The nematode parasite (Myrmeconema neotropicum) manages to turn Cephalotes atratus ants’ gasters (enlarged part of the abdomen) the color of local red berries—the kind that birds eat—and also impel the false berry-baring hosts to venture away from the colony, making them easier prey. When the exposed victim is snatched up by a bird, the latter is infected with the parasite. After the bird digests its tainted treat, it passes along the parasite passenger in its droppings, which stand waiting to infect other unsuspecting ants.

] Zombie Creatures: What Happens When Animals Are Possessed by a Parasitic Puppet Master