The meanest kind of plant life is the strangler tree, which comes in several varieties. One example is the strangler fig tree of Brazil, whose fruit provides food for native birds.
Once a bird has eaten a fig, it may fly off with the fig seed in its mouth. It often deposits that seed at the top of a tall tree, where it sprouts. The seed then sends out a double set of roots. One set heads for the ground, as in most plants; the other starts winding around a branch of the host tree.
Once the first set of roots hits the ground, the strangler tree gets stronger and stronger. It develops more and more of the encircling roots and squeezes the host tree’s trunk tighter and tighter.
Finally, the sap can’t flow through the host tree to nourish it, and it dies. But the strangler tree is now strong enough to live on its own, taking the place once occupied by its victim.