Real zombies found in nature
Fungus grows out of the head of an ant.
November 30th, 2012
07:30 AM ET

Real zombies found in nature

By Elizabeth Landau, CNN

Zombies are everywhere, from hit TV shows like "The Walking Dead" to films like the upcoming "Warm Bodies." We seem fascinated by these ghastly creatures who are infected with an unknown disease that compels them to gurgle or groan and lust after brains.

These zombies are, of course, fictional. But the idea that a parasite can infect and control animals is real. There are several examples in nature where parasites manipulate host behavior to further their own reproductive goals. It's fascinating to think about how, when one organism invades another, the host can lose power over its own movements and behaviors.

David Hughes, assistant professor of entomology and biology at Pennsylvania State University, studies real-life zombie scenarios among ants.

He points out that half of all of life on Earth is parasitic, but it’s rare for the parasite to be able to take the steering wheel inside its host. Often, parasites just lead to sickness – like malaria in humans – or annoying bites, as with bedbugs.

“Every single organism that we look at has its own parasite, but only a small proportion of them have evolved this cruel trick of manipulating the behavior of the host that they’re infecting,” he said.

Parasites can live in the brain or muscle tissues and can lead to some crazy behaviors.

One source of parasites that Hughes studies is called Ophiocordyceps, a group of fungi. The spores that the fungus releases attach to the skin of carpenter ants, which Hughes and colleagues observed in Thailand. It takes about 12 to 18 hours for the fungal spore to grow into an ant’s skin.

You should first know a little something about ants: There’s a queen who does all the egg-laying and other females, called workers, who collect resources for the colony. As one of these workers is walking through the forest, she can contract fungal spores that infect her and ultimately control her behavior.

As a result of the fungus, the ant leaves the nest and has convulsive behaviors. She may be “walking randomly around the forest for a couple of hours,” Hughes said.

And then, the ant will go to the underside of a leaf, bite into the veins and hang upside down to die for about six hours. "The fungus makes them hold on (to the leaf) even after they’re dead,” Hughes said. From the head of the ant corpse sprouts more fungus, which emits spores, infecting more ants.

Hughes and colleagues also observed this phenomenon in Brazil.

Check out this video about Hughes' research from Penn State:

Lest you think this is the beginning of a new zombie invasion, Hughes and colleagues have found evidence of this happening in ants about 48 million years ago in Germany. The process has survived many generations.

This isn’t the only instance of parasites manipulating their hosts’ behavior. Gordian worms, also called horsehair worms, can live in crickets’ bodies for a long time.

Here's a demonstration from VB Films:

These parasites cause changes in protein expressions in the brain that make the cricket quite thirsty. The cricket, possessed, heads to a pool of water where it dies, but the worm exits to mate with other members of its species.

Rats also exhibit self-destructive behaviors when invaded by parasites. Toxoplasma makes rats lose their fear of cats, so they may not run away when a cat tries to eat them. That’s what the parasite wants: for the cat to eat the rat so that Toxoplasma can pass into the cat, too.

Even we humans may not be immune to the behavioral influences of parasites. Toxoplasma also infects humans, at much higher rates in some countries than others, and some researchers are looking into whether that could affect personality.

According to the Centers for Disease Control and Prevention, more than 60 million Americans are carrying the Toxoplasma parasite. In most people, there are no symptoms because the human immune system usually stops the parasite from causing illness.

But Toxoplasma infection can create problems in a small number of cases, especially in pregnant women - who can pass the parasitic infection to their children, causing blindness or mental disabilities later in life - or people with compromised immune systems. Cats can play a role in the transmission of Toxoplasma through feces. That's why those people are advised to keep their cats indoors and to avoid changing cat litter and touching stray cats.

This parasite may be affecting us in ways we do not realize. Kevin Lafferty of the University of California, Santa Barbara, has done some highly controversial work suggesting that certain cultural-personality traits such as neuroticism may be correlated with levels of Toxoplasma gondii. He suggest that countries with higher infection levels may be more likely to have stronger "masculine sex roles" in their societies, insofar as they "reinforce traditional gender work roles, gender differentiation, and have a higher focus on ego, ambition, money, material possessions, self-achievement and work than on relationships, people, social support and quality of life."

Science writer Ed Yong also postulates that there could be some interaction with climate. Toxoplasma gondii eggs have a longer lifespan in “humid, low regions.” Parasites, climate and culture may all interrelate.

Of course, just because there are associations between the parasite and behavioral traits does not mean that one causes the other. Obviously, a lot of factors influence human cultural patterns.

If there is any credence to the notion that parasites are influencing culture, that would mean many of us are, in some sense, part zombie.

Regardless, it’s fascinating to think that the creepy mind-control stuff of the movies is actually happening to some extent in nature, even in the unsuspecting world of ants.

More from CNN: Chain of cat feces can harm humans, sea otters

Post by:
Filed under: On Earth
soundoff (30 Responses)
  1. Delphia Pizzo

    Television programming started out as transferred radio variety shows to television. Shows such as Texaco Star Theater got their start on radio and was one of the first US television hits in the late 1940s.^

    The latest short article coming from our web portal
    <="http://www.caramoantourpackage.com

    April 14, 2013 at 9:50 pm |
  2. michael kors tortoise watch

    Nowadays, michael kors bags are becoming a really stylish accent being noticed together with. They may be a really iconic layout and lots of superstars pick michael kors hand bags since there's a fantastic bag selection. In case you are seeking to buy an extremely stylish and also attractive bag next you should think of the fantastic array of michael kors hand bags being offered. You can find numerous fantastic models to pick from you will be pampered regarding selection. michael kors bags and also components are notable for their particular huge striking michael kors emblem published to them. This kind of tends to make these quickly recognisable and the ones can realize you might have dedicated to a fantastic top quality merchandise. michael kors tortoise watch http://www.michaelkorsbagss.net/michael-kors-tortoise-watch.html

    March 13, 2013 at 12:02 am |
  3. zlop

    iZombies - Sports Zombies - TV Zombies - Vaccination caused Zombies
    "Zombie Virus Is REAL Develop By NATO" uTube

    December 19, 2012 at 12:38 am |
  4. Truth Gut Punch

    There are human zombies. They're called obama voters and are controlled by "free" goodies.

    December 14, 2012 at 9:55 am |
    • amadeus

      There are no zombies. There are trolls.

      December 15, 2012 at 4:49 pm |
    • Paul

      Never miss a beat, do you? You lost. Put some mustard on that and eat it.

      December 20, 2012 at 4:39 pm |
    • tron

      Also known as porch zombies, allways wanting some sort of handout.

      December 21, 2012 at 1:03 pm |
  5. redman

    Reannimated corpse or mutated infectious virus.

    December 9, 2012 at 9:50 pm |
  6. jimboloko

    This fungus (mutated and affecting humans) is at the core of "The Last of Us" coming out for the PS3 during Spring 2013. Looks intense. Check it out.

    December 8, 2012 at 4:32 pm |
  7. moose1

    Remember rule number two: Double Tap!!!

    Two shots to the head to kill zombies!!

    December 7, 2012 at 7:45 pm |
  8. tj

    i haven't been for 20 years

    December 7, 2012 at 2:13 pm |
  9. ...

    I find this fascinating... These literally are zombies...

    December 6, 2012 at 8:27 pm |
  10. NJStylee

    "There are several examples in nature where parasites manipulate host behavior to further their own reproductive goals. It's fascinating to think about how, when one organism invades another, the host can lose power over its own movements and behaviors."

    Oh, you mean like Obama supporters?

    December 6, 2012 at 3:55 pm |
    • Rennac25

      NJ=New Jersey, who's governor essentially backstabbed Romney and endorsed Obama?

      Stupidity at it's finest.

      December 10, 2012 at 3:54 pm |
  11. piranha

    Yartsa Gunbu or Yatsa Gunbu (Parasitic caterpillar fungus) ~ VERY WEIRD! But it had a royal purpose.

    December 4, 2012 at 5:20 pm |
  12. Jorge

    You don't have to go to the animal kingdom to find real-life zombies. The U.S. is infested with them, slogging bodies whose brains have been taken over by the spirits of Nathan Bedford Forrest, Joe McCarthy and Louis Farrakhan...

    December 4, 2012 at 9:55 am |
    • jer

      Ibet you dont even live in the US and if you do you are hiding behind your keyboard and not enjoying the real world

      December 5, 2012 at 11:04 am |
    • tron

      You forgot Jesse Jackson and Al Sharpton.

      December 21, 2012 at 1:05 pm |
  13. cpc65

    There's a type or microscopic parasite the infects tree snails and takes over their brains. Normally the snail stays on the underside of leaves and branches, but the parasite makes it go topside. It's whole head then pulsates, thus increasing the chance that a bird will eat it. The parasite thrives and reproduces in the bird's stomach, and eventually more parasites end up in the bird's poo. More snails eat the bird poo and the cycle starts anew.

    December 3, 2012 at 6:48 pm |
  14. Joe

    These aren't zombies, zombies aren't controled by parasties. It's usualy a virus that eats your brain and then mutates whats left and reanimates you.

    December 1, 2012 at 11:27 am |
    • fimeilleur

      And that virus, by definition, would be a parasite... Def: an organism that lives on or in an organism of another species, known as the host, from the body of which it obtains nutriment.

      December 3, 2012 at 11:22 am |
      • Joe

        Yes, but it also requires the host to be alive.

        December 3, 2012 at 12:53 pm |
      • fimeilleur

        Considering the zombies you're refering to are only written about in science-fiction novels, and/or scripts... I find it funny that you are arguing semantics over the hypothetical nature of the infected person's condition. These zombie ants, are alive until they grip the leaf and then die, allowing the fungi to reproduce and infect other hosts.

        December 3, 2012 at 1:14 pm |
  15. Bendeus

    What happens to the ants is pretty horrifying when you think about it! Just imagine if that happened to PEOPLE... It reminds me of the Flood in Halo.

    December 1, 2012 at 11:11 am |
  16. rocket surgeon

    *had a plan to -

    November 30, 2012 at 10:06 am |
  17. rocket surgeon

    Forget this, just found out the us had to n uke the moon during cold w ar...w t f

    November 30, 2012 at 9:57 am |
    • Wow

      Hahahahah the US never launched a nuke at the moon. Reread the article on it, buddy.

      December 9, 2012 at 3:47 pm |

Contributors

  • Elizabeth LandauElizabeth Landau
    Writer/Producer
  • Sophia DengoSophia Dengo
    Senior Designer