Prior to the Industrial Revolution, the earth's level of atmospheric CO2 was becoming dangerously low as the planet was suppressing more carbon, then it was releasing. Atmospheric CO2 had fallen to 280ppm.
The planet greened and life boomed 100 million years ago, when CO2 levels average 1000-2000 ppm; studies show the optimal level to support plant life is 1500ppm. About three times the current level. If CO2 falls below 150ppm, plants will begin to die along with the planet.
There is an emerging study that treats the planet like a singular organism and humans as simply a component of the planet. This study argues that at some point, humans naturally evolved to unlock the carbon that had been sequestered, thus filling an important niche in a planet that had far to little CO2 to maximize "life".
This presents a different view of "humans". One of the critical niches we fill is the release of CO2. And since the industrial age, we have gotten quite good at it. The question then is not whether humans should be burning fossil fuels to release CO2, but what happens when there is not more fossil fuel to burn. What will become our new ecological purpose? What new niche will we fill?
In other words, if our primary evolutionary purpose was to add to the atmospheric CO2 levels what will happen to humans when that mission is realized and atmospheric CO2 triples from current levels?
Science argues that humans will find a new ecological niche to fill, or we will go extinct. At some level we have begun to drift towards extinction due to the lower rapidly declining rates of human reproduction. At some level, our species realizes the planet has no need for more of us, so we are producing less of us. And scientists are predicting populations will begin crashing around the globe.
In other words, we think we are "in charge", but we are simply "pawns" in the global ecological system. The other option is to find a new niche to fill. I am optimistic that humans will adapt and find that new niche. If that "niche" is smaller than the colossal challenge of unleashing sequestered carbon, than the global populations will be smaller. That is fine. That is how evolution within an ecosystem works.
Producing CO2 is not our only function (all animals do that; we just do it better). This view of the planet as a singular organism raises more questions than it answers. Are we really "the brains" behind our planet's existence or simply a "player" that thinks to highly of our role.
Because of the adaptive nature of humans, I expect mankind in some form to persist until some sudden global event like a meteor crashing into the planet or a nuclear war resets the clock.
