Modern biology increasingly shows that no organism lives alone. Human bodies are not self-contained individuals but holobionts, communities of human cells, microbes, and other symbionts that develop, metabolize, and survive together. For developmental biologist Scott F. Gilbert, this understanding of life has consequences far beyond the laboratory. It calls for a new account of our responsibilities to one another and to the planet.
We Are All Lichens traces biology's shift from gene-centered explanations to a science of relationships, processes, and mutual dependence. Embryology shows cells forming one another through reciprocal induction. Studies of microbiomes reveal organisms as ecosystems. The concept of sympoiesis, or making-with, extends this insight from the developing embryo to the holobiont and ultimately to Gaia, a living world sustained by interspecies cooperation. The book's chapters revisit fertilization, embryonic development, childbirth, immunity, evolution, and metabolism, challenging familiar accounts that make DNA determinative and treat the organism as a bounded individual. Gilbert shows that bodies are made and maintained through cooperation, and that protecting future life requires protecting the ecological relationships on which all life depends. Gilbert also argues that neither science nor religion can confront climate change alone. Drawing on developmental biology, environmental ethics, and numerous religious traditions, he proposes an alliance rather than a merger. Science can clarify how life depends on fragile relationships, while religion can help turn knowledge into collective action. Both science and religion begin in wonder, and both can nurture the attention, reverence, and moral commitment needed to resist extractive systems. We Are All Lichens connects biology, religion, and multispecies ethics. It asks readers to understand human beings as participants in overlapping communities of life on which our collective survival depends.