This is one of the best documetaries I've ever seen. It's a superbe example of multidisciplinarity: a great mix of planetary science (geology, climate studies...) with history. I had never seen it presented this way and it works wonderfully. Plus, the presenter, Dr Iain Stewart, does an amazing job at sharing his passion and knowledge of the subject. The fifth episode, Human planet, should be mandatory viewing for everyone in order to gain a better knowledge of our influence on the planet! I highly recommend it!