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Spiders are by no means the only creatures that need to fear the parasitic wasps’ coercive tactics. And drugs are not the wasps’ only weapons for gaining the compliance of their victims. Ampulex compressa, better known as the jewel wasp because of its iridescent blue-green sheen, performs neurosurgery to achieve its aims. Its quarry is the annoyingly familiar American cockroach (Periplaneta americana). Not to be confused with the comparatively diminutive German roach common up north, this species prefers warmer climes and can grow as big as a mouse. Though dwarfed in stature by its prey, a female jewel wasp that has caught the scent of an American roach will aggressively pursue and attack it—even if that means following the fleeing insect into a house. The roach puts up a mighty struggle, flailing its legs and tucking in its head to fend off the attack, but usually to no avail. With lightning speed, the wasp stings the roach’s midsection, injecting an agent that will temporarily paralyze it so that the behemoth will stay still for the delicate procedure to follow. Like an evil doctor wielding a syringe, she again inserts her stinger, this time into the roach’s brain, and gingerly moves it around for half a minute or so until she finds exactly the right spot, whereupon she injects a venom. Shortly thereafter, the paralytic agent delivered by the first sting wears off. In spite of having full use of its limbs and the same ability to sense its surroundings as any normal roach, it’s strangely submissive. The venom, according to Frederic Libersat, a neuroethologist at Ben-Gurion University in Israel, has turned the roach into a “zombie” that will henceforth take its orders from the wasp and willingly tolerate her abuse. Indeed, the roach doesn’t protest in the least when she twists off part of one of its antennae with her powerful mandible and proceeds to suck the liquid oozing from it like soda from a straw. The wasp then does the same thing to its other antenna and, assured that the roach will go nowhere, leaves it alone for about twenty minutes as she searches for a burrow where she’ll lay an egg to be nourished by the roach. Meanwhile, her brainwashed slave busies itself grooming—picking fungal spores, tiny worms, and other parasites off itself—providing a sterile surface for the wasp to glue its egg. When the wasp returns, she seizes the roach by the stump of one of its antennae and “walks it like a dog on a leash to her burrow,” said Libersat. Thanks to its cooperation, she doesn’t have to waste energy dragging the massive roach. Equally important, he said, she doesn’t “need to paralyze all the respiratory system, so the thing will stay alive and fresh. Her larvae need to feed five or six days on this fresh meat, which you don’t want to rot.” The
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Kathleen McAuliffe (This Is Your Brain On Parasites: How Tiny Creatures Manipulate Our Behavior and Shape Society)