Zombifying fungus bypasses the brain to make ants its puppets, study finds

Enlarge / A dead ant that has been taken over by a species of Cordyceps in the Rio Claro Reserve in Colombia. (credit: National Geographic/Justin Maguire)

Pity the poor unsuspecting carpenter ant who unwittingly becomes infected with spores scattered by a parasitic fungus in the Cordyceps genus. The spores attach to the ant and germinate, spreading through the host’s body via long tendrils called mycelia. Cordyceps essentially turns its host into a zombie slave, compelling the ant to climb to the top of the nearest plant and clamp its tiny jaws in a death grip around a leaf or twig.

The fungus then slowly devours the ant, sprouting through its head in one final indignity. Then the bulbous growths on the ends of the mycelia burst, releasing even more spores into the air, to infect even more unsuspecting ants. It’s not a great way to go: the entire process can take four to 14 days.

There are more than 400 different species of Cordyceps fungi, each targeting a particular species of insect, whether it be ants, dragonflies, cockroaches, aphids, or beetles. The zombification aspect has made the fungus a favorite of nature documentaries. It has also worked its way into popular culture, such as the zombie-apocalypse video game, The Last of Us (2013), in which a parasitic fungus mutates so that it also infects humans. But scientists are keen to study Cordyceps to learn more about the origins and intricate mechanisms behind these kinds of pathogen-based diseases.