Zombies have roamed the Earth for at least 48 million years. Zombie ants, that is. Today, Ophiocordyceps fungi are well known for taking over the minds of ants such as the Camponotus leonardi worker pictured above. Once infected, an ant wanders away from its colony, bites down on a leaf vein near the forest floor, and dies—creating ideal conditions for the fungal fruiting body that sprouts from its corpse. Only parasitized ants perform this routine, and the bite marks they leave are so distinctive that they're recognizable even in fossil foliage, researchers will report online tomorrow in Biology Letters. The ancient leaf pictured bears 29 scars that represent the last acts of up to seven ants, probably close relatives of the modern Camponotus zombies. That makes the leaf the first known fossil evidence of zombie behavior in any animal.
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