ABSTRACT
Though they lack the metabolic diversity of bacteria, fungi make large contributions to the global carbon cycle. Hyphal organization combines the ability to assimilate nutrients along a distributed network with the capacity to focus extracellular enzyme release at growing tips (Frey et al., 2000, 2003). As a result, fungi are more efficient than bacteria at colonizing and breaking down large detritial particles. Fungi also carry more genetic information. Despite these advantages, the decomposition of organic matter remains a community process. No population can express the range of enzymes needed to degrade complex substrates, such as cell walls (Osono and Takeda, 2002). It is somewhat paradoxical that decomposition is a collective enterprise while fungal community structure and succession appear to organized by competitive, often antagonistic, interactions (Gulis and Suberkropp, 2003; Mille-Lindblom and Tranvik, 2003; Thormann et al., 2003). This paradox is more striking in light of emerging evidence that heterotrophic bacteria make extensive use of signal molecules to coordinate gene expression within and between populations, a phenomenon known as quorum sensing (Manefield and Turner, 2002; Burmolle et al., 2003; Nakayama et al., 2003).
