6.9 billion tons of coal was produced in 2009, according to the International Energy Agency
(image courtesy of the USGS and the Mineral Information Institute)
Much of the world’s coal was generated 300-360 million years ago, during an era known as the Carboniferous period. But it may have come to an end from an unlikely source: fungus. An international team of scientists, including researchers at Clark University and the U.S. Department of Energy Joint Genome Institute (DOE JGI), has proposed that a new species of fungus broke down dead plant matter, the source for coal.
The evidence, presented online in the June 29 edition of the journal Science, suggests that the evolution of fungi capable of breaking down the polymer lignin, put an end to an era. Instead of accumulating as peat, which eventually was transformed into coal, the great bulk of plant biomass decayed and was released into the atmosphere as carbon dioxide.
The comprehensive study compared the complete genomes of dozens of species of fungi, most of which were sequenced at the DOE JGI.