Was there a technologically advanced species living on Earth long before humans? And if one had existed, how would we know? (Updated from 2022)For more, go to http://vox.com/unexplainableIt’s a great place to view show transcripts and read more about the topics on our show.Also, email us! unexplainable@vox.comWe read every email.Support Unexplainable by making a financial contribution to Vox! bit.ly/givepodcastsLearn more about your ad choices. Visit podcastchoices.com/adchoices