River systems are dynamical networks that evolve over time, through erosion and other processes.
Both diseases and rumors are transmitted through social networks, and computer viruses routinely spread through the Internet. Food-webs, ecosystems, and metabolic pathways can be represented by networks, as can the relationships between words in a language, topics in a conversation, or even strategies for solving a problem. Energy is distributed through transportation networks, both in living organisms, man-made infrastructures, and other physical systems. It draws on SFI's expertise in understanding emergent properties of relatively simple systems. What is new is that we are moving beyond simple idealized systems to consider large-scale realistic networks.