Horrifying wasp brainwashes spiders into zombie babysitters

BY JAMES GORMAN

If spiders had nightmares, the larvae of ichneumonid wasps would have to star in them. The wasp lays an egg on the back of an orb weaver spider, where it grows fat and bossy, and occupies itself with turning the spider into a zombie. As Keizo Takasuka and his colleagues point out in The Journal of Experimental Biology, this is a classic case of “host manipulation.” Using more colorful language, he described the larva turning the spider into a “drugged navvy.”

The larva forces the spider to turn its efforts away from maintaining a sticky, spiral web to catch prey, and to devote itself to building a safe and sturdy web to serve as a home for the larva’s cocoon, in which it will transform itself into a wasp.

This process was well known, but Dr. Takasuka and Kaoru Maeto at Kobe University, working with other Japanese researchers, wanted to explore how the wasp overlords controlled their spiders.

Read the full story in the New York Times.

Photo via Tony Alter/Flickr (CC BY 2.0)