Oxygen and the Cambrian (Evolution)

by dhw, Monday, December 20, 2021, 06:45 (852 days ago) @ David Turell

dhw: We are trying to explain speciation. Do you think it was sheer coincidence that oxygen appeared in large quantities and new species appeared at the same time? Or do you think the new species appeared BEFORE the increase in oxygen?

DAVID: Coincidence doesn't speciate. Oxygen was around in large amounts long before the Cambrian.

dhw: I’m glad you agree that it is NOT coincidence. What happened before the Cambrian is irrelevant to what happened during the Cambrian. If the oxygen theory is true, this leaves you with my second question: do you think your God created the new species “de novo” BEFORE the increase in oxygen? Here is an interesting article in support of the link between oxygen and speciation as well as extinction:
[…]
dhw: I would regard this as typical of evolution in general: organisms RESPOND to environmental change in three possible ways: adaptation, innovation or death.

DAVID: I'm sure I presented this article here when it appeared, and my comment remains the same as before. First, thanks for re-finding it. Second: oxygen levels, when high, allow for more complex organisms. But the drive for complexity comes from something else, which we debate. I'll stick with God.
As the article says: He [researcher] emphasizes that increased oxygen isn’t the sole cause of increased diversity. Once complexity evolved, it could compound itself, driven by ecological interactions. But He argues that for this to be possible, higher oxygen levels were necessary. I agree. Not causing but allowing.

I also agree. As I pointed out before, you cannot have diversity if you do not have life forms that can diversify! The question remains: do you believe your God designed the new species de novo BEFORE conditions changed or in response to the new conditions?

DAVID: https://www.quantamagazine.org/rapid-oxygen-changes-fueled-an-explosion-in-ancient-anim... (this address should work, the one above didn't)

Thank you.