You may know of the number of parasitic wasp species that are able to dump their larvae on different insect species, which then take control of their brain while also eating them as they carry on in a zombie-like state until they eventually die. As if there weren’t enough of these parasitic wasps hanging around and messing up insect’s live already, another one has been discovered that is able to take over the brains of a certain species of social spider. What’s worse is that they always latch onto the adolescent spiders, ruining their lives before they’ve even started. Now that’s a raw deal.
A rather remarkable species of social spider, Anelosimus eximius, inhabits parts of Latin America. These guys aren’t just a little social, though. They live in colonies made up of thousands of these spiders. These spiders live near the forest floor in basket-shaped webs that can be up to 25 feet wide. These webs are attached to the vegetation near the forest floor, and this is where colony of spider work cooperatively to protect their eggs and raise their spiderlings. The entire colony also works together to attain larger prey such as grasshoppers when they happen to accidentally blunder into the silk lines that stick out all over their webs and fall in. This species is a pretty amazing example of social spiders.
Unfortunately, they have one major predator out there that is targeting their young adolescents and turning them into zombie hermits. Philippe Fernandez-Fournier, a doctoral student at Simon Fraser University in British Columbia, discovered this species of wasp that has never been named or described in any scientific literature discovered these parasitic wasps while he was in Latin America studying the spiders just mentioned. He was amazed and horrified at the way these parasitic wasps are able to bend these spiders to their will.
The wasp basically camps outside one of the spiders’ webs waiting for one of the younger spiders to stray from the safety of the colony. Fernandez-Fournier suggests that they may prefer the adolescent spiders because they have softer shells and are “less feisty,” making them easier to abduct and control. While scientists still aren’t sure exactly how the wasp larvae actually ends up on the spider, they do know that once there, they start feeding on the abdomen. The larvae is able to begin controlling the spider’s brain as it grows, and force it to leave the safety of the colony to live more like a hermit, alone and at the complete mercy of the wasp larvae. The young spider then weaves silk cocoon around itself to seal it off from the outside world. The larvae then eats the rest of the spider and builds its own cocoon inside of the convenient silk ball it is already inside, and pupates into an adult wasp.
What other parasitic wasps or insects do you know of? Which sounds the worst?