At the end of a rough year, losing two of our greatest naturalists, Tom Lovejoy and then Ed Wilson the next day, seems pretty unfair. Both of them produced science that remains important. A thread. Biogeography was largely a descriptive field before Robert MacArthur and Wilson created the Equilibrium Theory. It has been fashionable to beat up on its assumptions. But that misses the point. It was a new way of looking at the world that remains fundamental.