Strongly upvoted because the brainy dinosaurs possibility is pretty interesting. Any remnants of their civilization such as anomalous iron deposits, would likely be buried too deep for us to stumble upon it. The minute quantities that would make it closer to the surface could be easily dismissed for a variety of factors.
social (it’s known that their nests were shared by multiple females) [4]
massive concentrations of atmospheric CO2 during the time (higher than today) [3], followed by one of the largest extinction events in the Earth’s history (the Cretaceous–Paleogene extinction event)
However the chart in your last link shows the peak of that concentration seems to be ~120 million years ago, with a pretty steep decline in geologic terms afterwards, ~55 million years before the K-T extinction.
Good catch! It seems that although CO2 was much higher than today, it was mostly in decline during the Troodon times. Doesn’t look like an effect of a tech civilization.
Strongly upvoted because the brainy dinosaurs possibility is pretty interesting. Any remnants of their civilization such as anomalous iron deposits, would likely be buried too deep for us to stumble upon it. The minute quantities that would make it closer to the surface could be easily dismissed for a variety of factors.
Among dinosaur candidates, Troodon seems to be the most interesting:
a bipedal species, with agile hands and stereoscopic vision [1]
the structure of the teeth suggests a preference for soft food [2]
a large brain for the animal’s size [1]
social (it’s known that their nests were shared by multiple females) [4]
massive concentrations of atmospheric CO2 during the time (higher than today) [3], followed by one of the largest extinction events in the Earth’s history (the Cretaceous–Paleogene extinction event)
However the chart in your last link shows the peak of that concentration seems to be ~120 million years ago, with a pretty steep decline in geologic terms afterwards, ~55 million years before the K-T extinction.
Good catch! It seems that although CO2 was much higher than today, it was mostly in decline during the Troodon times. Doesn’t look like an effect of a tech civilization.