A reminder of the rather more ancient civilisations imagined in the Silurian Hypothesis thought experiment of a couple of years ago: https://www.wikipedia.org/

A reminder of the rather more ancient civilisations imagined in the Silurian Hypothesis thought experiment of a couple of years ago: https://www.wikipedia.org/wiki/Silurian_hypothesis https://www.wikipedia.org/wiki/Silurian_hypothesis