Researchers from specialties as diverse as mathematics, climatology, and neuroscience have come to understand the natural world as a complex of different systems continually interacting with each other. They have identified universal features of these dynamical systems that remain valid across the entire natural world, from systems as vast as global climate to as small as a living cell. A common feature of these systems is that they self-organize to create a cohesive whole that cannot be completely understood by reducing the system to its elemental parts.