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Life's lucky 'kick start'
BBC News ^ | October 13, 2003 | Dr David Whitehouse

Posted on 10/16/2003 7:33:43 AM PDT by AntiGuv

The Cambrian Explosion - when life suddenly and rapidly flourished some 550 million years ago - may have an explanation in the reaction of primitive life to some big event.

The explosion is one of the most significant yet least understood periods in the history of life on Earth.

New research suggests it may have occurred because of a complex interaction between components of the biosphere after they had been disturbed by, for example, the break-up of a super-continent or an asteroid impact.

Scientists say the life explosion might just have easily occurred two billion years earlier - or not at all.

Dramatic events

All modern forms of life have their origin in the sudden diversification of organisms that occurred at the end of the so-called Cryptozoic Eon.

Scientists have struggled to explain what might have happened in the previous few hundred million years to trigger such a burst of life.

Certainly, it was a period of history that witnessed the assembly and break-up of two super continents and at least two major glaciation events. Atmospheric oxygen levels were also on the rise.

But what actually caused the Cambrian Explosion is unknown.

Writing in the journal Geophysical Research Letters, Dr Werner von Bloh and colleagues, from the Potsdam Institute for Climate Impact Research, present a new analysis of happened.

They suggest that "feedback" in the biosphere caused it to jump from one stable state without complex life to one that allowed complicated life to proliferate.

"We believe that there was a change in the environment - a slow cooling of the system - that caused positive feedback that allowed the conditions for complex life," Dr von Bloh told BBC News Online.

Self regulation

Using a computer model of the ancient Earth, the researchers considered three components of the biosphere, the zone of life.

These were single-celled life with and without a nucleus, and multicellular life. Each of these three groups have different environmental tolerances outside which they cannot thrive.

The computer model showed there were two zones of stability for the Earth - with or without higher lifeforms - and that 542 million years ago the planet flipped from one to the other.

What caused the flip is not clear. It might have been a continental break-up, or even an asteroid impact.

There is some indication that the Moon suffered a sudden increase in impacts about the same time as the Cambrian Explosion. If so, then the Earth would have been affected as well.

This latest analysis also provides some support for the Gaia hypothesis - the idea that the biosphere somehow acts as a self-sustaining and regulating whole that opposes any changes that would destroy life on Earth.

Intelligent beings

Dr von Blow says that after the Cambrian Explosion there has been a stabilisation of temperature up to the present, and that the biosphere is not playing a passive role.

He also adds that there is an intriguing implication from his research which suggests that had the conditions been only slightly different, the Cambrian Explosion could have occurred two billion years earlier.

An early explosion would have meant that by now the Earth could have developed far more advanced intelligent creatures than humans.

Alternatively it could still be inhabited by nothing more complex than bacteria.

Dr von Bloh says that it will be of great interest when we find other Earth-like worlds circling other stars to see if they have had their own Cambrian explosions yet.

The timing of such events has implications for the search for intelligent life in space, he says.


TOPICS: Culture/Society; News/Current Events
KEYWORDS: biology; crevolist; evolution; origins
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To: Modernman
I have no problems believing in God and, at the same time, accepting the theory of evolution. I have no need to prove the existence of God to anyone- I accept it on faith. I do have a need to see evidence before I accept a scientific theory, and I haven't seen anything with better evidence to explain how we got here than the theory of evolution.

The problem that most theologians grapple with is that if evolution were true, there would have been no reason for Jesus to die on the cross.

A foundation of Scripture is the plan of salvation that Jesus completed on the cross with His sacrificial death and His subsequent resurrection. Thus conquering the death that Adam made as a Free-Will choice in Eden. Adam's choice to forfiet his inheritance to Satan, brought about original sin, as well as the curse on our universe.

To make it short, evolution blows all of these scriptural doctrines out of the park, leaving an empty husk of lies and half-truths. This is why Biblically literate believers completely reject the idea that God used evolution to bring us to this point. It contradicts the whole of the Old and New Testament writings.

281 posted on 10/18/2003 6:23:54 PM PDT by bondserv
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To: whattajoke
But that's predicting outcomes of pressures upon populations and how it will affect lifespans and/or densities. When I was doing my thesis, we were careful to discern the difference between, "species x will become species y" and "species x will become a differently selected species x."

Which of course is absolute garbage and has been proven to be so. The problem which population genetics cannot solve for evolution is that mutations occur in individuals, not in groups. What this means is that any mutation must spread throughout the population before it can become the building block for further steps in the transformation of one species into another. The smallest mutation is a single bit pair mutation and such cannot accomplish what is required for it to spread throughout a species according to the very laws formulated by evolutionists - a large beneficial effect.

To create a new organ would take millions of new base pair mutations. A new organ would be useless until it was complete. Thus the claim that mutations could create something as necessary to get from bacteria to humans as a single new organ is utterly impossible. Add to this that such intermediate steps to the creation of a new organ have never been observed, that thousands and/or millions of mutations each being a bit more beneficial at every step is impossible and what you have is evolution being disproven by its very own rules.

282 posted on 10/18/2003 6:43:39 PM PDT by gore3000 ("To say dogs, mice, and humans are all products of slime plus time is a mystery religion.")
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To: gore3000
And again you attack the heart of the matter. How can this be missed (denied)?
283 posted on 10/18/2003 6:54:44 PM PDT by bondserv
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To: gore3000
Quick Cure for Some Genetic Diseases Planned    10/17/2003
Certain forms of muscular dystrophy and cystic fibrosis may soon be curable with a pill, says New Scientist.  The pill helps the protein-building machinery read through the “stop code” in a defective gene so that an essential protein can be made.  Experimental tests with the drug, named PTC124, may begin on humans next year.
If it works, this will be wonderful news for many who suffer from these diseases.  The mechanism of the cure points out the specificity of the genetic code.  When the stop code is correctly located, the ribosome knows when the protein ends, and all is well.  If a premature stop code has been inserted in the gene by a mutation, protein construction is aborted, and the incomplete polypeptide is destined for destruction.  The new drug has a way to latch onto the stop code and prevent it from being interpreted as such.  It’s like putting a cover over a stop sign, or commenting out an extraneous EXIT directive in a computer script.
    Notice how damaging single mutations like this can be (see Oct. 1 headline on pleiotropic effects).  Sufferers of these genetic diseases are not surviving as the fittest.  They are not evolving into something more complex.  Complex life is sustainable only because a sophisticated factory of machines work against equilibrium to produce interacting, functional networks (see Sep. 29 headline).
    Throughout the uncountable zillions of copies of genes made daily throughout the living world, most mistakes are caught and corrected.  Occasionally, one slips through.  The results can be devastating.  Why mistakes are allowed to exist is a question for philosophers and theologians, but it is exciting to see that scientists, discerning the inner workings of the genetic code, are finding ways to bypass the errors and provide new hope for millions affected by them.
    Actually, every human is suffering under the mutational load accumulated through thousands of years of inheritance.  It is very probable that the first humans were much more fit (i.e., possessing error-free genomes).  Only presumption believes evolution is improving our fitness.  The evidence indicates we are devolving, because many harmful mutations are known, but there are no unequivocal examples of helpful mutations.
    By exercising good design science, we can apply our intelligence to help repair what errors our genetic mechanisms occasionally let slip, but we should be not proud: compared to the built-in manufacturing and proofreading processes in the cell, our techniques amount to little more than sticking a finger in a dike.
Link
284 posted on 10/18/2003 7:06:32 PM PDT by bondserv
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To: bondserv
This is a very interesting drug which apparently is able to take advantage of the specificity of our genetic code to create a drug which deals with a specific mutation. One of the problems with drugs in general is that they are not specific enough. That is why they have side effects. They may make up for a lack in one place but because they act on the whole body they may be deleterious in other areas than the one intended.

The human body has numerous mechanisms to insure that the right materials are produced in the right places even though theoretically any protein could be produced in any cell (since the DNA is the same in all cells with a couple of significant exceptions). By learning to direct drugs more specifically we will be able to get rid of side effects and make them more effective and perhaps make them usable for an entire lifetime. This new drug seems to be a more specific variation of one that was used previously with some side effects and was not as effective as the article in New Scientist explains.

285 posted on 10/18/2003 8:15:28 PM PDT by gore3000 ("To say dogs, mice, and humans are all products of slime plus time is a mystery religion.")
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1720

Placemarker

286 posted on 10/19/2003 9:49:06 AM PDT by PatrickHenry
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To: PatrickHenry
Seems you are going around 'placemarkering' right after my posts? What's the purpose? Do you have anything else to do with your life than waiting for me to post?
287 posted on 10/19/2003 11:05:32 AM PDT by gore3000 ("To say dogs, mice, and humans are all products of slime plus time is a mystery religion.")
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To: PatrickHenry
Thank you for your reply!

A lot of the professional disagreements in this business are about just such issues [new body plan v new species].

I'd be astonished to see a creature with a truly novel Hox cluster classified as merely a new species - but I've been astonished by such things before...

288 posted on 10/19/2003 9:24:13 PM PDT by Alamo-Girl
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To: whattajoke
Thank you so much for your reply and for sharing your point of view!

AG, I'd wager you could write up a pretty cool essay parsing your beliefs from the book of Revelation, combining your idea for what the post-Christ's-return environment would look like, think about the new environmental pressures, and go from there. Another world-wide flood? Increased temperatures? Increased volcanism?

The new heaven and new earth described in Revelation 21 need not obey any of the physical laws of this universe, including space/time, arrow of time, dimensionality, etc. God promises to make all things new.

However, the millenium of Christ's rule on earth described in Revelation 20 - though not restricted by the physical laws - will evidently comport with enough of them that there will continue an earth and nations in fulfillment of the prophesy.

289 posted on 10/19/2003 9:36:38 PM PDT by Alamo-Girl
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To: JethroHathAWay
Thank you for sharing your musings on vampires. Indeed, if there ever were a creature which could instantly transform its own body at will (not like a caterpillar/butterfly) - it would have to be called a new body plan.
290 posted on 10/19/2003 9:40:32 PM PDT by Alamo-Girl
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To: Hank Rearden
So, what horribly-mutated branch of this Tree of Life resulted in the creation of government parasites?

Dunno. Is there still time to prune?

291 posted on 10/19/2003 9:47:09 PM PDT by null and void
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To: bondserv
The problem that most theologians grapple with is that if evolution were true, there would have been no reason for Jesus to die on the cross.

I don't see that.

Does the path God and our free will chose to get where we are matter more than where we arrived?

292 posted on 10/19/2003 9:52:10 PM PDT by null and void
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To: Right Wing Professor
I finally got a chance to read the article! I'll reread it again tomorrow, but it appears he retraces what you summarized. However, as with the other articles I've read he also notes the stability of the Hox clusters (emphasis and reformatting mine):

Analysis of a complete homeobox gene repertoire: Implications for the evolution of diversity

Although this result is not necessarily surprising, it has a number of important evolutionary implications:

(i) An increased number of genes may provide greater complexity but does not automatically imply greater diversity of the repertoire.

(ii) The mammalian lineage appears to have elaborated, by multiple gene duplications, a basic homeodomain repertoire that was shared with ancestors to arthropods and nematodes. Even although the mammalian and fly genomes are yet incomplete, they attest to more frequent gene duplications than in C. elegans. Clearly, there are only few examples of homeodomain duplicates in C. elegans, and it is unclear whether there were recent gene duplications. Nevertheless, the basic repertoire in mammals, and presumably the gene regulatory control mechanisms encoded by it, evolved fundamentally similarly to their invertebrate counterparts.

(iii) The extent of diversity in homeodomain repertoires appears to be comparable for nematodes, arthropods, and mammals. Thus, the repertoires in different clades did not expand appreciably in variability during evolution. There are two possible explanations for this constancy: either the homeodomain possesses only limited “mutability” (presumably for structural reasons) or the time elapsed did not allow yet for greater divergence. The latter possibility is unlikely as some sequences exist that have evolved independently (such as for example, Drosophila bicoid and some genes unique to C. elegans).

(iv) The evolutionary progression, at least for homeobox genes, more likely involved numerous duplications of terminal branches rather than invention of novelty. With respect to the hypotheses set forth at the start of this study, this favors model 2 (Fig. 1B) as the evolutionary scenario.


293 posted on 10/19/2003 10:01:32 PM PDT by Alamo-Girl
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To: null and void
I don't see that.

Does the path God and our free will chose to get where we are matter more than where we arrived?

I am not sure of what you are saying, could you please restate it. I will also try to clarify my point.

The punishment for Adam's disobedience was death. As the Apostle Paul stated, "The wages of sin is death".

Jesus Christ lived a perfect life to redeem man's inheritance (The sinless God-Man), and then He died on the cross to redeem our necessity for the punishment of death for our sins.

If evolution is true, Adam had an earthly father who naturally died. The choice of disobediance Adam made was made for him by God, if God used natural evolutionary methods to bring about Adam. Therefore, death was not a punishment, and more importantly the wages of sin are not death and there was no need for Jesus to live a sinless life to conquer the punishment of death.

I choose to trust in the death and resurrection of our sinless Redeemer Jesus Christ, so that we may live sinlessly, in our resurrected glorified bodies, eternally with God.

294 posted on 10/19/2003 10:46:50 PM PDT by bondserv
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To: Junior
Using the Bible to prove the existence of God

Please re-read my posts. I NEVER stated that God's existence could be proven. In fact, I stated exactly the opposite. Not much of a God, if we can prove him. There is a difference between evidence and proof, but it sounds like many here don't understand it.

295 posted on 10/20/2003 7:01:34 AM PDT by asformeandformyhouse
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To: bondserv
AH! I understand your point now. I don't necessarily agree with you, but you are at least clear, consistant and concise in making your case.

One could also argue that Adam was special, God breathed life (a soul) into him. He was the first HUMAN, the first of the body type with a soul. That his sire and dam died as souless animals is irrelevent.

Bodys die. Even God made flesh died. "The wages of sin is death", so apparently are the wages of virtue.
296 posted on 10/20/2003 7:25:02 AM PDT by null and void
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To: null and void
One could also argue that Adam was special, God breathed life (a soul) into him. He was the first HUMAN, the first of the body type with a soul. That his sire and dam died as souless animals is irrelevent.

Thanks for responding. I have heard the argument that Adamic man started with Adam. This inevitably leads down the path of, "who among us is not an Adamic man"?

Bodys die. Even God made flesh died. "The wages of sin is death", so apparently are the wages of virtue.

Most Biblical scholars believe Adam would have existed eternally if he retained his innocence, for without sin (the fall) there is no death. (The wages of sin is death).

The greatest thing for us in the Gospel is that God's perfect plan is so full of grace, in that we still sin after we become believers, but because of what Christ did on the cross, the judgement for our sins was placed on Christ. Christ died and conquered death through His resurrection, as it will be with us. For believers in Christ, sin has lost it's deathly hold because of what He accomplished on the cross. Jesus Christ living a sinless life making him worthy of sacrifice and resurrection. Free at last.

Of course a believer engaging in habitual sin dishonors Christ's sacrifice, and often prompts decisive action by the Lord. This usually results in hindered fellowship with God, and a lack of blessings in ones life. However, the Body of believers in contact with a habitually sinning Christian are commanded to call them to account.

Needless to say, it is best to abide in Christ. Spiritual blessings in this life, and promised rewards in heaven are strong motivators to deal forthrightly with personal sin.

297 posted on 10/20/2003 8:22:44 AM PDT by bondserv
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To: bondserv
This inevitably leads down the path of, "who among us is not an Adamic man"?

The Clintons? I'm serious.

298 posted on 10/20/2003 8:28:50 AM PDT by null and void
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To: null and void
We could probably trace their ancestry to the Neander valley. They tell tal tales you know.
299 posted on 10/20/2003 9:11:32 AM PDT by bondserv
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To: bondserv
LOL!

Seriously, who did Cain marry, if not one on the unsouled pre humans?
300 posted on 10/20/2003 10:24:16 AM PDT by null and void
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