Posted on 12/10/2006 5:29:49 PM PST by shrinkermd
Oxygen may be the clue to first appearance of large animals, says Queens prof
The sudden appearance of large animal fossils more than 500 million years ago a problem that perplexed even Charles Darwin and is commonly known as Darwins Dilemma may be due to a huge increase of oxygen in the worlds oceans, says Queens paleontologist Guy Narbonne, an expert in the early evolution of animals and their ecosystems.
In 2002, Dr. Narbonne and his research team found the worlds oldest complex life forms between layers of sandstone on the southeastern coast of Newfoundland. This pushed back the age of Earths earliest known complex life to more than 575 million years ago, soon after the melting of the massive snowball glaciers. New findings reported today shed light on why, after three billion years of mostly single-celled evolution, these large animals suddenly appeared in the fossil record.
In a paper published on-line in Science Express, Dr. Narbonnes team argues that a huge increase in oxygen following the Gaskiers Glaciation 580 million years ago corresponds with the first appearance of large animal fossils on the Avalon Peninsula in Newfoundland.
Now for the first time, geochemical studies have determined the oxygen levels in the worlds oceans at the time these sediments accumulated in Avalon. Our studies show that the oldest sediments on the Avalon Peninsula, which completely lack animal fossils, were deposited during a time when there was little or no free oxygen in the worlds oceans, says Dr. Narbonne. Immediately after this ice age there is evidence for a huge increase in atmospheric oxygento at least 15 per cent of modern levels, and these sediments also contain evidence of the oldest large animal fossils.
Also on the research team are Don Canfield (University of Southern Denmark) and Simon Poulton (Newcastle University, U.K.). Geochemical studies by Drs. Canfield and Poulton included measurements of iron speciation and sulphur isotopes to determine the oxygen levels in the worlds oceans at the time these sediments accumulated in Avalon.
The close connection between the first appearance of oxygenated conditions in the worlds oceans and the first appearance of large animal fossils confirms the importance of oxygen as a trigger for the early evolution of animals, the researchers say. They hypothesize that melting glaciers increased the amount of nutrients in the ocean and led to a proliferation of single-celled organisms that liberated oxygen through photosynthesis. This began an evolutionary radiation that led to complex communities of filter-feeding animals, then mobile bilateral animals, and ultimately to the Cambrian explosion of skeletal animals 542 million years ago.
As far as the age of the Earth, I am familiar with Ussher's Chronology and how he determined it but that is not Scripture itself. It is his calculations based on some assumptions he made. If the Bible itself clearly gave a specific date for the moment and week of creation, then I would accept that but it doesn't. There are many other reputable Christians and Biblical scholars that have different views on the age of the earth for several different reasons. This is one:
The Age of the Universe
http://www.freerepublic.com/focus/f-news/1576941/posts
As far as one of the issues with the age of the earth is the assumption that everything has always been as it is now. When man sinned, Scripture says that corruption entered the world. That indicates a change of condition in the physical world. In Genesis, there are descriptions of the world before the Flood and the conditions that existed then and they are different than they are now, another change. Those could throw a huge monkey wrench into the calculations of the age of the earth by radiometric dating and other geologic processes that could have proceeded at different rates. There have even been some cases where these processes aren't proceeding as expected even today. The Lost Squadron is one such example; the planes from WWII were found buried under 250 feet if ice in Greenland which doesn't fit at all with currently accepted ice built up time frames.
When the Bible states that something happened, there is no reason to interpret it in any other way. When poetry, allegories, parables are being used, it's pretty clear what they are and anyone with any working knowledge of grammar would know that those are not literal, especially when it is said *He told them this parable*. How can one be reasonably expected to take a clearly stated parable literally?
So I accept that God created things in the manner He did because it states it so clearly. The age of the earth and universe is more indeterminate, IMO.
However, not accepting the current scientific interpretation of the fossil record does not equate with a blanket rejection of science as a whole. Science does not rest on the ToE; the ToE rests on science. It's science as it stands today that is being used to support the ToE but the ToE cannot be used to support science. Also, there is the automatic assumption that if there's a discrepancy between science and Scripture, the Bible is automatically the document that is wrong because it doesn't agree with current scientific findings. But current scientific findings are just that- current, and are subject to change as new data comes in. Once new findings come in, the older scientific findings were shown to be incomplete of outright wrong. So how can something that subject to change be used to *disprove* something else? In order to do that it would have to be established beyond a shadow of a doubt that the science is right, true, and infallible and I don't think it's arrived there yet.
But where did the single cell animals come from?
And where did the water come from?
And how did the water freeze? Then melt?
I've always wondered why evolution is such a bristling threat to religious persons when, say - a medical scientist describing how the circulatory system distributes oxygen isn't an equal threat.
Evolution is "how" not "why".
Some of it's there as I said before and it's written in a manner which most anyone anywhere can understand. No one said it was a thorough university level treatment of the subject but just because it isn't, doesn't mean it's wrong. If that's the case, then is all high school and elementary school education is wrong because it's at a lower level and explained in terms geared for the age and ability of the students learning it? Because it isn't a thorough university level treatment of the subject area?
Its a book of stories, written for illiterate people, using stories and metaphors, not a book to teach someone how to interpret the world around them and unlock the mysteries of the world.
Well, that's only your opinion, which means that it's nothing more than that- the opinion of person out of 5 billion plus. That doesn't make it an established fact.
What hypocrisy? How have you determined that I am a hypocrite? In what areas have you determined that I am willfully ignorant? How do you know what I know and why?
Which is why I'm all for global warming. I don't care much for the alternative.
When one picks and chooses, for religious reasons, which parts of science to accept and which parts to reject, one is not doing science; one is engaging in apologetics (defense of religion).
The methods used to derive the theory of evolution are the same as for the theories explaining gravitation and germs, and all other scientific theories.
That some deny these theories for religious reasons does not detract from the accuracy of the theories in any way. (See tagline for the conclusion.)
Evolution is only a threat to their beliefs because they allow it to be.
Which doesn't say much for their higher reasoning.
How is the quest for knowledge about evolution a threat.
God gave you a brain, use it to its fullest. If God didn't want us to learn about evolution, He wouldn't have left so much data and clues.
It doesn't oppose God's word. You are a bible literalist, too bad, but the bible isn't a science book. Evolution does nothing to shake the faith of someone that is comfortable in their beliefs.
It takes so much effort these days to be so purposefully ignorant, you really are letting the higher functions of your brain go to rot.
It's Bushes fault!
Yup...
2 Corinthians 1
13. For we do not write you anything you cannot read or understand. And I hope that,
14. as you have understood us in part, you will come to understand fully that you can boast of us just as we will boast of you in the day of the Lord Jesus.
Likewise...
If God didn't want us to learn about Himself, He wouldn't have sent His Son to show us the Way.
NIV Colossians 1:15-21
15. He is the image of the invisible God, the firstborn over all creation.
16. For by him all things were created: things in heaven and on earth, visible and invisible, whether thrones or powers or rulers or authorities; all things were created by him and for him.
17. He is before all things, and in him all things hold together.
18. And he is the head of the body, the church; he is the beginning and the firstborn from among the dead, so that in everything he might have the supremacy.
19. For God was pleased to have all his fullness dwell in him,
20. and through him to reconcile to himself all things, whether things on earth or things in heaven, by making peace through his blood, shed on the cross.
9. For in Christ all the fullness of the Deity lives in bodily form,
10. and you have been given fullness in Christ, who is the head over every power and authority.
GOD's Word opposes it.
When evangelicals lose an argument, they have to quote the bible.
Use all of the brain God gave you.
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