Mind-bending Body snatchers

The realm of mind altering and body jacking aliens may seem like fiction, but it is a world more anchored in reality than most think. The mostly microscopic world of parasites is not very well known, yet it surrounds us.

From the malarial parasites in mosquitoes to the ever famous flea, parasites are inescapable. Fortunately for us, these parasites aren’t nearly as deadly as the three being presented in this article. These are parasites that are capable of not only stealing bodily resources, but force physical and behavioral change upon their unfortunate victims.

Here are some of the poor unfortunates and their exploiters.

Toxoplasma gondii is a parasite whose ideal environment is in cats, but uses rats as a way to transfer themselves to their preferred host. How it does this is by affecting the normally cautious rat’s brains to make them become more active and careless as to become an easy meal for a passing cat. By altering the rat’s natural behavior, toxoplasma gondii makes an easy transfer to the cat, thus repeating the cycle once the parasite passes out of the cat’s body via its excrement.

Rats can usually detect subtle changes in their environment. It makes them very hard to trap or poison but this parasite overrides the innate response - they almost taunt the cats in a sense.

In rats, the infection is usually contracted from eating cat faeces. The parasite then works itself into every organ in the rat's body especially the brain where it forms dormant cysts. These cysts remain viable for the rat’s entire lifetime, waiting for a cat to come along and eat the aforementioned rodent so the cycle may begin once more.

Now for a more common parasite, the Leucochlorodium paradoxum, a creature commonly seen in the eyestalks of Amber snails.

Amber snails can sometimes be observed to have giant extended eyestalks that seem to have moving lateral stripes. This phenomenon is caused by the Leucochlorodium paradoxum, a species of flatworm. The parasite uses this method to get to its preferred host, birds.

How the parasite gets to the snail is when the bird defecates, the faeces are full of the parasite’s eggs. The snail then ingests the eggs by eating them. Then they hatch inside the snail and infect its main digestive gland where change into cercaries and produce sporocystes, long tubes that can contain several hundred cercaries.

These tubes stretch into the snail’s eyestalks and begin to pulsate. The snail then (in an almost zombie like fashion) climbs up to the highest point it can find and waits.

The colour movement and the enlarge eyestalks attract birds which eat the snail’s eyestalks, thinking they are caterpillars. Inside the bird's digestive tract the cercaries change into the parasite's adult stage, which then reproduces and lays eggs. Those are then scattered by the bird to infect further snails, which closes the generation cycle.

The final body snatcher in our line-up is a parasitic nematode that makes ants look like fruit.

In mid January, scientists discovered a parasite in the forest of Central and South America that causes its host to look like a tantalizing ripe berry. This trick makes birds eat the normally unpalatable ant, and helps the parasite spread. This method of mimicry caused by a parasite is a first in the scientific community.

The researchers suspect the nematodes grow up inside the ants, and then cause the hard outer layer of the gasters (the ant’s hindquarters to you) to thin. When combined with the yellowish coloring of worm eggs, this makes the body segments appear amber. This reflected with sunlight, gives it the appearance of a bright red berry.
As though that were not enough, infected ants tend to hold their infested gasters in an elevated position over the rest of their bodies, as if tempting the birds to come and take a bite. The ants also become sluggish, and the gaster itself weakens, making it easily plucked off by birds. The eggs then pass unharmed through the birds' digestive systems. Ants then eat the bird feces, giving rise to a new generation of parasites in a new population of ants. Be it mind control or physical manipulation, these microscopic creatures will use any method they can to spread to and infest the creatures they inhabit. Lets just say we are fortunate enough that something that’s capable of controlling us has yet to be found and hopefully never will be.

Edit :
Well, since David(Rhomber) has pointed out some things to me I am re-writing this article to be republished later (after I do more research, thanks David!) but I'm leaving the original one here anyway ;)