Parasitic fungus controls ants

treecutters.jpgPhoto: David Dennis Researchers at Harvard University are studying a parasitic fungus that infects ants, affects their behavior, then sends them to a fungus-friendly death. Here's Ian Sample at The Guardian:
The fungus, which is alive and well in forests today, latches on to carpenter ants as they cross the forest floor before returning to their nests high in the canopy. The fungus grows inside the ants and releases chemicals that affect their behaviour. Some ants leave the colony and wander off to find fresh leaves on their own, while others fall from their tree-top havens on to leaves nearer the ground.
At the end, the infected ant will move under the leaf and latch onto the central vein, an ideal place for fungus to spread. The paper abstract:
Parasites commonly manipulate host behaviour, and among the most dramatic examples are diverse fungi that cause insects to die attached to leaves. This death-grip behaviour functions to place insects in an ideal location for spore dispersal from a dead body following host death.
Fossilized leaves reveal thatOphiocordyceps unilateralis has been up to this since before the Himalayas rose, but scientists say that it's not clear how the fungus controls the ants: "The question now is, what are the triggers that push a parasite not just to kill its host, but to take over its brain and muscles and then kill it." (Pictured above is a Treecutter Ant, which farms leaves to take to their nests, upon which grows the fungus they actually eat) [Guardian via Submitterator. Thanks, Plathypus!]