If we consider the word ‘zombified’, a range of images come to mind. There’s an immediate thought of the stumbling, brainless creatures from pop culture, followed by more implicit imagery from worlds such as George Orwell’s 1984 – humans as a mindless race, no longer able to think independently. Zombies are linked to this concept of a loss of independent thought, or ‘mind-control’, and though they have been repeatedly portrayed in our books, movies, and TV, we have never encountered them in real life… Or have we?
Meet the jewel wasp – an insect that can literally zombify a cockroach by controlling its mind so that her babies can eat it from the inside out – and I’ll remind you that these really do exist on Earth today.
When a female is ready to lay her eggs, she begins her search for the perfect cockroach host. Once she has located one, the wasp initiates a two-stage attack: First, she clamps her mandibles around her victim and stings it just below the head, temporarily paralysing its front legs. As the cockroach struggles to move, her second strike is made easier.
Snaking her stinger into the cockroach’s brain, the wasp essentially conducts brain surgery; using sensors on the tip of her stinger, she feels her way into specific regions, and deposits her venom exactly where it needs to be. This inactivates certain neurons in the roach’s brain, muting the natural fear that should arise when one has been taken captive by a mind-controlling wasp.
After delivering her venom, the wasp removes her stinger and simply walks away. When the first paralysing sting wears off, the cockroach is completely free to run and escape – but it doesn’t.
Carl Zimmer wrote in an article for National Geographic:
“The wasp returns – sometimes as long as half an hour later – and bites off one of the roach’s antenna. She slurps some roach juice from the wound, like a kid drinking a milkshake through a straw. Then she bites down on the antenna stump and guides the roach to her burrow, leading it as if it were a dog on a leash. The roach goes without a fight. The wasp leads the roach into the burrow and then lays an egg, shaped like a grain of rice, on its underside. Then she leaves the burrow, sealing it up to leave the roach in darkness.”
Over the course of the next week, the egg hatches and the larva uses the zombified roach as its first meal. Remember, the cockroach is still alive and healthy while this occurs – it has simply lost all free will and continues to stand in its captor’s burrow while a larva feeds on its insides.
The cockroach eventually dies, leaving behind an empty shell – a husk that serves as a perfect little home for the larva to develop eyes and legs and wings. About a month after the roach was sealed in the burrow, an adult jewel wasp bursts out of the cockroach’s corpse, ready to begin the zombifying process again. If only the poor cockroaches had an Ellen Ripley among them, because it seems Earth has its own kind of aliens.
For more detail, watch Carl Zimmer explain in his own words:
Feel like reading more about this evil alien insect? Check out The Daily Grail’s article here
