element to there being any evolution. The book talks about how perhaps there are many streams with clay beds on a primeval world and that maybe there is a particular type of clay or crystal that improves its own chance of being deposited and hence damming up a river. A small pool forms as the river does a detour around this dam. This small pool contains this particular "damming" crystal, and all along the length of the river there may be many puddles of this kind with this type of crystal. During the dry season these pools dry up and the particular dust particles of the "damming" crystal can be blown into other river systems and start the whole process again. It's not really a life cycle but I just find it fascinating.... Could this have been a cycle that started the life cycle?? Anyone have any opinions on it? | |
| From: Kent - yes, ignorant me again | 12/11/99
15:19:02 |
| Subject: re: Did we evolve from clay... part II | post id:
6887 |
| Well, you have reproduction...
that's step 1. But for something to be considered "living" (I think I
recall from Yr11Bio) it has to be able to gain nutrition (maybe the use of
inorganic compounds covers this). This will be OK until the pre-organism
moves (or is blown) into an environment where it needs to actually search
for food and avoid harm. In such an environment, the pre-organism will
need to concentrate nutrients within itself - this requires some mechanism
such as a cell membrane with semi-permeable, osmosis/diffusion-defying
qualities. I think it is somewhere around here that you may come across
the problem creationists describe as "irreducable complexity";ie, that
certain components need to be simultaenously present for the whole
organism to survive. I think most people agree that for this to succeed you'd need millions of years and exactly the right conditions at each phase of these pre-organisms' development. In other words, a helluva lot of luck! The question is: "Is this just too flukey to be believeable?" I personally have more problems with the Archeopteryx - the bird "missing link". It is difficult to see how a useless pre-wing would be of any use until it had developed to a certain extent - in fact it would be more likely to get in the way which would naturally select that species right outta there! Don't answer to this people. Olly wants your comments on the clay thang | |
| From: steve(primus) | 12/11/99
15:27:07 |
| Subject: re: Did we evolve from clay... part II | post id:
6888 |
| In other words,
a helluva lot of luck! The question is: "Is this just too flukey to be believeable?" What are your chances of winning Lotto? About 4.5 million to one. What are the chances of someone winning Lotto? about 100%. Why? Although there are many changes to organisms, most are not beneficial, but the odd one is. It is the Lotto winners in evolution that pass their genes on to others. Given the huge amount of time involved and the numbers of individuals and the numbers of mutations, Lotto winners pop up regularly. | |
| From: Kirsten | 12/11/99
15:51:46 |
| Subject: re: Did we evolve from clay... part II | post id:
6894 |
| And our lotto losers don't die as
a result and fail to have offspring (evolution's 'lotto' losers
do). Kirsten. | |
| From: MikeE | 12/11/99
16:03:10 |
| Subject: re: Did we evolve from clay... part II | post id:
6896 |
| Evolution looks to be a slow
process (especially as opposed to creation -- a week's work?). It's probably not unreasonable to assume that other molecules may have displayed self-organising behaviour long before complex amino acids did. But this doesn't have to mean they were "alive". | |
| From: steve(primus) | 12/11/99
16:05:25 |
| Subject: re: Did we evolve from clay... part II | post id:
6897 |
| so? I used lotto as an analogy
for chance things happening. Beneficial genes get passed on, if there is
no change, the organism keeps going as before - and there are plenty of
examples of those: the tuatara and the coelacanth for
instance. | |
| From: MikeE | 12/11/99
16:09:07 |
| Subject: re: Did we evolve from clay... part II | post id:
6899 |
| Supposedly for the universe to be
balanced at the current rate of expansion is a 10^-60 chance or so, but as
others have said, if this is the throw of the dice we have, why not accept
it, instead of concerning ourselves with the other dire possibilities
which are not observed (us not being here, etc), as things clearly DO
exist the way they ARE. | |
| From: Kirsten | 12/11/99
16:11:49 |
| Subject: re: Did we evolve from clay... part II | post id:
6900 |
Steve, Sorry, I was actually agreeing with you, just pointing out that in evolutionary terms we don't get the losers of the lotto hanging around to whinge about it, which is why it looks like there are so many winners. Kirsten. | |
| From: steve(primus) | 12/11/99
16:16:00 |
| Subject: re: Did we evolve from clay... part II | post id:
6904 |
| fair enough Kirsten, I
misunderstood you. | |
| From: Matt | 12/11/99
17:37:16 |
| Subject: re: Did we evolve from clay... part II | post id:
6953 |
| I just wanted to suggest that
Creation and Gensis were not written as a science textbook - only to show
who and why created everything! | |
| From: Olly | 13/11/99
11:50:09 |
| Subject: re: Did we evolve from clay... part II | post id:
7053 |
| Kent, I don't think the clay or crystal particles need to worry about nutrients and a cell membrane. They can pick up the inorganic ions in the river and grow. The energy they get for survival would be the kinetic flow of the river and the blowing of the wind. It would seem that crystals/clays that have the best ability to deposit themselves would thrive and overpopulate the worlds river systems. However I can think of two other lineages that the crystals could develop. Perhaps one particular crystal has developed a deformity whereby it is made more lighter and fluffier when it is dried out. So therefore when the wind blows it, it can travel to further river systems, and more of it can be spread. Perhaps there is another type of crystal which can break apart more easily (therefore it multiplies itself more readily). With this scenario you have three different types of crystal which could be competing against each other. What makes that NOT a form of life?? It is still a MONUMENTAL leap from crystals to single cell bacteria though..... but I still somehow think that life originated from inorganic crystals rather than the popular "primevil soup" theory. | |
| From: Olly | 13/11/99
11:51:22 |
| Subject: re: Did we evolve from clay... part II | post id:
7054 |
| Kent, I don't think the clay or crystal particles need to worry about nutrients and a cell membrane. They can pick up the inorganic ions in the river and grow. The energy they get for survival would be the kinetic flow of the river and the blowing of the wind. It would seem that crystals/clays that have the best ability to deposit themselves would thrive and overpopulate the worlds river systems. However I can think of two other lineages that the crystals could develop. Perhaps one particular crystal has developed a deformity whereby it is made more lighter and fluffier when it is dried out. So therefore when the wind blows it, it can travel to further river systems, and more of it can be spread. Perhaps there is another type of crystal which can break apart more easily (therefore it multiplies itself more readily). With this scenario you have three different types of crystal which could be competing against each other. What makes that NOT a form of life?? It is still a MONUMENTAL leap from crystals to single cell bacteria though..... but I still somehow think that life originated from inorganic crystals rather than the popular "primevil soup" theory. | |
| From: Olly | 13/11/99
11:52:21 |
| Subject: re: Did we evolve from clay... part II | post id:
7055 |
| Kent, I don't think the clay or crystal particles need to worry about nutrients and a cell membrane. They can pick up the inorganic ions in the river and grow. The energy they get for survival would be the kinetic flow of the river and the blowing of the wind. It would seem that crystals/clays that have the best ability to deposit themselves would thrive and overpopulate the worlds river systems. However I can think of two other lineages that the crystals could develop. Perhaps one particular crystal has developed a deformity whereby it is made more lighter and fluffier when it is dried out. So therefore when the wind blows it, it can travel to further river systems, and more of it can be spread. Perhaps there is another type of crystal which can break apart more easily (therefore it multiplies itself more readily). With this scenario you have three different types of crystal which could be competing against each other. What makes that NOT a form of life?? It is still a MONUMENTAL leap from crystals to single cell bacteria though..... but I still somehow think that life originated from inorganic crystals rather than the popular "primevil soup" theory. | |
| From: Grantley | 13/11/99
12:18:03 |
| Subject: re: Did we evolve from clay... part II | post id:
7058 |
| Life produces inorganic material,
so, it stands to reason that at some stage organic material was produced
by what could be described as inorganic material. I think the most
probable is a "primoval soup" scenerio with complex chemicals building up
over long periods of time with complex and random (chaotic?) chemical
reactions. | |
| From: Dr. Ed G (Avatar) | 14/11/99
6:19:28 |
| Subject: re: Did we evolve from clay... part II | post id:
7161 |
| It's important to note that
organic molecules have a truly astounding flexibility in terms of their
structural/chemical forms... specifically their polymeric forms. This is
the key aspect of the way carbon bonds to other molecules, and virtually
no other element has the chemical repertoire that carbon has. And so,
while it is important not to rule out anything, per se, it is extremely
difficult to see how any basis for life (which fundamentally must be
flexible and adaptive) would not involve carbon in a big
way. | |
| From: Kent | 18/11/99
15:06:31 |
| Subject: re: Did we evolve from clay... part II | post id:
8453 |
| Olly, I don't think anyone adequately explained how a pre-organism could progress to a stage where it could survive in an environment where resources were scarce. Sure a crystal might be blown into a river or pool where there were plenty of "nutrients" but at some point, these crystals (or whatever they evolved into) would have to survive scarcity. This is the point where a cell membrane would be needed and a mechanism to increase the concentration of nutrients relative to outside the membrane (which as I pointed out, defies the usual osmotic/diffusion processes). It is incredibly flukey for an organism to evolve this fully-fledged system at the same time it is removed to a scarce environment. I do think certain components/abilities need to be present simultaenously as the crystal (or whatever) is blown out of the nutrient rich environment. And I can't see this happening. | |
| From: Tim St. Clair | 22/11/99
0:19:45 |
| Subject: re: Did we evolve from clay... part II | post id:
9138 |
| I dunno, I always read that
section of Dawkins' book as an analogy, rather than than a part of the
actual "life" evolution process. That is, he was trying to explain how DNA
and its associated molecules arose out of the primordial "chemical soup"
which has already been mentioned - anything which has the tendency to
replicate itself will do so (and anything which doesn't,
won't). And the chemical soup experiments have been done; if you mix up methane, ammonia, carbon monoxide, water - all simple compounds present on the primordial earth (and some of Jupiter's moons, these days, intriguingly - 2010, anyone...?) - heat them, zap them with electicity, expose them to UV light, etc. you find that various more complicated chemicals have formed, simple amino acids, aromatic rings like DNA bases, interesting stuff like that. The relevance is that the clay particles could then act as a catalyst for further reactions, like polymerisations, by electrostatically binding to the "complicated" monomer units and lining them up regularly and close enough to react with each other. Hey presto, proteins and nucleic acids... So maybe we did evolve from clay - but only indirectly.... (By the way, I seem to recall from 6th Form College the defining characteristics of life fitting the acronym MR GRENS - being Movement, Respiration, Growth, Reproduction, Energy(?), Nutrition and S...? Anyone help me out?) Remember, Olly, there's lots in the "The Selfish Gene" which is wildly fanciful - once you get to the bit on "memes", you'll see what I mean. (I heard Dawkins himself was a little embarrassed about that part, later). Even Charles Darwin later retracted a chunk of "The Origin of Species" (the part about Lamarckian selection, if anyone's interested). The point is that these books are valuable not because they tell us things, but because they make us think about things. (And that goes for the Bible/ Torah/ Koran etc. - amazing insights into human psychology, those ones...) Flame at will, guys, Tim | |