>>11840124https://www.centauri-dreams.org/2018/04/18/civilization-before-homo-sapiens/We’re talking non-human cultures if we go back far enough, and with the passage of hundreds of millions of years, evidence becomes more than a little problematic. Frank has just written a piece for The Atlantic that pulls out the major themes of the paper. Was There a Civilization On Earth Before Humans? puts the matter succinctly. Because when you talk about direct evidence of an industrial civilization, we’re dealing with a geologic record that makes it all but impossible to probe past the Quaternary period, some 2.6 million years ago.
We can obviously study earlier eras, but as the authors point out, the largest extant surface area is in the Negev Desert, in southern Israel, which can take us back 1.8 million years. Earlier than the Quaternary, we rely on exposed surfaces unearthed through excavation, drilling or mining, while our study of ocean sediments faces the fact of recycling ocean crust, so that our evidence is for periods that post-date the Jurassic; i.e., we can go back some 170 million years.
