The idea of Voodoo mind control turning an “undead” person into a monster was popularized in the movie, “The Night of the Living Dead”. Zombies were the backdrop for Michael Jackson’s music video, “Thriller”. Currently Zombie Tag is a popular pastime on college campuses nationwide. Students are fascinated with zombies and want to know more.
A recent article in PLoS One by Evans, Elliot and Hughes describes four previously undescribed species of the ant fungus, Ophiocordyceps unilateralis. The paper has captured a lot of public attention because of the title: “Hidden Diversity Behind the Zombie-Ant Fungus…..”
“Zombie Ants”! A number of parasites of insects can have profound effects on insect behavior. The parasites can range from worms to fungi to other insects. The “Zombie” tag was first applied to the Cordyceps fungus that attacks species of ants. Cordyceps hyphae invade the body of the ant and consume the internal nutrients. When the nutrients are exhausted, the fungus produces fruiting bodies that grow through the cuticle of the ant.
The infected ants exhibit abnormal behavior. The ants wander away from the nest and perch on foliage at an elevation which is suitable for dispersing the fungal spores. The spores have sharp surfaces that can pierce the cuticle of other ants and continue the infection. Ants infected with the fungus do not behave in the best interest of the ant and its relatives. The ants behave in a manner that benefits the fungus. Thus, biologists have deduced that the fungus is altering the ant behavior.
There are about 400 described species of Cordyceps fungi, although the potential number of species is much higher. Some of the Cordyceps have medicinal properties, including the antibiotic cordycepin and the immunosuppressant cyclosporin.
The 2006 Planet Earth Video (below) discusses Cordyceps, the “Zombie Ant Fungus”.