Oxygen is why plants are stationary and animals move, because oxygen gives animals the energy to move (and taxes the plants for making it!).
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On that note there are on average 5000 mitochondria in each cardiac cell. If it weren’t for eukaryotes evolving there would be no animals.
Perhaps that abundance of oxygen is why the eukaryotes changed so quickly. I figure vast amounts of oxygen had to be pumped out before it stopped reacting with everything it touched. It formed oxidation layers that prevented further depletion of oxygen. The poisonous nature of this reactive element no doubt killed off a bunch of species forcing a change from that as well.