@Intractable Potsherd
"Don't forget that 20000 years ago, humans were quite happily living in a climate we would regard as inimitable to life today."
What?
Inimitable? ..to life? What does that even mean in this context?
Life currently occupies a greater range of temperatures and climates today than it did 20,000 years ago, when most of the world was glaciated and temperature were plateaued between extremely cold or extremely hot. These days we still have pretty much the same extremes, but now the middle stretch of temperatures is more populated. There is life from the Arctic to the fringes of underwater volcanoes; in both oxygen rich and oxygen poor environments; there is life practically everywhere, and there has been since it got a foothold billions of years ago.
But that doesn't mean we would *choose* to return to these extreme conditions, just that enough of us survived them to carry on the human race.
Biting the hand that feeds IT
