Zombies Are Real!

This ant didn’t grow a horn. That long stalk is part of a parasitic fungus that grew inside the ant.

First, a tiny fungus called a spore lands on the ant. The spore burrows through the insect’s hard outer shell. Then the fungus multiplies inside the ant’s body.

Scientists think the fungus releases substances that control the insect’s behavior. The ant is forced to bite down on a branch, clamping itself in place. This isn’t for the ant’s benefit. It’s the perfect spot for the fungus to find its next victim.

Within hours, the ant dies. After a few days, the fungus bursts out of the insect’s body and releases a shower of spores. That’s bad news for any ants crawling below that could become the parasite’s next hosts.

These garden snails are victims of a parasitic flatworm. This happens when a snail eats bird poop with flatworm eggs inside. Baby flatworms hatch and creep into the snail’s brain. Then they invade its eyes. The parasites make the snail’s eyes look like wiggly caterpillars—a nice snack for birds.

Snails usually avoid well-lit locations, where predators can easily spot them. But zombie snails move out into the open. Scientists think that’s because the parasites release a chemical that changes how the snails behave.

Birds see the tasty-looking eye stalks and bite them off the snail. The flatworms infect the birds, and the cycle begins again. But for the snail, the worst is over—its eyes grow back!

This grasshopper met a gruesome end: It died when a long, wriggly worm burst from its body!

Horsehair worms live in water. A female worm releases millions of eggs. Then larvae hatch from the eggs. An insect, like a grasshopper, may eat one of the larvae while drinking the water. The parasite then grows inside the host. Once it’s grown, the worm releases a substance that makes the grasshopper do something it normally wouldn’t: go for a swim.

Once in the water, the worm bursts out of the insect within seconds. Then the worm starts the cycle again.