"Cordyceps fungi can decimate entire ant colonies, but some colonies can keep an infestation at bay and survive for long periods of time. A new study now reveals how they do so. It turns out that the zombie-ant fungus is itself parasitized by another fungus, which limits its ability to reproduce and prevents it from overwhelming the colony. This microbial defence system allows the two species to stably co-exist and ensures the long-term survival of the colony despite a high rate of infection.
"The Cordyceps fungi manipulate worker ants to leave their nest and march off to a nearby site where they will eventually meet their fate. These sites are mass graves littered with the bodies of nest-mates that have succumbed to the fungus. They can persist in the same location for years, growing steadily as ants arrive one by one to die.
"Sandra Andersen of the University of Copenhagen and her colleagues took advantage of this. They analysed the growth rate of five graveyards containing ant corpses infected with Ophiocordyceps camponoti-rufipedis, all located within a 400 hectare nature reserve in the Brazilian rain forest.
"They identified a total of 432 infected ants in the five sites, and characterized each one according to the developmental stage of the fungus. This showed that 1/8 of the ants had been freshly killed, and a similar number were somehow damaged and showed no obvious signs of fungal growth. Another 1/8 had an immature mushroom growing from their heads, but only 1/16 had mature mushrooms that produced spores. They also found that more than half of the dead ants in each graveyard harboured a second parasitic fungus."
Ergin Kocyildirim originally shared this post:
This is a bit scary…
Ant colonies are protected against brain-manipulating parasitic fungi by another fungus