Metazoa: Animal Minds and the Birth of Consciousness by Peter Godfrey-Smith. Stick to the first book. This is just an extension of that. In an attempt to examine the origins of animal consciousness, Peter Godfrey-Smith has written what is essentially a semi-coherent, superficial mish-mash of science, philosophy and memoir. The author starts off with sea sponges and ends up with vertebrates, writing vaguely about their nervous systems and how they sense/interact with their environment. The "animal facts" are very interesting. So are the vignettes about the author's experiences with animals when diving. However, Godfrey-Smith is not very good at explaining why any of these "animal facts" and experiences are relevant to his thesis/hypothesis, or how it fits into the bigger picture. An intelligent reader that is paying attention can figure it out, but the book isn't particularly well written, the topics aren't covered deeply enough to be really useful, and Godfrey-Smith tends to ramble too much. Maybe a different organizational structure would have helped? Covering animals as they evolved does tend to lead to rather a lot of repetition. This book lacked substance and was therefore, disappointing. If the Peter Godfrey-Smith ever wrote a diving memoir with interesting "animal facts" thrown in, I would read that (he is good at the memoir stuff), but I would have to think really hard about another science-philosophy-memoir mishmash.