'the truth must dazzle gradually
else every man be blind' Emily Dickinson
Hypothesis: the ability of predatory fungi to capture and consume nematodes is a secondary function. These 'predators' are principally wood decay fungi that have 'learned' to capture nematodes as a nitrogen source in nitrogen limiting habitats.
Expanding on this: evidence supports that a host of wood decay fungi are not sabrobes but are facultative parasites and have evolved a variety ways to locate and attack all kinds of microscopic life forms including bacteria and other fungi. Nematodes are merely the spectacular tip of this biological iceberg.
Much of our world is littered with a layer of plant and woody debris composed largely of cellulose and lignified cellulose. Fungi are the degraders par excellence of this organic stuff. It is generally believed that these decay fungi are sabrobes, living strictly off the dead organic remains of plants. Some years ago I challenged this generalization and wrote in support of the hypothesis that many, if not most, decay fungi are not the benign saprobes we thought but are in fact aggressive parasites. These fungi have a Jekyll and Hyde existence in which they carry on an apparently benign existence as cellulose degraders while at the same time they have the ability to mount aggressive attacks and destroy and consume other living organisms for essential nutrients. Carnivorous wood-decay mushrooms, that capture, kill and digest nematodes, are the classical example of this remarkable life style, but predation by wood decay fungi is by no means restricted to nematodes and includes other fungi, algae, bacteria etc.
I was invited to write an article on this topic for the journal ' BIODIVERSITY '. This also gave me the opportunity to beat the drums one more time about the importance of fungi in the forest ecosystem. This role has been seriously underestimated, misunderstood or downplayed, at both the professional and popular level, by most of the people (other than mycologists!) who write about these things.
NOTA BENE: My article was originally scheduled for release in the November 2002 issue of Biodiversity and I timed my November 'special' to coincide with this release. Unfortuanetly my article is being moved forward to the next issue (February 2003). It was 'bumped' because of a lengthier than expected article on Diptera. Bumped for a fly!!! How bad can things get?
So as not to pre-empt the article in Biodiversity, the illustrations and the story attached will be delayed until February 2003. SORRY!!!
UPDATE: Click here for updated version February 2003.