White rot, anyway (brown rot is another story). According to a paper in the March issue of Science, it started about 300 million years ago, when certain fungi figured out how to digest the lignin in woody plants.
Until the end of the Carboniferous era (360-300 million years ago), much of the material in wood was indigestible; so, the stuff just piled up, and eventually turned into coal. The usual explanation for the huge buildup of carbon in the Permo-Carboniferous is that anoxic conditions (like those we find in bogs) prevented decay. However, researchers have analyzed the genetics of 31 fungi and worked out the date at which organisms capable of breaking down lignin (the types of Agaricomycetes that produce white rot) first evolved. The date coincides suggestively with the end of the Carboniferous:
Anyway, it's something to think about, as you slop CPES over your boat.Molecular clock analyses suggest that the origin of lignin degradation might have coincided with the sharp decrease in the rate of organic carbon burial around the end of the Carboniferous period.