Cryophilia OP , 6 days ago The failure to develop photosynthesis is the filter. I don't know how you're not getting this. No photosynthesis, no complex life, no sentience, no interstellar civilization.
The failure to develop photosynthesis is the filter. I don't know how you're not getting this. No photosynthesis, no complex life, no sentience, no interstellar civilization.