Since my introduction was so long I posted it separately.
FourCornersFreePress, December 2019
In the first half of this look at Earth’s 4.6 billion year old pageant of Evolution, scaled down to 24 hours, Earth’s first enduring Life took about 4 hours to claw together an existence within very tiny, very simple, very protective sacks, against an extremely harsh environment.
After that, Evolution progressed very slowly. Why? Because Earth’s hostile environment provided limited means, this stifled further development. Which brings us to a key early scientific breakthrough in perspective, namely that an organism cannot be understood without also understanding the environment it lives within.