How many humans can the earth support?
Will water, food, space or warfare be the limiting factor?

How much crude oil, natural gas, or coal can humans extract from the earth at reasonable cost?

Algae store Omega-3 oils to use as food when the sun is not shining.
There is A LOT of algae in the oceans, lakes and rivers.
What percent of the total algae would humans have to collect and squeeze to provide enough oil to power all of human civilization?
What should be done with the non oil leftover body parts of that fraction of the algae?

Long long ago blue-green algae started turning sunlight into food,
left solid wastes as distinctly looking rock (Stromatolites)
and let loose a gaseous waste (Oxygen) too,
which started a whopper of “climate change”.

Has human caused “climate change”
got any where close to algae caused climate change?

Algae creating stromatolites rock mounds are still alive today,
but just in spotty unique places.
Should we search these algae out,
and kill them for their past climate “sins” ?

Hmmmm - could algae be tricked into transferring water to the Colorado watershed?