As with most anthologies, some of the essays were better than others. It was refreshing to hear indigenous perspectives on (neo-)colonialism, past and present oppression, and steps being taken to re-indigenize their cultures. That they have suffered so much and been colonized so much is heartbreaking.
Some of the essays were long on broad concepts but short on specific details, particularly Indigenous Knowledge. There were hints that some of it is secret or guarded, which I respect and is understandable.
I understand indigenous spirituality to be what is called animism. This actually has a basis in science, as all matter is essentially energy condensed to different vibrations and complexities. This also informs their intimate relationships with plants, animals, water, mountains, and natural forces. But several of the essays referenced God or Creator or Sky Father, and I have to wonder if this is at least partly a result of Christianization. Other sections were a bit too "spiritual" for me, as an atheist, to fully appreciate.
Some essays seemed to be almost acquiescing to so-called sustainable development, which is unfortunate.
Others were perhaps a bit too dismissive of science in favor of myths and stories. Again, this is understandable as a means to reclaim heritage and fight western worldview. Certainly science suffers from funding bias (mostly military and corporate), Cartesian reductionism and mechanical worldview, and the obsession with applications in technology that is evermore powerful beyond our collective wisdom. But I digress.
I appreciate the work of the Bioneers and the contributors. When this civilization crashes, as they all eventually do (see peak oil), the indigenous peoples of the world will be among the best equipped to survive and thrive, if they can reclaim their authentic roots in time.