John Perlin is a lecturer, consultant, and the author of several scientific/historical books including A Forest Journey: Wood and Civilization, published by Harvard University press as one of its "One-Hundred Great Books" and a "Classic in Science and World History." In this episode of Nature Revisited, John takes us back in time to discover how wood was the foundation upon which most societies were built. With wood serving as the basis of metallurgy, ceramics, architecture, the construction of ships and more, civilizations rose and fell because each began with a plentiful forest resource, used it up, and was extinguished – to be succeeded by a newer center, closer to a new rich swathe of forest. By viewing human history in the context of wood as humanity's most essential material, we see that humanity's future relies on renewing our symbiotic relationship with the trees that have sustained us.