  The economical world consists of a highly interconnected and interdependent
network of firms. Here we develop temporal and structural network tools to
analyze the state of the economy. Our analysis indicates that a strong
clustering can be a warning sign. Reduction in diversity, which was an
essential aspect of the dynamics surrounding the crash in 2008, is seen as a
key emergent feature arising naturally from the evolutionary and adaptive
dynamics inherent to the financial markets. Similarly, collusion amongst
construction firms in a number of regions in Japan in the 2000s can be
identified with the formation of clusters of anomalous highly connected
companies.
