Alien life could be turning harsh planets into paradises — and astronomers want to find them

Dec 20, 2022
So, IF life manages to get started in a marginally habitable environment, and IF that life form turns out to have an effect on that environment that makes it a bit more habitable, THEN you could get a snowball effect (positive feedback) in which the better environment helps the life form to flourish, which increases the effect that made the environment better, and so on ... .

On the other hand, if the life form has an effect that makes the environment less habitable, then that effect might put that life form out of existence, or create an equilibrium that limits the life form's progress. Perhaps creating a cyclic boom-and-bust pattern.

What I wonder is if this phenomenon of a life form affecting the environment, which in turn affects the life form, would imply a second-order Darwinian effect. What I mean is, if the life form has a mutation that causes it to improve its environment, does this create an evolutionary pressure to spread that mutation? Conversely, if the mutation degrades the environment, does this create an evolutionary pressure against it?
Jan 8, 2023
I believe that scientists when their looking for habitable planets, instead of looking for hydrogen, methane or carbon dioxide, should be looking for an Earth-like Van Allen belt which would be evidence of an atmosphere and strong gravity that would allow life to begin.