Ancient Microbes Responsible for Breathing Life Into Ocean

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Ancient Microbes Responsible for Breathing Life Into Ocean 'Deserts'

ScienceDaily (Aug. 23, 2010) â€" More than two and a half billion years ago, Earth differed greatly from our modern environment, specifically in respect to the composition of gases in the atmosphere and the nature of the life forms inhabiting its surface. While today's atmosphere consists of about 21 percent oxygen, the ancient atmosphere contained almost no oxygen. Life was limited to unicellular organisms. The complex eukaryotic life we are familiar with -- animals, including humans -- was not possible in an environment devoid of oxygen...

The early Earth must have been an awesome place. 20 hour days and the Moon in an orbit just one 10th of its current distance leading to tides of 300 meters twice a day!

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Is it possible to know whether the unicellular organisms have had some sort of consciousness? This info completely deflates the creationist arguments. Eukaryotic life as we know it was not possible during the early stages of "creation." I think I've read somewhere someone said that life during the younger days of the earth was longer because of the abundance of oxygen, which was said to be much higher than today's level. Of course it is bogus. I forgot the feller's name.

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The atmospheric oxygen level over time has varied greatly as has that of carbon dioxide (which is now apparently at it's lowest levels ever).

When the earth coalesced there was a lot of free iron in the sea. This soaked up any free oxygen in the air and sea so levels of available oxygen was virtually nill. All life had to by anaerobic and oxygen was positively lethal to these organisms. With the evolution of cyanobacteria that photosynthesised the potential to oxygenate the atmosphere appeared. However there were still huge amounts of free iron in the seas and on land and for hundreds of millions of years this continued to oak up the oxygen produced by the cyanobacteria. and produce iron oxide (rust). It is this rust that became the iron ore deposited that we mine and then heat up to drive off the oxygen sequestered by it billions of years ago. Eventually all the free iron was oxidised and at that point the oxygen levels began to grow. This had a profound effect on the microbial life as the anaerobic life started to die off leaving the playing field wide open for the aerobic microbes. This I believe lead to the Great Oxygenation Event referred to in the Wiki link above.

The Carboniferous era represented the high points of both oxygen and carbon dioxide in the atmosphere where oxygen represented 30%(?) of the atmosphere and carbon dioxide was massively higher together with global temperature and sea levels. The whole world was covered with a massive forested biomass pumping out mega tons of oxygen and carbon dioxide. The result of this are the large coal seams we mine today. If we went back to the carboniferous era we would die as the carbon dioxide levels would have been lethal to us. In a sealed space it's not lack of oxygen that kills one it is carbon dioxide poisoning.