good one, Lighter   lol

I remember when I first realized that the original air pollutant was ... drumroll... O2 ... from those pesky photosynthetic organisms.... :)

and not too long ago I watched a show that discussed the expected changes as our sun started to age and the resulting changes in solar radiation would result in the likely demise of photosynthetic organisms and "life on earth" would likely be little different from the original primordial slime.... humbling, don't you think