Though this may strike terror, I should mention there is a medical
mycologist at Michigan State who is studying Pythium. This plant
pathogen has under special conditons, the ability to "jump species"
and infect mammals! It causes a horrible, rapidly lethal disease
in horses, dogs, and humans. Pythiosis results in huge slimy cankers
which kill the host through loss of fluids. I'm sure not all Pythium
species can/will do this, but the one under study lives on grasses
in tropical environments, and tends to infect animals through wounds
when they wade through ponds (where the flagellate zoospore phase of
the fungus can be found). Strangely, the infection phase in mammals is
not part of the life-cycle of the fungus. The infection seems to be a
"mistake" which kills both the fungus and the host. But I suspect this
may be how some disease begin evolution... Fortunately our mycologist
has some good leads on a cure, but the incidence of the disease is so
rare in humans, it has until recently been hard to recognize and
diagnose before the victim succumbs.
Sorry to distract you all with this semi off-topic story. Please
return to kneading your wet Sphagnum. :-)
Michael Chamberland