The last moments of this cricket’s life were strange. It shakily climbed up a tree, stopped on a leaf, shuddered, went still, and died. Over the next few weeks, thin stalks started growing from its body. The stalks belonged to a deadly, mind-controlling fungus, which caused the insect’s untimely end.
Cordyceps is a genus of fungus that is a parasite—an organism that lives on or inside the body of a host organism, harming it. It’s called “zombie fungus” because of the way it invades insects’ brains, altering their behavior.
The fungi release spores into the environment to reproduce. When one of these tiny particles lands on an unsuspecting insect, the spore grows, working its way into the insect’s body. The fungus spreads, releasing digestive chemicals that slowly break down the insect from the inside out, explains Scott Baker. He’s a mycologist—a scientist who studies fungi—at the Pacific Northwest National Laboratory in Washington State. Eventually, the fungus sends chemicals to the insect’s brain, directing it to climb to a high location. Then it dies. A few days later, the stalks sprout from its corpse. These stalks burst, releasing millions of spores high up in the air to infect insects below—starting the cycle again.
Don’t worry: Cordyceps doesn’t harm people. Certain fungi can make us sick—but none are known to take over our brains. Common fungal infections are mild and usually involve the skin, like itchy athlete’s foot.