I did not know this. Being a giant relative to cockroaches, I’d only imagined mashing the whole animal into a pulpy mass between my molars, but apparently, with a lesser size difference, one can be a connoisseur of the flavors of different meats in the prey animal, and appreciate the subtleties of the meal. As the emerald jewel wasp does.
And so, in another attempt to win his students’ attention, the scientist set out to film an emerald jewel wasp larva as it feasted on the cockroach from within.
“That’s the way science often unfolds for me,” said Dr. Catania, the author of “Great Adaptations.” “I’m looking at something out of curiosity, or art.”
This is how he ended up capturing the larva’s taste for cockroach heart. But he made an unexpected discovery: After eating the heart of the cockroach, the wasp larva started gnawing at its quarry’s trachea, the insect equivalent of lungs. This caused air to leak out of the cockroach’s respiratory system and into its body cavity, air that the wasp larva then eagerly slurped up.
In other words, the emerald jewel wasp both eats the cockroach’s heart out and takes its breath away.
After performing the experiment two dozen times, Dr. Catania was able to show that not only do the air bubbles allow the larva to breathe while fully inside the cockroach’s body, but they also give the little hell-raiser a metabolic boost. Once the air bubbles appear, the larvae start to chew faster, which Dr. Catania documented this year in a study published in the journal Current Biology.
Now that’s an interesting twist. When you’re head first in the gooey, slimy, liquid interior of the victim you’re eating, respiration becomes a problem — so you suck air out of its respiratory system. Brilliant! I’ll remember that next time I dive into the body of an animal 50 times my size.
There’s a video if you’d like to see a living cockroach heart get eaten by a wasp. It’s cute and heartwarming.