How the bromeliads got their spines

side A

There was once a certain wicked man, who hated all philosophers and scientists.  He hated them to such a degree that he sat, day after day, in the middle of the busiest part of town, armed with a sharp needle.  Whenever a philosopher passed by, he would stab the point of his weapon into their arms and legs until they ran away, bleeding slightly.

In delight the old sinner continued in this way for many years, until the scientists finally cried out in lamentation: “O deliver us from this persecution! We cannot work because our fingers are bleeding! We cannot research because of the wounds in our legs!”  Apollo hear their supplication and said to the wicked man “Behold, I have heard the cries of the thinkers you torment so much.  Because you have neglected to fill yourself with their wisdom, your mouth will be kept forever open, and will be filled with every rotting thing which falls into it, and this will be your only food forever”.  That instant the wicked man became a Quesnelia arvensis, and remained rooted to the spot.  To this day, scientists who get too close are stabbed.

side B
In a forest there grew a large patch of bromeliads.  They were happy and content, for the trees above them gave them shade, and dropped leaves which the bromeliads were glad to recieve.  Each bromeliad was also filled with a host of tiny helper insects, who broke down the leaves into delicious nutrients for their host.  The bromeliads grew and prospered in peace, until the Ecologists came.
The ecologists wanted the insects inside the bromeliads, but they did not care for the bromeliads themselves.  They stripped plants of their leaves, or plucked them from the earth and shook them upside down.  Sometimes they drained all the water, food and insects from a still-living bromeliad, and other times they tore the unhappy plants completely apart.
The bromeliads were helpless before this new threat, and loudly lamented their ill fortune: “O who shall defend us from these Ecologists?  When will we have our revenge on them?”.  Marsius the satyr overheard their wails, and turning to the bromeliads said “behold, you are not unavenged.  Do you not see how the spines on your leaves draw the blood from the ecologists?  Do you realize that the insects which live in your very leaves grow up to become the biting flies that torment them?  Therefore just as they drain you of your food, you drain their very lifeblood”  And thus the bromeliads were revenged on their tormentors.