THE Dicroceolium Trematode PARASITE has the most bizarre life-cycle imaginable.
This is the wonder that got me started collecting cool life forms.
This parasite lives in the intestine of a bird. When it reproduces, the offspring need to spread out by getting into other birds. So:
1) It lays eggs which are excreted by the bird.
2) The eggs are eaten by snails and they hatch into larvae.
3) The larvae take over the snail’s behavior so that it stays out in the open after dark, rather than hiding under leaves or brush as snails usually do.
4) To ensure the snail gets seen, the larvae invade an eyestalk, making the snail’s tentacle pulsate like a green neon sign, telling hungry birds, “Here I am, eat me.”
5) Like magic, it’s back inside another bird’s intestines.
Clearly, nature has a sense of humor.