Origin of Life: early land life (Introduction)

by Balance_Maintained , U.S.A., Tuesday, July 30, 2013, 11:54 (4135 days ago) @ dhw

TONY: We have a pretty strong estimate of what the early atmosphere was like. There is strong reason to suspect that the early atmosphere was laden with large levels of CO2, and limited oxygen. Plant respiration could use that and gradually bring the O2 levels up to the level where non-plant live could exist without dying. With the exception of extremophiles, the vast majority of animal life needs oxygen to survive. The logical conclusion is that the CO2 rich atmosphere was converted to the proper balance of O2 in the simplest manner, i.e. plants.
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>DHW: It's certainly a logical conclusion that plant life prepared the way for diversified animal life. That concept fits in nicely with evolution. We were asking, though, why there was no explosion in plant life until after the Cambrian, and so I thought you might have a teleological explanation, as opposed to my evolutionary ramblings.-No explanation at all, and that was my original point. If the neo-evolutionary theory were correct, then in the 3.3byn between vegetable life first appearing and the Cambrian explosion, we should have seen much more diversity and complexity in the plant life than we do, instead of it all appearing in a geological instant and diverging wildly over the span of a few hundred million years.

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What is the purpose of living? How about, 'to reduce needless suffering. It seems to me to be a worthy purpose.