Real Life Zombies
It is something right out of a science fiction movie. In the September 2009 issue of The American Naturalist , a study reveals that a tropical fungus invades an ant's body and compels it to do its will. Hijacks it, that is. What's a poor fungus to do? It can only survive in certain temperatures and humidity. It needs to be in a certain location and a certain distance from the ground. The fungus can't just walk there itself and it really does want to survive. So it adapts. How? By turning those little ants into zombies to do their legwork.
No, it's not a B movie plot. The fungus whose scientific name is Ophiocordyceps Unilateralis infects the ants up in their tropical home high in the rainforest trees. Once possessed by the invading spore, the ant leaves kith and kin, bites down hard on a leaf and dies. But like every B movie plot and zombie thriller, there is more horror to come.
When the infected ant leaves its natural habitat, it is compelled to navigate to a specific leaf. Where it ends up to die is no accident. Scientists have found that the fungus correctly manipulates its host to an ideal location for its own growth. The dying ant is sometimes driven a long way during the last hours of its life.
But getting the ant to die where it wants it to is only the beginning. The fungus has found ways to take full advantage of its prized host and has developed methods to keep it intact. As it spreads through the now dead ants body, the fungus turns everything to sugar which implements its growth. It leaves the muscles controlling the ant's mandibles in place to assure the ant's grip on the leaf remains. Should the outer shell of the ant acquire any cracks or crevices, the fungus spreads itself like putty to fill it in and assure a safe and protected environment in which to grow. This zombie-making fungus seems to know what it's doing.
Maybe the Texas ranchers got wind of of what's going on in the tropical rainforests. Plagued by angry fire ants (imported from South America) that devastate ranch land and even swarm and kill newborn calves with their poisonous bites, ranchers took action. They introduced a tiny phorid fly (also from South America) to handle the fire ant problem. The flies swoop on the unsuspecting ant in attack and lays eggs in its body. The hatched larvae proceeds to the ant's brain where it eats it. The now brainless zombie ant wanders around aimlessly for sometimes up to two weeks. The ant's head finally falls off and a new fly emerges to start the process again.
It's ghastly, I know. The worse part is that zombie invasions are not uncommon in the animal world. Certain species of crabs, fish, worms, grasshoppers and more have been hosts. B movies are not so scary, after all.
Other Zombie Creatures
Zombie snail - The flatworm is an invader too. It lays its eggs only to have them eaten by Amber snails. The eggs hatch in the snail's digestive system changing into broodsacs which elongate and invade the snail's tentacles. The broodsacs seek light and the poor snail can no longer retract its tentacles or perceive light. It wanders helplessly into the open attracting the birds which are the flatworm's final destination.
Zombie grasshopper - Another invader is the parasitic hairworm which targets the unsuspecting grasshopper. The grasshopper ingests the hairworm which may live in the corpse of a mosquito. As the hairworm grows, it destroys everything in the grasshopper's brain except for motor function. When the worm reaches adulthood, it uses the grasshopper as a vessel to reach its aquatic mating ground where it compels it to jump into the water and drown. The worm emerges to look for a mate.
Zombie cockroach - The emerald cockroach wasp is a zombie-maker. It stings a large cockroach twice, once to paralyze its front legs and once to remove the escape reflex from its brain. It then steers the docile cockroach to a prepared nest. The wasp lays an egg on the roach's abdomen and leaves it there. When the egg hatches it feeds off the helpless roach. The wasp keeps the roach alive only long enough to use as a cocoon until it reaches adulthood.
Is there really a disease that can make humans turn into zombies? Not that anyone knows about but there are diseases that mimic zombie-like behavior. A couple of these include Sleeping Sickness which is prevalent in Africa and eventually causes victims to fall into a zombie-like state. The rabies virus affects the brain if left untreated causing strange behavior and agitation. They are not the zombies of the Walking Dead but terrifying enough.