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Did a low oxygen level delay complex life on Earth?


That’s often been suggested. Recently, some interesting evidence has turned up (the researchers estimate 1% of today’s level).

From the BBC:

The team analysed the chromium levels – a geochemical signature – of rock sediments from Australia, Canada, China, and the United States. This allowed them to understand how much oxygen would have been present.

They found a change in the chemical components of the rocks occurred about 800 million years ago, a period when oxygen levels began to rise rapidly, already documented by previous research.

Another researcher was more critical of the study and said the role of oxygen was overstated. Nicholas Butterfield of Cambridge University’s department of Earth Sciences said: “All geochemistry is drawn from marine rocks, it’s not directly measuring the atmosphere.

See, for example, Why life remained just slime for a billion years: Turns out low oxygen WAS to blame after all (?):

As the USD researchers who studied sponges showed, life forms do not universally need a lot of oxygen.

We are living on a planet where at last one bacterium “breathes” iron and another sulfur, the bdelloid rotifer dispensed with sex in favour of horizontal gene transfer, and the sea slug just incorporated its plant meals’ chlorophyll factories (chloroplasts) [Just what is going on with the slugs has been disputed.] It almost seems as if, whatever the deficiency, a life form will be found somewhere that can cope with it. But come to think of it, would any of the above-mentioned make good fossils? Maybe we just don’t know enough yet to be sure that the famously “boring billion” years was quite so boring.

Also: Animals didn’t “arise” from oxygenation, they created it, researchers say

Theory on how animals evolved challenged: Some need almost no oxygen


New study: Oxygenic photosynthesis goes back three billion years

We should organize a panel discussion with all these people.

See also: The Science Fictions series at your fingertips (origin of life)

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Andrew Snelling, a geologist, questions the assumption of a low oxygen early earth.
The notion of the earth’s early atmosphere being reducing and conditions on the early earth being anoxic is the geologic equivalent of an urban myth. The deepest and thus earliest rocks in the geologic record indicate there has always been lots of oxygen in the earth’s atmosphere. For example, in some of the earliest rocks are massive concentrations of iron oxides, which could only have accumulated under an oxygen-rich atmosphere. More details and examples can be found in this article “The First Atmosphere—Geological Evidences and Their Implications.” And conditions could not have been acidic either, because the earliest fossilized forms in the geologic record are stromatolites built by cyanobacteria that are identical to those still being built today by essentially the same cyanobacteria in places where the waters are not acidic and the atmosphere is oxygen-rich.
rf: About the first atmosphere: https://answersingenesis.org/age-of-the-earth/the-first-atmosphere-geological-evidences-and-their-implications/ About stromatolites: https://answersingenesis.org/origin-of-life/strelley-pool-stromatolites-blow-for-early-life/ About the early earth being anoxic: https://answersingenesis.org/theory-of-evolution/evolution-timeline/sea-sponges-challenge-traditional-evolutionary-view-of-how-oceans-became-oxygenated/ tjguy
Beau, agreed!
We should organize a panel discussion with all these people.
Good idea! Let the materialists all debate themselves. This example highlights the problems and limits of historical science. We can come up with a hundred different hypotheses. "Maybe this ....", or "Perhaps that...." If the hypotheses cannot be tested, what good are they as far as science goes? Data is data and no more. We don't protest the fact that they found a chance in the chemical composition of the rocks they were studying, but what that means is a whole different story. Here we get into the interpretation of the data. All data, in order to make sense out of it, must be put into some kind of a framework and interpreted. One possible result is the idea that perhaps low oxygen stymied the growth of early life. Fair enough. Makes sense in the evolutionary framework, but it cannot be tested. And it seems that there are many possible interpretations of the data even within the evolutionary framework. Not all agree with the suggested interpretation. One critical of the study said
“All geochemistry is drawn from marine rocks, it’s not directly measuring the atmosphere."
Just because there are a lot of different life forms does not mean that there was some type of atmosphere or period of history where such conditions were common. There are environments right now in this world where these organisms can exist. It might have been that way all along, but that idea does not fit the evolutionary framework. tjguy
It amazes me how evolution champions can't understand why so many people struggle with evolution. When a regular Joe like myself looks at the case for evolution I see little consensus aside from evolution is a FACT! Could be due to my ignorance I suppose. beau

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