This book’s premise makes a lot of sense and could explain the development of the tremendous variety of civilizations and cultures over the last 10,000 years. However, it seems a rather simplistic view - basically saying that the root cause of their differences is their geographic location and the ecosystems that accompanied those. This eliminates all other potential factors such as the creative forces of communal human interaction, genetics, chance, the impact of historical events, and religion, to name but a few. Anthropologists call this line of thinking ‘geographic determinism’. Many of them really do not like his theory and believe it to be inaccurate.
But - it’s a brilliant piece of cross-discipline synthesis and fun to read . Except for the fact that, as many others have noted, it’s way too long and repetitive. Getting paid by the word? Could have been about 1/3rd the size. But one can skim right? So read on - it’s worth it.