Posted on 10/30/2003 5:04:39 PM PST by Dales
LIVERMORE, Calif. -- A trio of scientists including a researcher from the Lawrence Livermore National Laboratory has found that humans may owe the relatively mild climate in which their ancestors evolved to tiny marine organisms with shells and skeletons made out of calcium carbonate.
In a paper titled "Carbonate Deposition, Climate Stability and Neoproterozoic Ice Ages" in the Oct. 31 edition of Science, UC Riverside researchers Andy Ridgwell and Martin Kennedy along with LLNL climate scientist Ken Caldeira, discovered that the increased stability in modern climate may be due in part to the evolution of marine plankton living in the open ocean with shells and skeletal material made out of calcium carbonate. They conclude that these marine organisms helped prevent the ice ages of the past few hundred thousand years from turning into a severe global deep freeze.
"The most recent ice ages were mild enough to allow and possibly even promote the evolution of modern humans," Caldeira said. "Without these tiny marine organisms, the ice sheets may have grown to cover the earth, like in the snowball glaciations of the ancient past, and our ancestors might not have survived."
The researchers used a computer model describing the ocean, atmosphere and land surface to look at how atmospheric carbon dioxide would change as a result of glacier growth. They found that, in the distant past, as glaciers started to grow, the oceans would suck the greenhouse gas -- carbon dioxide out of the atmosphere -- making the Earth colder, promoting an even deeper ice age. When marine plankton with carbonate shells and skeletons are added to the model, ocean chemistry is buffered and glacial growth does not cause the ocean to absorb large amounts of carbon dioxide from the atmosphere.
But in Precambrian times (which lasted up until 544 million years ago), marine organisms in the open ocean did not produce carbonate skeletons -- and ancient rocks from the end of the Precambrian geological age indicate that huge glaciers deposited layers of crushed rock debris thousands of meters thick near the equator. If the land was frozen near the equator, then most of the surface of the planet was likely covered in ice, making Earth look like a giant snowball, the researchers said.
Around 200 million years ago, calcium carbonate organisms became critical to helping prevent the earth from freezing over. When the organisms die, their carbonate shells and skeletons settle to the ocean floor, where some dissolve and some are buried in sediments. These deposits help regulate the chemistry of the ocean and the amount of carbon dioxide in the atmosphere. However, in a related study published in Nature on Sept. 25, 2003, Caldeira and LLNL physicist Michael Wickett found that unrestrained release of fossil-fuel carbon dioxide to the atmosphere could threaten extinction for these climate-stabilizing marine organisms.
So you are a Creationist. Great!
When it comes to the disciplines, I have the greatest confidence in math and geometry. To a slightly lesser degree, I have confidence in physics, chemistry and molecular biology; to a lesser degree, cosmology and astronomy; lesser still, archeology and evolution.
My value assessment has nothing to do with the volume of evidence - but it has everything to do with the kind of evidence. Moreover, it has everything to do with my confidence in any particular theory.
Going back to evolution theory, there has been a relatively recent involvement of mathematicians, information theorists and physicists looking at a variety of issues, e.g. ”What is Life?”, biological information content, complexity. At the same time, molecular biologists and geneticists are exploring genetic functions, in particular regulatory control genes. It appears these efforts are converging to a consensus that variation emerges from autonomous biological self organizing complexity (though different scientists use different words to describe it.)
This is all happening within conventional science – not a hint of creationism or intelligent design – yet the meaning is clear, at least to me.
The long standing theory of biological evolution involves the interworking of random mutation plus natural selection. No doubt both occur as we can see it happening in viruses and bacteria. And if that were the entire story, life would be a directionless walk - happenstance.
However, if variation primarily emerges within the constraints of autonomous biological self organizing complexity – then the walk is not directionless after all.
To science, such a determination would not even be a speed bump on the road to future discovery. But to religionists and philosophers it is equally significant to the last science bell-ringer: that the universe had a beginning.
I haven't seen any, perhaps we're reading them differently. Could you point out one that you think is an example of what you describe?
(against Christians who don't swallow the lie of evolution)
What about evolution do you consider a "lie"?
The war was against the religion of evolution, NOT "Freepers who who happen to accept evolution,"
You don't see these as attacks on Freepers who accept evolution?
This is brave new world order and conservatism on the FR ... is being hi jacked by this psuedo intellectual - PC nazis (( non pluralists - anti democratic - monopolists )) --- atheists - new agers ! Aren't these liberal republicans really ... anti conservatives --- moles - sleepers ? Will FR - America become a science fiction cult like you - yours .. Such is the hole - rot of evolution you are trying to drown civilization - America - FR under ! FR lib speak - think ... only --- you would like that !Or:
That is why threads get pulled around here - vile evolutionists not wanting to see the truth heard [...] to say as you do above that atheists, evolutionists, materialists which are allied with the NEA, the liberals, the Communists and were allied with the Nazis in destroying Christianity and civilized society are conservatives [on FR] shows extreme bias on your partYour side insult, and the mangement seems to look the other way.
"Your side" has gotten away with some amazing zingers as well. While some people have gone over the line at times, for the most part it has been within the realm of what is to be expected on threads that are, in essence, debates.
Meanwhile, one of the few posters who wanted to talk science gets banned.
I disagree that he "wanted to talk science". Instead, he wanted to denigrate science, most often by posting unsupported (and unsupportable) claims which were easily refuted, then avoiding attempts to get him to either support or retract them. How many times on this thread had he announced that he was "totally" right, and those he disagreed with were "totally" wrong? Most attempts to actually talk science with him just got repetitions of his original statements, or premature declarations of victory, or accusations of being a "liar", etc. That's not discussing science, that's... something else.
like is said...the management should be ashamed. It is something I would expect democrats to do...not conservatives.
On the contrary, Democrats don't attempt to maintain standards of civility. Conservatives do.
I'd like to second that, as well as say how much I appreciate her willingness to treat with respect those who hold differing opinions.
If the "departed" posters could have adopted similar outlooks, I believe they'd still be with us.
It's worse than that. Behe didn't even originate the concept of irreducible complexity, just the name.
I wish I could claim credit for this Darwinian model of irreducible complexity, but I'm afraid I've been scooped by eighty years. This scenario was first hinted at by the geneticist H. J. Muller in 1918 and worked out in some detail in 1939.6 Indeed, Muller gives reasons for thinking that genes which at first improved function will routinely become essential parts of a pathway. So the gradual evolution of irreducibly complex systems is not only possible, it's expected. For those who aren't biologists, let me assure you that I haven't dug up the half-baked lucubrations of some obscure amateur. Muller, awarded the Nobel Prize in 1946, was a giant in evolution and genetics.From Darwin v. Intelligent Design (Again).
Behe appeared to have lifted Muller's concept, discarded Muller's answer to how such things evolve, coined a jazzy name, and compared himself to Newton!
I don't agree here. Evolution is a scientific theory that describes the evidence discovered to date. Should new credible evidence arise that undermines the current theory, it will either need to be scrapped, or modified to fit that evidence. Such is science.
Evolution does not address a creator in either a positive or negative way. However, the supporting evidence does overwhelmingly show both an ancient Earth and ancient universe measured in the billions of years.
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