The poison in a mushroom does it no good. 
It doesn’t know, nor does the fellow who eats it,
but he will find out.  And maybe he will tell
others about the mushroom and even describe it,
a Death Cap, say.  Others of that species
are beneficiaries, and others also,
because people will hesitate unless

they know exactly what they are doing.  The death
of the one (mushroom, I mean, not the man)
may save the others.  And what greater love
than to lay down one’s life to save another?
Or, no, that’s not necessary; take into account
the sweet revenge the mushroom anticipates
jouncing along in the basket.  Destroying Angels

could take the same satisfaction—but that is assuming
mushrooms can think and are self-aware.  Unlikely,
so we are forced to look up to a practical-joker
God who, having thought of this intricate business,
couldn’t resist.  Mushrooms seldom laugh
but He does, often, at his own cruel jokes.