We like to think we’re the pinnacle of intelligent life, but were humans really the first to evolve conceptual, self-aware, logical consciousness on Earth? Could an advanced technological civilisation have emerged before? If so, what happened to it? And if our planet produces many kinds of intelligence – octopuses have nine brains! – what is it about Earth that makes intelligent life likely to evolve here?  Evolutionary biologist and writer Dr. Henry Gee joins Ananyo Bhattacharya to talk about the so-called Silurian Hypothesis and whether humans really are Earth’s first intelligent inhabitants. Every Monday and Thursday WHY? takes you on an adventure to the edge of knowledge, asking the questions that puzzle and perplex us, from the inner workings of the universe to the far reaches of our dreams. Follow on your favourite app so you never miss an episode. WHY? was written and presented by Ananyo Bhattacharya. Audio production by Jade Bailey. Artwork by James Parrett. Music by DJ Food. Exec Producer: Jacob Jarvis. Lead Producer: Anne-Marie Luff. Group Editor: Andrew Harrison. WHY? is a Podmasters Production. Instagram | Twitter Learn more about your ad choices. Visit podcastchoices.com/adchoices