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Post by Dead Hoosiers on Jul 27, 2005 2:07:40 GMT -4
Sticks ... Also, the development of life doesn't require complete cells to emerge out of nothing. Instead, increasingly complex amino acids are easily assembled (and occur in space too). All that's required is for these amino acids to combine in steadily more complex forms. Why would amino acids combine in "steadily more complex forms" unless they were caused to do so? It's not like they have brains or purpose.
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Post by PeterB on Jul 27, 2005 3:01:32 GMT -4
Why would amino acids combine in "steadily more complex forms" unless they were caused to do so? It's not like they have brains or purpose. Things can happen without brains or purpose. For example, water molecules combine to form snowflakes. The flakes have hexagonal symmetry. Now I'm no biologist or chemist or biochemist, but my understanding is that in the conditions which are theorised to have existed on the Earth early in its history, amino acids would be as likely to combine as water molecules are these days to combine to create snowflakes. I'd recommend a visit to www.talkorigins.org for a primer on theories of the origin of life. Please note, of course, that the origin of life is a separate topic to the evolution of life.
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golfhobo
Venus
DAMN! That woulda gone in the hole IF....
Posts: 86
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Post by golfhobo on Oct 2, 2005 14:48:25 GMT -4
So.... life as we know it is the result of the fact that, given a 50/50 chance, these amino acids didn't combine in steadily LESS complex forms? Or that they didn't combine in steadily more complex forms that followed biological impulses to protect themselves from foreign invasion by other amino acids, and by doing so would create an auto-immune system that prevented the creation of advanced lifeforms? Hey..... just musing!
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Post by PeterB on Oct 3, 2005 23:14:34 GMT -4
Golfhobo said:
It wasn't a single flip of the coin. Each molecular interaction is a flip of the coin. As there are countless trillions of molecules interacting, there are many opportunities for more complex molecules to be created.
This is the essence of natural selection. Very simple rules allow complex systems to develop.
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Post by JayUtah on Oct 5, 2005 10:45:30 GMT -4
Why would amino acids combine in "steadily more complex forms" unless they were caused to do so?
Why would simple oxygen and iron combine to form any of the many complex iron oxides unless they were caused to do so?
It's not like they have brains or purpose.
Rust doesn't need a brain or a purpose either. But it happens.
You don't have to anthropomorphize chemical reactions to understand how they happen or why.
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Al Johnston
"Cheer up!" they said, "It could be worse!" So I did, and it was.
Posts: 1,453
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Post by Al Johnston on Oct 5, 2005 15:12:31 GMT -4
Why would amino acids combine in "steadily more complex forms" unless they were caused to do so? It's not like they have brains or purpose. There's a rather fundamental limit on how they could combine in more simple forms: as there's going to be variation, over time the measure of complexity is constrained to head one way. Stephen Jay Gould explained the concept reasonably well in Life's Grandeur (published in the US as Full House)
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golfhobo
Venus
DAMN! That woulda gone in the hole IF....
Posts: 86
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Post by golfhobo on Oct 8, 2005 10:43:17 GMT -4
It does, however need a catalyst. Isn't the chemical reaction dependent on the input of H2O?
It's been many years since I cared about any of this stuff, but it seems to me that those molecules of Oxygen and Iron can coexist for eons without a "random" combination, unless water is introduced.
Conversely, ONCE water is introduced, they cannot HELP but form iron oxide.
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Post by JayUtah on Oct 10, 2005 17:09:13 GMT -4
It doesn't matter whether a catalyst is needed or whether the reaction is endothermic or any other factor that might prevent a reaction from happening spontaneously. It only matters whether the conditions required for it to occur are met. A house doesn't maliciously burn itself down; it simply undergoes the predictable chemical reaction once the reagents are present and the activation energy has been applied.
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Post by gwiz on Oct 11, 2005 4:12:22 GMT -4
Nice piece from the Guardian on intelligent design. Pages 2 and 3 in particular show the techniques used to promote ID have a lot in common with those of the hoax believers.
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Post by turbonium on Oct 12, 2005 23:50:38 GMT -4
This topic is capable of veering off on many tangents, but at the risk of doing just that, I thought i'd throw another wrench into the works.
I have often wondered about evolution in terms of how it could explain the very non-scientific issue of spirituality. I don't want to make this a religious issue, but for those who believe in the human spirit, or soul, it would make evolution a difficult theory to accept. The physical, biological and chemical processes discussed in evolution theory have no basis for allowing concepts that don't readily seem to exist, or at least are not detectable, in our three-dimensional, five sense world.
I don't want to make too much out of this point, and I'm not a religious type in the least, but it makes for something that I wonder about, at least. I thought about posting this because I've had a a couple of "premonition"- type experiences in my past, that don't readily fit into the world of scientific analysis. So, it makes me definitely aware that there are phenomena that can't be simply put under a microscope or typical analyses.
In the same way, the emotions are another higher level trait that humans have, which are non-existent or more primitive in lower life forms.
Just putting in a little twist - I don't necessarily expect any replies on the topic. But I'd be interested in what others here think about it.....
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Post by PeterB on Oct 13, 2005 1:56:49 GMT -4
Turbonium
If you don't mind, I've started another thread with your post quoted at the start. Perhaps Lunar Orbit might like to tidy that up... *shrug*
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Post by turbonium on Oct 13, 2005 2:23:21 GMT -4
Thx, peter...I guess I should have started a separate thread, but it didn't seem to me like it would be an issue by itself that would spark much interest.... Do you have any thoughts on the matter? If you don't, maybe I was right - it may not be interesting enough to justify it having its own thread! j/k!!
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Post by snakeriverrufus on Oct 15, 2005 23:58:32 GMT -4
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Post by bughead on Jan 9, 2006 16:35:54 GMT -4
One of the ID metaphors I've heard is about the random shaking of Legos until they form the picture on the box. Problem is, chemical equations are not random (join or not join) but statistical: some Legos are more likely to join than others. A problem with this metaphor is that a stack of Legos does not attract other Legos to join the fun. Chemicals do. Feedback loops result. Rust can cause more rust.
Most of "evolution is a theory" that I've run across fails to take into account that feedback loops are not linear systems. As soon as something works massively better (say, surrounding your amino-acid collection with a lipid shell to keep it safe from other amino-acid reactions) the balance of the system is skewed... One reaction may be statistically equal to another in an early system, like in the Miller experiment, but when molecules form that chemically are more active, they take over the reaction environment.
Most people can understand linear systems intuitively, but geometric and logarithmic systems are harder to just grok by looking at them and applying "common sense." The immense depth of time that things have been going on now is also hard to fathom with just a layperson's head full of common sense understandings of common phenomena.
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Post by PeterB on Jan 9, 2006 21:27:52 GMT -4
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