There is sufficient qty. of life on Earth to affect geophysics, cf. []. And actually has been for some time. When you see bands of iron in a geological record,

There is sufficient qty. of life on Earth to affect geophysics, cf. []. And actually has been for some time. When you see bands of iron in a geological record, it's because archaeobacteria were filling the ocean with oxygen and causing iron to oxidise. When there was no more room for dissolved oxygen in the sea, the excess took to the skies... the Great Oxygenation Event [] https://en.wikipedia.org/wiki/Deep_carbon_cycle https://en.wikipedia.org/wiki/Deep_carbon_cycle