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.
Cripes, hubris evolved into an art form.
Why don't you fellows quit circling, form your own party and see if you can outpoll the libertarians. Can't wait to see the battle of the libertarians and the scientarians for the infamous 1/2%.
You didn't and since all your posts are short there's no way to know quickly what you believe. If the original question was not loaded as I suspected I apologise.
You warn people to their face. My last post. I'm outta here. God Bless you. BYE.
Yes! But man's perception and understanding changes. You understand more now than when you were a child.
We see and understand only part of God's truth. What is evolving is our perception and understanding of that truth.
It is like understanding the principle of mathematics. The truths of mathematics have always been there and always will be there and as we understand those principles we can put them to good use. The principles of Life (God's Law) have always been there and always will be there and as we understand them we can live as we were intended to live. Human, material evolution is proceeding toward the spiritual, eternal creation which has always existed. Do you really believe that we (humans) are now living in accordance with God's eternal and perfect laws?
You're right. It's not the Christians, it's the anti-evos who are weakening the GOP by grossing out conservatives who happen to agree with standard biology, geology, etc.
It's so ironic. Conservatives normally use history, current observation, logic, etc, as opposed to emotion, to come to an understanding of political issues. People who use these techniques to understand the living world almost unanimously agree that evolution is the best fit to the data. These people are natural conservatives, imo.
It is dishonest to teach something as 'science' when practically no working scientist subscribes to it. Do you really want teachers lying to the pupils?
Remember:
1) Most Christians are not creationists or id-ers, not even in the USA, certainly not worldwide.
2) Creationism is enforced by law in Muslim countries. I'm not 100% sure, but worldwide, I'd bet most creationists are Muslims.
Ooooooh! I don't wanna go there. But I needed to drop a placemarker.
Correct. But then, I've not seen anyone make that claim here, either.
It is similarly a myth that "evolutionists" are bringing down the Republican party (or society/America in general). And I *have* seen *that* claim made.
Our fight is against liberals and liars of the left.
I agree, which is why I don't understand why a handful of Freepers would choose to make war on those Freepers who happen to accept evolution.
Would you agree to an amendment to the first sentence, that practically no working scientist believes that one can prove creation via science?
With respect to Intelligent Design, there are some interesting arguments made, but to date no truly satisfying scientific experiments, is my understanding.
Scientists don't reject faith, they just can't prove religion in the laboratory.
Maybe you said it better than I am suggesting, I just want to make the extra effort to find common ground, especially when there are so many hard feelings already.
wow, I'm speechless.
Moral: Don't call JR and the mods liberals and put words in their mouths.
PS. Welcome back, I thought you were going to be a DU-II-er from now on.
I was tempted to mention the plastic shiv remark, but you're making it more obvious anyway. Not sure why you want to brand that part of your background on your forehead.
You've been around long enough to know that there are Christians on both sides of this debate, so are the other Christians simply deluded? Or is it that you are blessed to see the absolute truth every time?
Or perhaps, you would care to rephrase your argument?
Have you personally received His forgiveness for your sins?
Salvation is a gift from God that needs to be received. Your ticket to pardise is waiting for you at will-call, get down there and pick it up. The only problem I see you all have is that will-call is in the Creationist section of town.:-)
Wouldn't dream of questioning it.
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