Wasps doing brain surgery
Very interesting post about Ampulex compressa, a species of tropical African wasp. Like many other solitary wasps, A. compressa lays its eggs on another insect, which is then used as food by the wasp’s larvae. However, our wasp has picked Periplaneta americana, an African cockroach (not American, despite the misleading name), as the host for its eggs. The cockroach is much larger than the wasp, so the little wasp can’t just kill the roach and drag it back to the burrow. And here the story gets fascinating.
A. compressa has learned to perform brain surgery on P. americana. It immobilizes the cockroach with a venomous sting to the midsection, and then inserts its stinger directly into the cockroach’s brain. Sensors on its stinger allow it to reach precisely the right spot in the brain to deliver a mixture of dopamine and neurotoxins. Half an hour after being stung, the cockroach 1. loses its escape instinct; and 2. enters a state of hypokinesia (greatly lowered metabolism). The wasp then simply leads the “zombified” roach by its antennae back to the burrow. Inside the burrow, the wasp parks the lobotomized cockroach and lays an egg on its underside. Soon, a wasp larva hatches from the egg, enters the roach’s body, and eats the insides of the poor roach for 8 days. Because the cockroach’s metabolism has been lowered, it remains alive for 6-7 days of the feeding process. Thus, the mother’s sting provides the little larva with fresh meat. After 8 days, the larva makes a cocoon inside the roach’s corpse, completes its metamorphosis, and bursts out to mate and repeat the cycle.
Horror movie directors have much to learn from Mother Nature.
The PubMed abstract can be found here.