National Geographic has some creepy new insights into one of nature’s creepiest reproductive strategies. The zombie ants – insects whose brains have been hijacked by the Ophiocordyceps fungus – are much more strategic in their shambling movements than one might imagine:
It takes about three to nine days from initial infection for the ants to become completely zombified, the team found. At first, the infected ants go about their normal business, residing in their nests, interacting with other ants, and even feeding.
“I think of them then as chimeras: part ant and part fungus,” said study leader David Hughes, an entomologist at Pennsylvania State University.
“As time goes on, the fungal part increases until that ant’s behavior is no longer its own.”
After a few days, the fungus directs the insect to clamp down on a leaf. The multiplying fungal cells in the ant’s head then cause fibers to detach within the muscles that open and close the ant’s mandibles.
Adding a new twist to the tale, the latest research shows that the fungal coup de grace usually occurs at solar noon, when the sun is at its strongest. The fungus might be using sunlight to synchronize the final part of the infection, but this is still speculation, Hughes said.