Emerald Jewel Wasp

Cockroaches can fall victim to the parasitoid Jewel Wasp (Ampulex compressa), which employs them as live, yet immobile food supply for its larva. Unlike most other parasitoids, this tropical Ampulicine wasp does not simply paralyze its prey to immobilize it. Instead, it stings a cockroach in the head and injects a neurotoxic venom cocktail directly inside the cerebral ganglia. This turns the cockroach, metaphorically, into a submissive ‘zombie’: it gradually enters a long-lasting hypokinetic state, during which it becomes unresponsive to aversive stimuli and fails to self-initiate walking or escape behaviors. Although the stung cockroach is not paralyzed, it allows the wasp to cut both its antennae and drink hemolymph from the cut ends. The wasp then grabs one of the antennal stumps and pulls backwards, leading its prey into a pre-selected nest. The intoxicated cockroach, rather than fighting or fleeing its predator, actually follows the wasp submissively. In doing so it demonstrates a completely normal walking pattern, as if it was a dog led by his Master's leash. The wasp then lays one egg on the cockroach's leg, seals the nest and leaves the lethargic prey inside, still alive but powerless to escape under the influence of the venom. As the wasp larva hatches from the egg, it penetrates through the cockroach's cuticle and feeds on its internal organs for several more days. Only then, roughly five days after the sting, does the cockroach finally die and the larva pupates inside its abdomen, safe from predators outside the nest.