If you want to invade and dominate the thoughts of another living being, you better have a psychic helmet or a fedora, because mind control is the realm of science fiction and ill-advised dating manuals. It's pure fantasy ... at least, for humans. Nature has had mind control on lockdown for millennia. We've tried to warn you about the impending threat of nature's psychic warriors before, but you didn't listen. You must heed our words this time, for -- shh, they grow closer! No. No! We thought we had more time! Quick, flee and tell the world! Tell them about ...
The Euhaplorchis californiensis is a trematode, or a fluke (if you're nasty). These parasites reproduce only inside the belly of a bird, but since they live underwater and are all but microscopic, that's kind of a tall task. Enter the California killifish, who lives up to its name by being killed in one of the worst ways imaginable -- via parasitic fluke eating away at its brain until it mindlessly offers itself to a hungry avian.
"You should have stayed in school."
The trematode infiltrates the killifish and sets up camp in the brain. But one fluke isn't enough to turn a killifish into a mindless zombie -- for that, it needs an army of thousands. Thousands of murderous, brain-altering parasites. It's like the headquarters of TMZ up in this poor fish's head.
As the flukes set up shop in the fish's brain-meat, they form cysts. This actually affects very little, since it's not like the fish was solving complex physics problems or anything. It's a damn fish. It continues on with life as usual, eating and reproducing, unaware that the trematodes have tweaked one vital behavior that will almost certainly end up killing it.
University of California, Santa Barbara
It hits the killifish kill switch, located just southwest of the worm detector.
See, the trematodes' first act of mind control is to regulate the fish's serotonin and dopamine levels, giving it no reason to swim away when there's danger afoot. Next up, the part of the brain responsible for locomotion is ramped up to an absurd degree, forcing the fish into wild herky-jerky movements that attract a lot of attention from a lot of predators. The killifish swim near the surface, rendered unaware of danger by the fluke's chemical cocktail, where they execute a series of attention-grabbing turns and are devoured by predatory birds. The trematodes get their new home, the bird gets an easy meal, and the fish gets to go fuck itself. Hey, nature is a competition. There's always a last place.
Pseudacteon is a type of phorid fly whose means of procreation are somehow more horrifying than its already ominous-sounding name portends. Fire ants, nature's screaming middle finger to humanity's ankles, are instinctively scared of the flies. Imagine! Mere flies, terrifying the mighty fire ant -- that's like finding out the Balrog is scared of ladybugs. But the ants have good reason: Pseudacteon is a mind-controlling parasite that preys exclusively on the fire ant. Once this fly shows up on the scene, instinctual fear kicks in and sends the fire ants running for cover.
Barely stopping to kill and devour even one victim on the way.
Only one problem: Pseudacteon finds fear ... erotic. The flies do their fly-nasty, the females get pregnant, and the couple celebrates by planting the newest member of their family straight into a nearby ant's thorax.
Once inside, the larva slowly eats its way from the thorax to the head, then, as a dessert course, Pseudacteon eats the ant's goddamn brain. The brainless ant then stumbles about, continuing to live for a time, but with no will of its own. Yes, this is a zombie-making parasite with a literal hunger for brains. You go ahead and tell Pseudacteon it's a cliche -- we'll be waiting behind the couch to see how that works out for you. Eventually, the larva grows weary of mocking the corpses of its victims and devours the membrane that keeps the ant's head attached to its body, decapitating the poor creature.
"At least our relationship ended on a clean break."
It uses the hollowed-out skull of the ant as a macabre sort of crib, until it grows too large, and then ...
Ah, the miracle of childbirth.
Despite being both poisonous and carnivorous, we all love ladybugs because bright colors, polka-dots and roly-polyness knock off about 20 IQ points each. The parasitic wasp Dinocampus coccinellae, however, looks at the adorable wittle wadybug and sees only a clubhouse for its children. Just gotta get rid of those pesky organs to make room for a rope-swing.
"It's cramped, but the last owner put a helluva paint job on it."
When it's time for a female to lay her single egg, she does so inside an unsuspecting ladybug, and then flies away, off to continue making the world just a little bit worse simply by existing, as is the prerogative of all wasps. The wasp larva then begins to feed directly off of the ladybug's nutrients and body fat, until it's big and strong enough to completely immobilize its host. It does so by destroying the nerves that control the ladybug's legs, paralyzing it but not killing it. Death is a mercy that nature just does not have time for.
The larva then burrows out of the ladybug's rear and spins a cocoon for itself underneath the ladybug's now-useless legs. The ladybug's bright color (remember: poisonous) acts as a deterrent to any possible predators, thereby keeping its tormenter safe and sound. The ladybug has, in effect, become little more than an immobile fortress -- a living, self-aware, completely petrified Technodrome.
Mathieu Belanger Morin
"Kuhll muh ... Kuhll muh ..."
Once it's time to leave the nest, the wasp flies away without even so much as a "sorry about your gaping anus," and goes off in search of another ladybug to murder by birth. (This wasp can procreate within an hour of birth, because life is not a miracle; it is a process of repeating damnation.)