Fungus turns ants into zombies

A foraging ant. Millions of years ago, a fungus evolved, which infected ants, making them lock their mandibles in a “death grip” around the central vein, immobilising themselves and locking the fungus in position. File photo

The oldest evidence of a fungus that turns ants into zombies and makes them stagger to their death has been uncovered by scientists. The gruesome hallmark of the fungus's handiwork was found on the leaves of plants that grew in Messel, near Darmstadt in Germany, 48million years ago.

According to the findings, parasitic fungi evolved the ability to control the creatures they infect in the distant past, even before the rise of the Himalayas.

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.

It then 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.

Infected ants move towards the underside of the leaf they are on and lock their mandibles in a “death grip” around the central vein, immobilising themselves and locking the fungus in position. One can find graveyards with 20 or 30 ants in a square metre.

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