Zombie ants

For more information, teaching aides or to see videos of the zombie ant fungus, go to hugheslab.com or contact dph14@psu.edu.

Your worst fears are real: The South is overrun by zombies.

Zombie ants, that is.

They could be crawling in your backyard right now, possessed by a diabolical force controlling their every thought, a force that is, um, also found in beer.

It's a yeast-like fungus, but not just any fungus. This one gets into a carpenter ant's mind, forces the ant to do its bidding, kills it, then pops out of its head to release more fungus spores for more ants to ingest.

Which is, when you think of it, not really that much different from beer.

Not that there's anything to worry about here.

"After two weeks the ants stagger around. They don't follow their normal paths. They don't respond. If you touch them with a pencil they don't react," said David Hughes, the Penn State University entomology professor who has been studying the fungus.

The ant makes its way to the underside of a leaf it otherwise wouldn't bother with. It bites the stem of the leaf pointed precisely the right way, hanging about 10 inches off the ground - the ideal spot.

"You would see the ant on the twig and the fungus just snaking out of the brain," Hughes said. The fungus then grows a ball of spores it drops to the ground, creating a "killing field" of spores to be picked up by the next ants to wander along.

"The fungus doesn't have a brain, but it controls an animal with a brain. It's really quite impressive," Hughes said.

Impressive? So this stuff has to be pretty rare, doesn't it?

Well, it's a tropical phenomenon that Hughes started studying in Thailand. He became curious to see if he could find it here, then he spotted a photo on the Flickr photo-sharing site - shot near Due West, S.C.

"I was a little bit shocked, because I didn't realize the fungus was here," said citizen scientist Kim Fleming, who shot it. And she's horrified at the thought of zombie ants crawling all around her, right?

"I think it's pretty cool," she said with a laugh. It's the zombie apocalypse.

The fungus, it turns out, is common throughout the South. If you have trees that lose their leaves in the fall, zombie ants could be reeling through your yard right now.

"None of them can infect us," said Brian Scholtens, College of Charleston entomologist. Of thousands of fungi species in the world, only a handful pose any threat at all, he said. Parasites in general are valuable, because they key on predominant species in an ecosystem, helping to protect biodiversity.

"This just happens to be a group that's really specifically evolved to do this one parasitic thing, which is pretty fabulous," Scholtens said.

Fabulous? Fungi? Zombie ant-controlling fungi all around us?

Think of it this way, Hughes said: "Every time you have a glass of beer, your mind is affected by a type of fungus."

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