A tiny parasitic wasp injects a virus into ladybugs that turns them into zombie bodyguards for its young, a new study says.
The discovery of Dinocampus coccinellae's secret biological weapon, and its bizarre effect on the spotted lady beetle Coleomegilla maculata, reveals a devious new "mind control" strategy used by parasites. (Read "Mindsuckers" in National Geographic magazine.)
The newly described D. coccinellae paralysis virus (DcPV for short) marks the first known virus or other microorganism "involved in a behavioral manipulation that benefits another species," said study co-author Nolwenn Dheilly, a biologist at Stony Brook University in New York.
After being injected into the ladybug along with the wasp's egg, the virus replicates inside the growing wasp grub, which feeds on the insect's fluids.
Then, when the grub is ready to emerge and pupate, the virus infects the ladybug, causing paralysis.
Although the study team was able to detect the virus only in the ladybug's brain, "we believe it is able to infect the whole nervous system," said Dheilly, whose research appears February 11 in the journal Proceedings of the Royal Society B.
Once immobilized, the ladybug stands guard over the silk cocoon its former unwelcome guest has spun beneath it.
Since ladybugs are predators and contain toxic fluids, they make decent bodyguards, but the DcP virus may actually enhance their deterrent effect by making them twitch. (Related: "Pictures: Wasps Turn Ladybugs Into Flailing 'Zombies.'")
Dheilly thinks the virus is responsible for this twitching behavior, even if the link...