I realize that these types of biological oddities are not everyone’s cup of tea, but I can’t get over how fascinating some parasites/parasitoids can be! Especially the ones that interfere with a host’s nervous system. This recently-released research is brought to you by my alma mater, Rice University. I am slightly jealous that this was not the focus of my undergraduate research, but studying cannibalistic zooplankton was cool too! Back to wasps…
These iridescent, innocent-looking wasps are actually mind-manipulating machines. Crypt-keeper wasps lay their eggs in or near crypt gall wasps that are already happily incubating in a comfy tree crypt of their own. Somehow crypt-keeper wasps are able to manipulate gall wasps into burrowing out of the tree branch. However, there is a partial disconnect in information registering in the brains of gall wasps as they proceed to burrow tunnels that are not large enough for their entire bodies to fit through. Consequently, gall wasps get lodged in the tunnel. Once crypt-keeper wasps are fully matured, they eat their way through the soft body tissue of the gall wasps and to freedom. Crypt-keeper wasps are not well adapted to burrowing out of their wooden fortresses alone. In fact, the researchers stated that if they covered a gall wasp’s lodged head with an extra layer of bark, the crypt-keeper wasps were three times more likely to die because they could not burrow through the bark on their own. Rice University also put together a short video about the crypt-keeper/gall wasp dynamic!
If you want to continue on your adventure into zombie biology, better known as neuroparasitology, try checking out this video about the jewel wasp, or emerald cockroach wasp. The jewel wasp hunts solely on American cockroaches and gives the cockroaches a precise dose of venom straight to the brain that allows the wasp to lead the cockroach back to its burrow, where the wasp lays an egg on the cockroach. The jewel wasp then barricades the cockroach inside of the nest. About a month later, a new jewel wasp will emerge, having been sustained on the nutrients provided by the unwilling host.
I also found a great Nat Geo video on another type of wasp that uses caterpillars as their host. In my opinion, this was the trippiest of all three videos that I am presenting because not only do the larvae eat their way out of the caterpillar, but the caterpillar SURVIVES. Watch the video! We are not talking about just one larva either. A multitude of larvae come out of this caterpillar! The craziest part is that the caterpillar sticks around and helps them! The caterpillar will finish the protective silken blanket that covers the wasp larvae as they incubate. Moreover, the caterpillar then continues to protect the wasp larvae until it dies of starvation. WHAT?! Biology is best! If you had a rough day today, just be grateful that you are not an insect!