The Crazy Relationship Between the Jewel Wasp, Zombie Cockroaches, and Karate Kicks
“Zombie cockroach” sound like something out of a horror movie. But they are not fiction at all. It’s all due to the emerald cockroach wasp, also known as the “jewel wasp.” The wasps have a bluish-green metallic body. Yet what makes them most interesting is that the female wasps have to lay their eggs in a living cockroach, which then serves as the food source for wasp larvae.
The biological challenge is that the American cockroach they need for this process is much larger than the wasp. In order to keep the roach from fighting back, the jewel wasp uses her stinger to inject 2 shots of venom. The venom turns the cockroach into a “zombie” that the wasp can then lead around safely and use to feed its young.
How Cockroaches Evade Attacks from Emerald Cockroach Wasps
But that is not the end of the story.
The emerald cockroach wasp uses its teeth to latch onto the cockroach and delivers its first sting into the thorax. This paralyzes the roach’s front legs for a short time, making it possible for the wasp to sting into the roach’s brain. This sting blocks any will and desire to escape, turning it into essentially a zombie.
The wasp leads the zombie roach to its burrow, lays 1 or 2 eggs on the roach’s body, and fills in the burrow to protect it from predators. The eggs take 3 to 4 days to hatch. After hatching, the larvae will spend the next week consuming the roach’s body – while it is alive – until the roach finally dies when they consume its internal organs. Throughout this period, the venom from the wasp keeps the roach from ever trying to escape.
That first sting is the most critical. Once the wasp is able to inject its venom, the rest of the roach’s life is over. So cockroaches have had to evolve a way to fight back against the wasp and prevent its sting, and here’s where it gets even more interesting:
Cockroaches can karate kick.
As the jewel wasp comes near, the roach will kick out with one of its back legs, similar to a karate kick, ideally hitting the wasp in the head. Since the wasp’s sting has to be precise to get into the ganglia regions, the karate kick pushes it away and prevents that first sting from hitting the critical spot. That also gives the cockroach time to run away to safety.
If a karate kick is not possible, roaches have other strategies they can use, including:
- Biting the wasp first.
- Standing on legs on only one side to get the thorax away from the wasp.
- Rotating rapidly to dislodge the wasp.
- Using the spines on their legs to remove the wasp and stinger.
- Running away to escape a sting.
Since jewel wasps are traditionally only found in Asia, Africa, South America, and the Pacific Islands, you probably will not catch cockroaches in NYC displaying any martial arts moves. Instead, get a close up look at how roaches fight off jewel wasps in this video from National Geographic.
And if you are dealing with an infestation at your home, apartment, condo, or co-op in NYC, call 24 Hour Pest Control. You may not be struggling with zombie roaches or fighting roaches, but they can still be extremely hard to get rid of without professional tools and treatments.