Zombie Ants

Yeah, though it might sound like a bad straight-to-DVD movie, or even worse, a SyFy original movie (yeah, SyFy, not Scifi–shakes head–sigh); but it seems to be true. And in looking for a picture of ants on google, I stumble across another article on Zombie Ants. So, I’ll post this with a page break, to read the two separate articles on two separate cases of Zombie Ants, click the link for more.

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 the following was found on yahoo.com:

Zombie Ants Controlled by Fungus

LiveScience Staff

LiveScience.com livescience Staff

livescience.com – Wed Aug 12, 9:27 am ET

In a bizarre parasitic death sentence, a fungus turns carpenter ants into the walking dead and gets them to die in a spot that’s perfect for the fungus to grow and reproduce.

Scientists have no clue how the fungus takes control of the brains of ants so effectively. But a new study in the September issue of the American Naturalist reveals an incredible set of strategies that ensue.

The carpenter ants nest high in the canopy of a forest in Thailand, and they trek to the forest floor to forage. The fungus, Ophiocordyceps unilateralis, prefers to end up on the undersides leaves sprouting from the northwest side of plants that grow on the forest floor, the new study showed. That’s where temperature, humidity and sunlight are ideal for the fungus to grow and reproduce and infect more ants.

 Once infected by the fungus, an ant is compelled to climb down from the canopy to the low leaves, where it clamps down with its mandibles just before it dies.

 “The fungus accurately manipulates the infected ants into dying where the parasite prefers to be, by making the ants travel a long way during the last hours of their lives,” said study leader David P. Hughes of Harvard University.

 After the ant dies, the fungus continues to grow inside it. By dissecting victims, Hughes and colleagues found that the parasite converts the ant’s innards into sugars that help the fungus grow. But it leaves the muscles controlling the mandibles intact to make sure the ant keeps its death grip on the leaf.

 The fungus also preserves the ant’s outer shell, growing into cracks and crevices to reinforce weak spots, thereby fashioning a protective coating that keeps microbes and other fungi out.

 “The fungus has evolved a suite of novel strategies to retain possession of its precious resource,” Hughes said.

 After a week or two, spores from the fungus fall to the forest floor, where other ants can be infected.

 Making nests in the forest canopy might be an evolved ant strategy to avoid infection, Hughes figures. The ants also seem to avoid foraging under infected areas. This too might be an adaptive strategy to avoid infection, but more study is needed to confirm it, he said.

 How the fungus controls ant behavior remains unknown. “That is another research area we are actively pursuing right now,” Hughes said.

LiveScience.com chronicles the daily advances and innovations made in science and technology. We take on the misconceptions that often pop up around scientific discoveries and deliver short, provocative explanations with a certain wit and style. Check out our science videos, Trivia & Quizzes and Top 10s. Join our community to debate hot-button issues like stem cells, climate change and evolution. You can also sign up for free newsletters, register for RSS feeds and get cool gadgets at the LiveScience Store.

If that wasn’t creepy enough, I was looking for a pic of “Zombie Ants” and came across this seperate article from National Geographic:

Brain-Controlling Flies to Triumph Over Alien Ants?

May 15, 2009

A decades-long battle against invasive fire ants in the southern U.S. might be turning a corner, thanks to a nightmarish little fly.

(Pictures: “Zombie” Ants Controlled, Decapitated by Flies.)

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Fire ants are widely hated, because they bite people’s feet, kill infant birds, short out electrical units, and outcompete native ant species.

But as punishing as fire ants can be, they’ve got serious competition in parasitic phorid flies.

Plentiful in fire ants’ South American home ranges, phorid fly females inject their eggs into the fire ants.

The egg develops into a maggot, which appears to control the ant’s behavior. The maggot “directs” the ant to a moist, leafy place—phorid larvae are vulnerable to drying out—a safe distance from other fire ants.

The larva then eats the ant’s brains, causes the ant’s head to fall off, then finally “hatches” from the ant’s hollowed-out head about 40 days later.

“Not only is it decapitating it, but it turns the ant into a zombie,” said Sanford Porter, a research entomologist with the U.S. Department of Agriculture’s Agricultural Research Service.

Fighting Fire With Phorids

Since 1997 researchers have been importing and releasing several species of phorid flies in Florida and Texas, one of the hardest-hit areas. Finally, researchers say, the flies are approaching a critical mass and could begin actually to control fire ant populations.

Previously released species attack at ant mounds. But this year scientists are planning new releases of a phorid fly species that attacks fire ants on their foraging trails—,meaning, if all goes well, the fire ants will be vulnerable to phorids both in the mound and on the trail.

“The more [phorid species] we have, the better,” said entomologist Scott Ludwig of the Texas A&M University‘s AgriLife Extension Service and his colleagues.

All-Out War

Rob Plowes, a research associate at the University of Texas, said fire ants first emigrated from Argentina to Mobile, Alabama, in early 1930s, probably on an agricultural-produce boat, then began moving through Texas around 1950.

“They’re still spreading,” Plowes said.

There’s a “huge history of efforts to remove the ants, ranging from physical removal to pesticides and, most recently, biological control,” Plowes added.

Though one phorid species didn’t take hold, two others have expanded to cover almost half the U.S. fire ant range and will probably make it the rest of the way in the next several years, the USDA’s Porter said.

Ludwig and his colleagues released the foraging-ant-attacking species, Pseudacteon obtusus, last year in southern Texas, though the species has failed to spread.

This year the researchers will release P. obtusus in two new locations—one near previously released species in southern Texas so that, hopefully, the different species’ ranges will one day overlap, resulting in a multipronged attack on the ants.

The second set is headed to eastern Texas, where no other phorid flies have yet been released. Eastern Texas is moister than southern Texas, making the east more conducive to phorid survival, the researchers hope.

Besides the phorid flies, several labs are working to develop fire ant-fighting fungi and viruses—perhaps to be delivered via phorid fly eggs.

“It will take a community of natural agents to control them,” Porter said.

At least we know that there are Zombie Ants out there and they are being kept at bay by fungus, flies and scientist…now I can rest easy tonight.

–Cos

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