When you think of zombies, perhaps George A. Romero's film "Night of the Living Dead" or the hit TV show "The Walking Dead" come to mind.
But now there's a new category for mindless eating machines —ants.
A new fungus, known as Ophiocordyceps unilteralis, has been turning ants into actual zombies, causing them to walk mindlessly, eat vegetation and hang from the edges of leaves and twigs. If that wasn't enough, the fungus takes over the ant's body, except for the brain, researchers say.
“Fungal cells were found throughout the host body but not in the brain, implying that behavioral control of the animal body by this microbe occurs peripherally,” according to the study, first published in the journal Proceedings of the National Academy of Scientists. “Additionally, fungal cells invaded host muscle fibers and joined together to form networks that encircled the muscles. These networks may represent a collective foraging behavior of this parasite, which may, in turn, facilitate host manipulation.”
The paper's authors originally believed that the fungus alters the brain to change the behavior of the ants, but it effectively invades the muscle fibers of the ant, creating a sort of skeleton inside the ant.
"The connections are likened to structures that aid in transporting nutrients and organelles in several plant-associated fungi," the paper reads. "These findings alter the current view of parasite-extended phenotypes by demonstrating that behavior control does not require the parasite to physically invade the host brain and that parasite cells may coordinate to change host behavior."
David Hughes, senior author of the work, likened it to "a puppeteer [that] pulls the strings to make a marionette move, the fungus controls the ant’s muscles to manipulate the host’s legs and mandibles.”
After a period of time, the host ant becomes immobilized and the fungus sprouts out of the body and looks for another host to infect – all very reminiscent of zombie movies and TV shows.