Quite frankly an amazing book, and one of the very few I'd suggest is a MUST read. If you're ready to let go the myth of the hapless 'noble savage' and to release your mental image of a loin-clothed squaw with a single rear rolling down her cheek, and are ready to consider the possibility of fairly advanced cultures, of (as what is known as 'disturbance theory') the idea that the native cultures of the Americas had a massive and active, deliberate impact on the physical world around them, perhaps in some ways as much or more than we, then perhaps you should read this book and discover why the Amazon isn't quite how you think of it, how the terrain the first European settlers encountered was in many places a terraformed landscape, and generally challenge all your preconceived notions about pre-columbian America.