Anton Petrov has a video today discussing the Silurian Hypothesis, which was a thought experiment dreamed up by a couple of scientists around 2017 about whether we could detect prior, non-human civilizations that may have existed millions of years ago on this planet. The title comes from a Dr Who episode about the Silurians, a civilization that existed on Earth before humans.

Youtube Video

the tl;dr is that basically we don’t have good ways of doing this, but watch the video.