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Chemistry guides evolution, claims theory
NewScientist.com ^ | Jan 20, 2003 | Robert Williams and Joäo José R. Fraústo da Silva

Posted on 01/20/2003 7:01:47 AM PST by forsnax5

That enduring metaphor for the randomness of evolution, a blind watchmaker that works to no pattern or design, is being challenged by two European chemists. They say that the watchmaker may have been blind, but was guided and constrained by the changing chemistry of the environment, with many inevitable results.

The metaphor of the blind watchmaker has been famously championed by Richard Dawkins of the University of Oxford. But Robert Williams, also at Oxford, and Joäo José R. Fraústo da Silva of the Technical University of Lisbon in Portugal say that evolution is not strictly random. They claim Earth's chemistry has forced life to evolve along a predictable progression from single-celled organisms to plants and animals.

Williams and da Silva take as their starting point the earliest life forms that consisted of a single compartment, or vesicle, enclosing the cytoplasm that produced polymers such as RNA, DNA and proteins. That cytoplasm was partly dominated by the reducing chemistry of the primitive oceans and atmosphere from which it formed, and has changed little since, says Williams.

As these primitive cells, or prokaryotes, extracted hydrogen from water they released oxygen, making the environment more oxidising. Ammonia became nitrogen gas, metals were released from their sulphides, and non-metal sulphides became sulphates.

These changes forced the prokaryotes to adapt to use the oxidised elements, and they evolved to harness energy by fixing nitrogen, using oxygen, and developing photosynthesis. But these oxidising elements could also damage the reducing chemistry in the cytoplasm.

For protection, there was just one option: isolate the elements within internal compartments, says Williams. And that gave rise to eukaryotes - single-celled organisms with a nucleus and other organelles.

Quiet revolution

Harold Morowitz, an expert on the thermodynamics of living systems at George Mason University in Fairfax, Virginia, says these ideas are very exciting. "It's part of a quiet paradigm revolution going on in biology, in which the radical randomness of Darwinism is being replaced by a much more scientific law-regulated emergence of life."

According to Williams and da Silva, eukaryotes also had to evolve a way to communicate between their various organelles. The surrounding raw materials dictated how this could be done. Calcium ions would have routinely leaked into cells, precipitating DNA by binding to it. So cells responded by pumping the ions out again.

Eukaryotes evolved to use this calcium flow to send messages across internal and external membranes. Similarly, sodium ions formerly expelled as poisonous became the basis of communication in nerve cells.

Life continued to react to Earth's oxidised environment. Hydrogen peroxide gave rise to lignin - an oxygen-rich polymer that is the chief constituent of wood. And eukaryotes used copper oxidised from copper sulphides to cross-link proteins such as collagen and chitin, which help hold nerve and muscle cells in place. Such evolution of materials suitable for multicellular structures paved the way for plants and animals.

Chicken or egg

Not everyone is convinced. Evolutionary biologist David Deamer of the University of California, Santa Cruz, says the claim that evolution followed an inevitable progression should be qualified: "The inevitability depends on the origin of life and oxygenic photosynthesis."

He agrees that life arose in vesicles, but says that oxidative chemistry cannot explain everything from prokaryotes to humans.

Williams admits their theory has limitations. For instance, he agrees that Dawkins's argument is correct in that chance events drive the development of species. But he does not believe random events drive evolution overall. "Whatever life throws away will become the thing that forces the next step in its development."

However, David Krakauer, an evolutionary theorist at the Santa Fe Institute in New Mexico, says Williams and da Silva have simply listed the chemical processes that coincided with each evolutionary transition, which does not prove that the chemistry caused the transitions. But Williams says that the environmental changes had to come first, because they occur faster than changes in biological systems.


TOPICS: News/Current Events; US: California; US: New Mexico; US: Virginia
KEYWORDS: biology; chemistry; creationism; crevolist; evolution; life; science
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To: Havoc
Nobody who studies earth or natural history is going to give you rock-solid experiments and theories. There simply isn't the data, nor replicability.

I'm not fully versed in the literature of evolution, but I think it's well-accepted that the primeval atmosphere was anoxic and that free oxygen developed via photosynthesis. CO2 has likewise varied by at least an order of magnitude and is controlled in the long run by tectonism, volcanism and rock weathering rates.

As for extinctions, atmospheric chemistry changes fairly significantly between glacial and interglacial periods without extinguishing life or anything of the sort. This is known from direct measurement of air bubbles trapped in polar ice. Furthermore life has survived numerous cataclysmic impacts and disruptions.

61 posted on 01/20/2003 9:29:58 PM PST by Monti Cello
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To: PatrickHenry
Evolution of the Eye. [according to Darwin]

"To suppose that the eye with all its inimitable contrivances for adjusting the focus to different distances, for admitting different amounts of light, and for the correction of spherical and chromatic aberration, could have been formed by natural selection, seems, I freely confess, absurd in the highest degree.

Yet reason tells me, that if numerous gradations from a perfect and complex eye to one very imperfect and simple, each grade being useful to its possessor, can be shown to exist; if further, the eye does vary ever so slightly, and the variations be inherited, which is certainly the case; and if any variation or modification in the organ be ever useful to an animal under changing conditions of life, then the difficulty of believing that a perfect and complex eye could be formed by natural selection, though insuperable by our imagination, can hardly be considered real. How a nerve comes to be sensitive to light, hardly concerns us more than how life itself first originated; but I may remark that several facts make me suspect that any sensitive nerve may be rendered sensitive to light, and likewise to those coarser vibrations of the air which produce sound."

The impossibility of the evolution of the eye (according to Michael Behe):

What is needed to make a light sensitive spot? What happens when a photon of light impinges on the retina?

When a photon first hits the retina, it interacts with a small organic molecule called II-cis-retinal. The shape of retinal is rather bent, but when retinal interacts with the photon, it straightens out, isomerizing into trans-retinal. This is the signal that sets in motion a whole cascade of events resulting in vision. When retinal changes shape, it forces a change in the shape of the protein rhodopsin, which is bound to it. Now part of the transducin complex dissociates and interacts with a protein called phosphodiesterase, When that happens, the phosphodiesterase acquires the ability chemically to cut a small organic molecule called cyclic-GMP, turning it into 5'-GMP. There is a lot of cyclic-GMP in the cell, and some of it sticks to another protein called an ion channel. Normally the ion channel allows sodium ions into the cell. When the concentration of cyclic-GMP decreases because of the action of the phosphodiesterase, however, the cyclic-GMP bound to the ion channel eventually falls off, causing a change in shape that shuts the channel. As a result, sodium ions can no longer enter the cell, the concentration of sodium in the cell decreases, and the voltage accross the cell membrane changes. That in turn causes a wave of electrical polarization to be sent down the optic nerve to the brain. And when interpreted by the brain, that is vision. So this is what modern science has discovered about how Darwin's 'simple' light sensitive spot functions.
From: Michael Behe, 'Design at the Foundation of Life".

Now which one of the two is science and which one is not?????

62 posted on 01/20/2003 11:05:17 PM PST by gore3000
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To: PatrickHenry
No, it's only by your contorted reading of what I posted. I can't debate about phantasms which exist only in your mind.

Obviously Ahban does not understand evolution. Evolution is rapid only when evolutionists say so. At other times it can be slow, slower, slowest and virtually non-existent. Only an evolutionist is qualified to determine what the proper speed is under the given circumstances (and what is needed as proof of evolution).

63 posted on 01/20/2003 11:12:07 PM PST by gore3000
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To: Havoc
if you flood the planet and hold the heads of all dogs under water, they will not suddenly adapt and learn to breath water.

Great point! Interestingly, while evolutionists claim that environment causes genetic changes, they completely reject Lamarckism (that the environment is the cause of the changes in species).

64 posted on 01/20/2003 11:16:30 PM PST by gore3000
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To: Monti Cello
I think it's well-accepted that the primeval atmosphere was anoxic and that free oxygen developed via photosynthesis.

Plants cannot live without oxygen.

65 posted on 01/20/2003 11:28:28 PM PST by gore3000
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To: gore3000
Evolution is a hopeless dichotomy . . . a dead branch of science - - - a zit on the face of science // humanity ! ! !
66 posted on 01/21/2003 2:55:54 AM PST by f.Christian (Orcs of the world: Take note and beware.)
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To: gore3000
Plants cannot live without oxygen.

Shhh - don't tell these guys....

67 posted on 01/21/2003 6:47:25 AM PST by general_re (Save the whales. Feed the hungry. Free the mallocs.)
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To: Monti Cello
but I think it's well-accepted that the primeval atmosphere was anoxic and that free oxygen developed via photosynthesis.

Ie this is the theory the evolutionists like today.

As for extinctions, atmospheric chemistry changes fairly significantly between glacial and interglacial periods without extinguishing life or anything of the sort. This is known from direct measurement of air bubbles trapped in polar ice. Furthermore life has survived numerous cataclysmic impacts and disruptions.

Air bubles in ice prove there are air bubbles in ice. What they prove beyond that is subjective. And life has survived some pretty terrible things. There's just no evidence that life has been through noxious chemical changes in the atmosphere, witnessed GEEs or evolved as result of such change rather than perishing. Moreover, Science can only guess if the planet was ever without an atmosphere or that it was ever other than what it is today with variations on c14. In short, what you are stating as fact is merely theory.

I would throw in a good question about how wooley mammoths could be flash frozen in mid stride such that even the contents of freshly chewed food in the stomache and mouth are undigested and intact. Might also ask how a "polar" climate animal (as evolutionists define them) can eat buttercups, green grass and the like in far northern Siberia. Really puts a nasty wrinkle in things. Buttercups don't grow on frozen tundra. Nor evidently do Mammoths. And if there are tropical forests a mile under ice, where'd all the water come from necessary to bury a land mass that large under a mile of ice. Hmmm. Good questions all; but, evolution can't explain them as a whole. Oh well. looking forward to the entertainment to come.

68 posted on 01/21/2003 9:30:29 AM PST by Havoc ((Evolution is a theory, Creationism is God's word, ID is science, Sanka is coffee))
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To: gore3000
Is rather silly that they should both argue for and against depending on the situation. Sounds like another group I can think of.
69 posted on 01/21/2003 9:32:05 AM PST by Havoc ((Evolution is a theory, Creationism is God's word, ID is science, Sanka is coffee))
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To: Havoc
Just calling evolution a theory is an overstatement . . . only an idea // mood // feeling - - - an ideology // perverse oddity ! ! !


70 posted on 01/21/2003 10:12:13 AM PST by f.Christian (Orcs of the world: Take note and beware.)
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To: f.Christian
Conjecture masquarading as science might be more appropos - I agree.
71 posted on 01/21/2003 12:04:31 PM PST by Havoc ((Evolution is a theory, Creationism is God's word, ID is science, Sanka is coffee))
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To: Havoc
What is your explanation for the existence of intact woolly mammoths?
72 posted on 01/21/2003 2:33:44 PM PST by Monti Cello
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To: Monti Cello
You mean intact wooley mammoths frozen in mid stride. I was quite precise about this. I believe the numbers involved the decline in body temperature of the beast by -175 degrees near instantly. No pummice or ash in the ice, BTW - which is all important. It can't be explained by a slow creeping ice age. Can't be explained by a slow cooling associated with a meteor hit or megavalcano blast.
How do you get a volume of water high enough to completely cover and encase a Beast the size of a Mammoth that also happens to be -175 degrees F or colder? Keep in mind that the beast I'm particularly thinking of is 13 feet high.
The rear legs were slightly twisted and pushed forward while the front legs were spread to the sides and forward.
The long bone of one of the rear legs was compressed along it's length and shattered into 12 places without showing damage to outer soft tissue. It's mouth, nostrils and eyes were all wide open. And cause of death deemed as asphixia.
Not only was the contents of his stomache undigested (which happens within an hour after death due to the caustic nature of stomach acids, he had grasses and been pods lodged in his mouth that were frozen so quickly that according to the report, the imprint of it's mollers could be seen in the grasses. There were over 40 identified edibles in the beasts stomach ranging from pine needles, grasses and fruits to buttercups.. The majority of these things are things that do not grow as previously mentioned in such an intemperate climate as that of Siberia. Oh, one more factoid for you, The beast froze so fast that it's cells didn't burst. I'm sure you aren't a pet coroner; but, it requires sudden complete freezing at -150 F or better to achieve this. I'm just giving you a smattering of the things involved. You tell me what happened. I already know. A volcano can't do it. A meteor can't put that volume of water high enough to freeze it, nor can it create enough water mass to account for the depth, nor can we account for a meteor of that size impacting this planet without utterly destroying it or leaving no trace of itself.
I might add that this is not the only one. Mammoths have been found in this upright state flash frozen all over siberia and across the northern reaches of the old soviet bloc countries and Alaska. Not just mammoths; but, Rhinos, and other animals as well. Rhinos don't much get people's attention. Mammoths on the other hand do.
</p>
73 posted on 01/21/2003 3:31:49 PM PST by Havoc ((Evolution is a theory, Creationism is God's word, ID is science, Sanka is coffee))
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To: Havoc
Fascinating. How do you explain it?
74 posted on 01/21/2003 3:45:56 PM PST by Monti Cello
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To: PatrickHenry
Like the time when I spent days saying that Uranus was the 8th planet ...

You were counting the asteroid belt. Yeah, that's the ticket...

75 posted on 01/21/2003 3:47:33 PM PST by Dan Day
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To: Dan Day
You were counting the asteroid belt. Yeah, that's the ticket...

Right! Used to be the 8th planet. Of course. I must have been reading from a very old tour guide. Gotta clean out my office one of these days.

76 posted on 01/21/2003 4:15:39 PM PST by PatrickHenry (Bring back the Articles of Confederation!)
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To: Monti Cello
First you need a flood. Not just any flood, you have to lower the water temperature to -175 degrees F or colder.
You can't do that Planetside without destroying the atmosphere and even then, the sun would intervene. Thus the water has to jet into the upper atmosphere. But again, it has to be enough water to cover once tropical forests to an average depth of 1900 feet. I'd note, factually, that these are not petrified - they are frozen. Drilling expedition after expedition have turned up vegitation, cores of frozen trees, grasses, pine needles, leaves, you name it from depths of 1600 feet and down. The water came from somewhere, and all that land used to be above water.
There is no evidence it was imported - a volume of water large enough to make a meteor large enough to shatter this planet, not just impact it and make it go "ouch" So either it was once sealed below the continents, or you have to find some really creative way of explaining where we inherited a planetoid volume of water from without completely destroying the planet. Based on what we know about what's burried in the north, you are talking about lowering the water level planet wide by 1900 feet minimum and accounting for that volume of water. And that is a small planet. Not a meteor.

No matter how one approaches the question, it boils down to a flood. But not your usual type of flood. The evidence of it lies on the ocean floor yet today and circles the earth where the crust fractured. The salt deposites on either side of the fractures have not grown, they've stayed constant in size, meaning it's not an ongoing or growing deposit. Scientists objectively agree that the continents were once joined. When they split off from each other, there had to be a force that created that and explaines where the residue went. It's no coincidence that the layers upon layers of Rock ice that cover the northern expanses of Alaska, old Soviet Russia across to China and the north and south poles are filled with particulate matter - soil, grasses, etc that actually discolor the ice to a sulfury yellow/brown color. Same is true with regard to the icepacks that cover the mammoths and other animals found in a flash frozen state. This is a worldwide catostrophic event that happened so fast that cells don't burst, nostrils are flaired, mouths open, eyes open, and animals are suspended in mid stride. The atmosphere is left intact (run that by physicists with a global killer scenario, they'll laugh you off the planet).

77 posted on 01/21/2003 4:27:09 PM PST by Havoc ((Evolution is a theory, Creationism is God's word, ID is science, Sanka is coffee))
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To: general_re
Shhh - don't tell these guys....

They can live longer without oxygen than insects so one can kill the insects by depriving them of oxygen without killing the plants in a greenhouse. Not what we are talking about at all is it?

78 posted on 01/21/2003 4:35:19 PM PST by gore3000
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To: gore3000
[Behe writes:] When a photon first hits the retina, it interacts with [snip] So this is what modern science has discovered about how Darwin's 'simple' light sensitive spot functions.

Now which one of the two is science and which one is not?????

Darwin's is, since he lays out a specific hypothesis which can be examined and tested (and if found wanting, falsified).

Behe, on the other hand, describes the activity of a *modern* eye (note he starts out talking about a "retina"), then at the end pulls a bait-and-switch and implies that such things are necessary for a primitive "light sensitive spot".

Just like your dishonesty on another thread, that's like trying to "prove" the impossibility of the Wright Brothers making a working airplane in their garage by waving the high-tech plans for a Stealth Bomber -- and thus pretending to have proven that the entire aviation industry was too improbable to believe.

That's not science, that's dishonest lawyering.

Nice try.

79 posted on 01/21/2003 4:49:41 PM PST by Dan Day
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To: Monti Cello
Fascinating. How do you explain it?

The Flash Frozen Mammoth

The stories of the flash frozen mammoths get more detailed and more dramatic with every retelling. The most famous find (until the very recent one) was the "Beresovka Mammoth," found largely intact in Russia in 1901. There wasn't a lot of excitement about it until the mid-50's, when Immanuel Velikovsky picked up on it.

The Velikovsky Version

Immanuel Velikovsky became notorious in 1950 when he published Worlds In Collision. Velikovsky believed in literal interpretations of ancient texts that described bizarre occurrences, and he devised theories of catastrophic events to explain them.

He followed with another, lesser known book in 1955 called Earth In Upheaval. In this book, he explained the demise of the mammoths, and it's recounted here.

From the link:

The evidence for these catastrophes had to be largely geological. Velikovsky was fascinated by the profusion of mammoth bones and tusks and even frozen bodies that had been found in Siberia and Alaska. There were three key points as far as he was concerned: one, that the existing tundra seemed totally inadequate to provide enough plant material for huge animals like mammoths to subsist on. The second point, related to the first, was that their stomachs contained the remains of plants that couldn't have grown so far north. And three, the frozen mammoths seemed to have been flash frozen. To Velikovsky, the only possible explanation was that these animals had been living in a much more temperate clime, which had suddenly - and I mean suddenly - turned ice-cold.

And here's how he explained this strange turn of events:

"Let us assume, as a working hypothesis, that under the impact of a force or the influence of an agent - and the earth does not travel in an empty universe - the axis of the earth shifted or tilted. At that moment an earthquake would make the globe shudder... The shifting of the axis would also change the climate of every place, leaving corals in Newfoundland and elephants in Alaska..." So some unidentified cosmic object disturbed the Earth and one of the myriad effects was the death and preservation of mammoths in ice. Later he argues that the famous Beresovka mammoth, found with clots of blood in its chest and unswallowed grass clenched between its teeth, is a testimony to the violence and suddenness of whatever cataclysmic event caused the extinction of its species.

So how well do the arguments stand up under scrutiny? Not very well. First, were the mammoths quick-frozen? No. Almost all of the frozen specimens found so far have been rotten, and in some cases, mutilated by scavengers before freezing. Even the ground around the aforementioned Beresovka mammoth, as well as the mammoth's flesh, stunk of decay. Had freezing been instantaneous, no decay would have occurred. That is why we have fridges, isn't it?

They died, not by freezing, but by asphyxiation. Evidence for that is the discovery of vessels still filled with coagulated blood and the little-known fact that the Beresovka mammoth died with an erection.

Second, the stomach contents. Turns out both the Mamontova and Beresovka mammoths had eaten a variety of plants, including grasses, sedges and other tundra plants, as well as the cones and twigs of northern trees. Overall these plants represent a flora that would exist in slightly warmer and wetter conditions than exist in Siberia today, but such conditions are well within the climatic variability of the past.

There are some other points that Velikovsky seems to have overlooked, one of which is that the mammoths were obviously adapted to Siberian cold. They had long hair, a woolly undercoat and a thick layer of subcutaneous fat.

Finally the numbers of frozen mammoths don't support the idea of a catastrophe. It's been estimated that there might have been about 50,000 mammoths living in the Arctic, while something like forty have been found frozen. Hardly the signs of a cataclysmic event.

As well, only mammoths and woolly rhinoceroses have been found frozen. Why only them and no other animals? Presumably because they were heavy and unable, if they fell, to extricate themselves from either marshy ground or snow-filled gullies. Elephants, and presumably mammoths before them, need to be balanced so precisely on their pillar-like legs that they can't cross a ditch any wider than their stride length.

Most of the evidence on both sides of this argument comes from the 1950s and earlier, but you shouldn't take that as evidence that this controversy is dead. In fact there is a 303 page book published in 1997 called The Extinction of the Mammoth, by Charles Ginenthal that revisits the controversy. Mr. Ginenthal appears to be Velikovsky supporter, and the publication of this book shows that Velikovsky's influence on scientific discourse has not waned.


80 posted on 01/21/2003 5:36:47 PM PST by forsnax5
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