The worms begin their life cycle as eggs in the feces of birds. The ants forage on that feces for its mineral content, bringing samples back to their colonies to feed their young. The ant larvae have no defenses against the worm and so the eggs hatch inside them and the worms live out their lives in the end segment—called the gaster—of the ant's body.
This is where the worm's evolutionary sleight of hand comes into play. As the worms lay increasing numbers of eggs, the outer layer of the ant's gaster—which is regularly black—is stretched thin so that it becomes translucent. In the sun, it appears to be a red berry. Birds are then attracted to eat the ants and by consequence consume the worm eggs inside as the entire cycle begins again.
Via NY Times
Five amazing, clean technologies that will set us free, in this month's energy-focused issue. Also: how to build a better bomb detector, the robotic toys that are raising your children, a human catapult, the world's smallest arcade, and much more.