Skip to comments.Scientists find evolution of life
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.
Ok, so you're not asking, but I will give you my perspective anyway.
I initially found these science threads very interesting. I had access as a freeper to many very fine and well-educated minds, and I enjoyed the exchange of information. As time has progressed, however, these threads have been taken over by unnamed individuals with an agenda. The agenda has not been an honest exchange of ideas or viewpoints, but rather an attempt to discredit and hopefully eliminate genuine science from this forum.
As Conservatives, I and my fellow FR scientists are all too aware of the common misperception that highly educated people are by nature, Liberals. By participating and defending our positions within these threads, it is hoped that those misperception can be dispelled.
Unfortunately we, like all other humans, sometimes let emotions get the better of us...thus, the food-fights.
Anything else you wish me to find for you?
If you did not mean Genesis, then I apologize, but the fact remains, that you have stated that those who believe like you do are in fact Christians and those that do not believe like you do are not, and I find that offensive.
Aric, why am I not surprise that you and other read more in the words than what was written.
the fact is there ARE people who call themselves Christian who are not. Do you deny this fact? And I never said that all Christains that do not believe in Gen 1 are not Christians. You just read what you wanted to read. Why am I not surprised?
And what "bait" would that be?
I have lurked these threads for a long time and have seen both sides mock the other. That alone makes me not want to participate. I don't want to be mocked by evolutionists because I question the correctness of their position. I do not wish to be mocked by religious people who cannot accept that others might look for answers in other places than the scripture.
As such, these threads aren't a good place to come for honest discussion. You're going to be mocked if you don't conform to one side or the other. I've seen it.
It's just another form of tribalism. That's all. These great minds you refer to, if even they can be reduced to name calling- what's the point?
I view these threads as a form of exhibit of the uglier bits of the human condition. These discussions reek of the monkey house at your local zoo. Dominance, power displays, group dynamics. I do not see humanity being uplifted on them. I see ugliness and I see both sides being to blame.
For the living, life is supposed to be a process of maturation, and those that don't progress and learn from mistakes are IMHO not truly "alive".
Cyberspace is no different from the real world. You've still got your turkeys, no matter how smart or well educated they may be. You've also got some really fascinating people who haven't had the benefit of higher education. The trick (and the "point"), if you're so inclined, is to excercise discrimination...throw out the bad and keep that which is worthwhile.
And if we did that with these threads, would we be left with anything other than a blank HTML document? I wonder.
And who gets to decide what is good and bad?
You do...as a sentient creature.
I am not impressed.
Then excercise your powers of discrimination.
Interesting. I seem to recall asserting you are in denial, and f.christian is vitrolic and hypocritical. I could care less about political correctness. As for proving his posts are vitriolic, that is self-evident, even to you. You mat as well challenge me to prove the sky is blue.
As far as your being in denial: given your reasoning, it would be up to you to proove that you are not. Good luck.
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