Taking Aim
The parasitic wasp Dinocampus coccinellae prepares to inject a spotted ladybug with a single egg in a file picture. The ladybug has been paralyzed by the wasp's venom.
In time the egg will hatch into a larva that will develop for a few days and then chew a small hole through the abdomen of the ladybug. The larva will then spin a cocoon between the legs of the ladybug, whose body will rest on top of the cocoon as the larva undergoes metamorphosis. (See insect-egg pictures.)
In a recent study in the journal Biology Letters, scientists note that sometimes the ladybugs survive the larva's emergence, and in those cases, the D. coccinellae larva then "brainwashes" the bug into defending the vulnerable cocoon from predators, said study co-author Jacques Brodeur, a biologist at the University of Montreal.
"The parasite is taking control of the behavior of its host—that's why we call it bodyguard manipulation," said Brodeur, who worked with Ph.D student Fanny Maure.
(See "'Zombie' Roaches Lose Free Will Due to Wasp Venom.")
—Christine Dell'Amore
Pictures: Wasps Turn Ladybugs Into Flailing "Zombies"
A parasitic wasp "brainwashes" ladybugs into hosting and then aggressively defending the wasp's developing larvae, a new study says.
