From brain-munching fly larvae to snail-controlling parasitic worms, nature is full of fascinating examples of real-life zombification. Wasps are particularly good at using host species to do their bidding and Reclinervellus nielseni is no exception.
New research details the life cycle of this parasitoid wasp and its mind-controlling ability to "persuade" an orb spider to construct a special web for its larva. When the new home is complete and the host spider’s usefulness ends, the larva kills it and sucks out its insides. Aren’t wasps the best?
So here’s what we know. The host spider, Cyclosa argenteoalba, has at least two webs in its spinning repertoire: a classic orb design used for catching prey and a simpler "resting" web that it whips up just before moulting (spiders periodically shed their exoskeletons as they develop).
Spiders are vulnerable during moulting (like Iron Man without his suit), so the "resting" web is not designed to capture prey, but rather the opposite. Fibrous thread decorations make the web stand out so that swooping birds and other animals don’t crash into it. Cyclosa argenteoalba even uses fancy ultraviolet light-reflecting silk (like the spider version of aircraft warning lights) that make its web stand out. The only problem for the spider is that a cosy, well-protected web is rather appealing to wasp larva looking for a safe place to transition into the pupal phase.
Enter the wasp mamma. She attacks the spider and deposits an egg onto its abdomen. The larva quickly takes on the role of enslaver (they grow up so fast, don’t they?), using what the researchers suspect is a chemical process to convince the arachnid to build it a super-strong web similar to the resting variety described above.
Here's the spider in action ...
Researchers tested the breaking forces of the silk used to construct the larva lair and found it to be at least 2.7 times stronger than an ordinary web – it seems parasitic wasps make their spider hosts work hard.
Although the exact mechanisms of the zombification remain a mystery for now, lead author of the research, Keizo Takasuka, believes that it is somehow connected to a hormone that the spider naturally releases just before molting. It’s this hormone that motivates the spider to construct a resting web.
So look out, spiders. The zombie apocalypse is here.