P-p-p-pick up a parasite

P-p-p-pick up a parasite

Blood-sucking, brain-altering, tongue-eating parasites

What is a parasite?

A parasite is an organism that lives in or on another organism, called the host. The parasite benefits by gaining nutrients at the host's expense. Parasites can make their hosts sick, or even kill them.

Parasites can live on the surface of their host, like the fleas you see on cats and dogs, or inside their host, like tapeworms.

Every non-parasitic species has at least one species that parasitises it. The number of parasitic species greatly exceeds the number of non-parasitic species. Some parasites are more gruesome than others. Here are our top 5 gruesome parasites:

Zombie parasite #1 - the fungus

Ophiocordyceps fungus grows inside insects and gets inside the brain. The fungus causes the infected insect to climb as high as possible. Then, the fungus explodes out of the insect, killing the insect and sending out fungal spores on the breeze to infect the next victim.

The higher the insect climbs, the further the fungal spores can travel. Have a look at this video showing the zombie fungus in action.

Tongue-eating sea louse

Parasitic sea louse

Imagine waking up and instead of a tongue you've got a... parasitic louse! The sea-dwelling parasitic sea louse burrows through the gills of fish. After eating the fish's tongue, the parasite lives inside the fish's mouth and feeds on blood or fish mucus.

Surprisingly, the fish can use the parasite just like a normal tongue and doesn't seem to be damaged in any other way.

Zombie parasite #2 - the worm

Even if you don't like snails, you've got to feel sorry for one infected by a parasitic worm which takes over its brain. When an unsuspecting snail accidentally eats a tiny worm, the worm produces lots of baby worms inside the snail. These baby worms change the snail's eyestalks to look like caterpillars - much more appetizing to birds.

Birds eat the eyestalks, which contain baby parasites and the cycle is complete. Still, the parasitic worm inside the snail isn't done. The snail will probably survive the bird's attack and grow new eyestalks. Unluckily for the snail, more parasites are growing inside its body and will infect its re-grown eyestalks.


Have you seen a giant, parasitic plant that smells like rotting flesh. No, it's no science-fiction. It's a rafflesia! Have a look at this:

Zombie parasite #3 - the wasp

There are lots of species of parasitic wasps, but Glyptapanteles is the most gruesome. The adult wasp lays its eggs inside the body of a caterpillar. Eventually, up to 80 wasp larvae eat their way out of the caterpillar body. They cocoon themselves, waiting to turn in to adult wasps, much like butterflies turn into caterpillars.

With any other species of parasite, this would probably kill the host. Not with this tiny wasp. The parasite has altered the caterpillar's brain so that it stands guard over the wasps, occasionally spinning silk over the cocoons to keep them protected. The caterpillar doesn't even move to eat.

If anything approaches the caterpillar, it thrashes around violently to scare off any potential predators of the wasps. Eventually, the caterpillar dies due to a lack of food. The adult wasps hatch, ready to parasitise another unsuspecting caterpillar.

What about humans?

There are lots of parasites that affect humans. One of the parasites posing the biggest problem to humans is malaria. To find out more about malaria, go to Malaria, one of the world's deadliest diseases.

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