How things get complicated

Pre-biotic evolution created something almost infinitely unlikely to have arisen by chance: reproducing entities whose many parts interact in a way that is vastly more complex and interdependent than the disorganized interactions of the inanimate objects in the surrounding environment. And yet this creation of primitive organisms was all achieved in perhaps a few hundred million years. In the January 16 Proceedings of the National Academy of Sciences, Jain and Krishna use mathematical modeling to propose that this creation event was no freak occurrence, as complexity and stability evolve rapidly and inevitably from interacting systems (Proc Natl Acad Sci USA 2001, 98:543-547). Their model involves a matrix of nodes, where each node could represent a chemical, species or element of human society. The nodes are given arbitrary starting populations, and random connections, with some connections positive (node A causes an increase in the population of node B)...