I mean, the guy putting forward this theory is an expect in fluid dynamics. So I expect the answer is "yes, animals do make a big impact on oxygenation of the o

I mean, the guy putting forward this theory is an expect in fluid dynamics. So I expect the answer is "yes, animals do make a big impact on oxygenation of the ocean". Here's another study from 2014 that talks about the link between animals and oxygenation of the oceans. (This paper just focused on the mixing of oxygen in the ocean, it doesn't claim that more ocean-oxygen led to a higher oxygen world like the OP. https://www.sciencedaily.com/releases/2014/03/140309150540.htm https://www.sciencedaily.com/releases/2014/03/140309150540.h... )