"As a species we seem to be a cancer on the planet." This platitude is actually interesting in this context. It connects multiple threads: * One of the previo

"As a species we seem to be a cancer on the planet." This platitude is actually interesting in this context. It connects multiple threads: * One of the previous major extinctions was the Oxygen Holocaust [1], caused by photosynthesizing cyanobacteria. It killed pretty much everything alive back then. And turned our Earth into a snowball to boot. * This oxygen is a major contributor to CANCER, via free radicals etc. It leads to a faster (and more ruthless, more side effects) metabolism, enabling evolution of highly reactive creatures such as us. * And trees, the "speaking organisms" under discussion, are one of the major producers of this highly volatile, carcinogenic O2 substance. Tongue in cheek? Maybe. But hopefully no worse than the naive "humans are a cancer to the planet". [1] https://en.wikipedia.org/wiki/Great_Oxygenation_Event https://en.wikipedia.org/wiki/Great_Oxygenation_Event