Of particular interest to me was the discussion of human brain evolution from Australopithecus Africanus onwards, and how each species' brain was an improvement on the old, to the detriment of our cousins within the genus. He does this by essentially taking the ~14 billion years of time since the Big Bang occurred and scaling it onto a typical 12-month calendar. Carl Sagan takes us on a great adventure, offering his vivid and startling insight into the brain of man and beast, the origin of human intelligence, the function of our most haunting legends - and their amazing links to recent discoveries. When archaeologists recently announced the discovery of cave paintings by neanderthals, I was not the least bit surprised.

My initial interest was to find out what he thought about the probability of intelligence developing.

The book offers to explain the evolution of the human species from the beginning of the Big Bang to our current time period. Sagan advances a chilling and all too likely hypothesis, that humans killed off apes who they thought came dangerously close to mimicking their linguistic capabilities. Sagan speculates on theories that even now are being confirmed -- such as that structures inside the brain are responsible for spiritual or religious experiences or ecstasy.

Carl Sagan served as the David Duncan Professor of Astronomy and Space Sciences and Director of the Laboratory for Planetary Studies at Cornell University.The word "speculations" is indeed in the title yet it feels like it would also be easy to miss that point while reading this.

This part provides a good segue into the even more interesting part of the book which deals with some fascinating speculations on the reptilian origins of human intelligence. Sagan tackles a topic that is far from his expertise – the evolution of human intelligence – and largely succeeds in presenting highly thought-provoking theses for us to ponder. My field is not science, so The Dragon's of Eden was my first encounter with the idea of the tripartite brain. this is the kind of book, if there is such a one, that you sprinkle salt on and gobble up in one bite. I do believe that he is a bit heavy handed with some of the science, more so than is probably necessary here and making the book feel over-long, but it is generally speaking an interesting book.The 103 third parties who use cookies on this service do so for their purposes of displaying and measuring personalized ads, generating audience insights, and developing and improving products.