The scuba-diving philosopher explores the origins of animal consciousness.

Dip below the ocean’s surface and you are soon confronted by forms of life that could not seem more foreign to our own: sea sponges, soft corals and flower-like worms, whose rooted bodies and intricate geometry are more reminiscent of plant life than anything recognisably animal. Yet these creatures are our cousins. As fellow members of the animal kingdom – the Metazoa – they can teach us about the evolutionary origins of not only our bodies, but also our minds.

In his acclaimed book, Other Minds, Peter Godfrey-Smith explored the mind of the octopus – the closest thing to an intelligent alien on Earth. In Metazoa, he expands his inquiry to animals at large, investigating the evolution of experience with the assistance of far-flung species. Godfrey-Smith shows that the appearance of the first animal body form well over half a billion years ago was a profound innovation that set life upon a new path. He charts the ways that subsequent evolutionary developments – eyes that track, for example, and bodies that move through and manipulate the environment – shaped the lives of animals. Following the evolutionary paths of a glass sponge, soft coral, banded shrimp, octopus and fish, then moving onto land and the world of insects, birds and primates like ourselves, Metazoa gathers these stories together to bridge the gap between matter and mind and address one of the most important philosophical questions: what is the origin of consciousness?

Combining vivid animal encounters with philosophy and biology, Metazoa reveals the impossibility of separating the evolution of our minds from the evolution of animals themselves.