One of the blessings of Covid-19 lockdown was discovering the wildlife cameras streaming on the internet in real time. With a click it became possible to observe brown bears catching salmon in Alaska, sea lions clambering on and off a rocky beach in British Columbia, and white-bellied sea eagles nesting in an eyrie high in bushland on Sydney’s fringes. Watching newly fledged eaglets literally stretching their wings as they stare across the treetops, it’s impossible not to wonder what they must experience in that moment, as they sense for the first time the instinctive urge to take flight. What does it feel like to be a bird? What sense does a bird have of itself as a subjective, experiencing being? How might its consciousness be characterised?

Scuba diving along the Australian coast, and contemplating octopuses as they wrestled near piles of empty scallop shells, Peter Godfrey-Smith, a philosopher of biology at the University of Sydney, found himself asking similar questions. His first attempt at uncovering an answer was Other Minds: The octopus and the evolution of intelligent life (2017). Metazoa: Animal minds and the birth of consciousness, his new book, extends that quest. Godfrey-Smith moves beyond cephalopods (molluscs such as octopus) and explores the evolution of consciousness more broadly.