There are many films, games, books and comics that feature zombies. As we watching those films or reading the books, we know that they are not real, there won’t be a zombie apocalypse. And if it does, we know for sure what we should do to kill [side question: How to kill something, that is already dead?🤔] them from the games. It may sound absurd, but there are zombies out there in the wilderness, but not this type:
If we want to find the living dead, we need to search among a bit tinier creatures, precisely among ants. But how can a clueless ant become a zombie ant? Well, the answer may sound familiar if you watched The Last of Us:
Fungus
More specifically Ophiocordyceps unilateralis. Several fungi belong to this group and they can turn insects into zombies. But don’t worry, these zombie-making creatures are specific to Camponotini species, so the humans (and other insects) are safe. And if somebody still afraid of them, keep calm, they can be found in tropical regions.
How does the process works?
I bet you think about how can a fungus turn an ant into a zombie? Well, it is a very interesting method. First things first, an unsuspicious ant needed, which picks up the spores of the fungus. The spores than start to grow, and secretes different enzymes (chitinase, lipase, protease) to degrade the exoskeleton of the ant. As the enzymes breaks down and weaken the exoskeleton, the spore can break through the weakened points, and get inside the ant.
The fungal cells that are inside the host migrate to the “brain”, and start to proliferate. The location is crucial, because the fungus secrete neurotoxins and secondary metabolites [1] (guanidinobutyric acid, sphingosine) that alter the host brain function such a way that it climb up a leaf and bites the lower part of a leaf. Beside the “brain”, fungal cells can be found in the mandibular muscle [2] which “help” the ant to bite the leaf, and never it go, this is why it called the ‘death-grip’.
After the ant is in place, preferably near and above the colony, the fungus can grow out of the ant, form a fruiting body, and than spreads its spores and the cycle starts again.
It is like a shapeshifter alien and a spaceship. the alien hold on to the ship, and through the little gaps of the cover it gets inside. Then it tries to hide and sneaks up to the cockpit, and takes over the ship.
Can humans turn ants into zombies?
There were scientific experiments, where scientists tried to inject those chemicals into ants, that are secreted by the fungus, but there was no difference in the behavior of the ants, which suggests that it is far more complex mechanism and the presence of the fungus is needed to create a zombie.
Furthermore the ants are not living on the forrest floor, but in the high canopy. There is a complex network of trails from leaves to leaves with smaller or larger gaps the ants have to cope with. Sometimes it fails, and one or 2 ants fall to the forrest floor, or the distance is so big that they don’t even try it, they straight descend to the floor. That’s when the fungus has a chance. Moreover the infected ant tries to get as far from the colony as possible, before the fungus takes over the control. Even though it is a bit hard for the fungus to infect a host, it looks bizarre and really resemble a zombie.
Additional informations
The O. cordiceps was discoverd in 1859 by Alfred Russel Wallace who was an English scientist and the contemporary of Charles Darwin. The process of the host alteration takes four to even ten days from infection to the release of the spores. The O. unilateralis represents 24 species, all of them specific to Camponotini ants [3].
If you want to learn more about the zombie-fungus:
- Species-specific ant brain manipulation by a specialized fungal parasite
- Ophiocordyceps unilateralis
- Graveyards on the Move: The Spatio-Temporal Distribution of Dead Ophiocordyceps-Infected Ants
What are your thoughts on this? Have you heard about this fungus before? Leave a comment and follow me for similar posts on instagram and X!
Glossary
- secondary metabolite: small molecule produced by an organism, that are not essential for their growth, development and reproduction.
- mandible: The “jaws” of the ants, the mandibular muscle is the muscle that moves them.
- Camponotini ants: Is a tribe in the Formicidae (Ants) family.