However, the ladybug does not die, but is partially paralyzed and se keeps sitting on the parasite while serving as a protective shield “bodyguard”. Researchers believe that the wasp’s venom causes the ladybug to fidget and contract, thus scaring away predators.Biology Letters. In experiments in the laboratory, Jacques Brodeur, Maure Fanny and their colleagues at the University of Montreal in Canada showed that the cocoon cared for by a live ladybug were significantly less prey to natural enemies than those found alone or covered by dead ladybugs.
Of the ladybugs that become bodyguards for the wasps, the researchers found thatabout 25% recovered from the ordeal. However, turning the ladybug into a protective cocoon comes at a high cost to the parasitic wasp, according to the researchers. They observed that the longer they keep ladybugs alive, the waspsbecome less fertile as adults, and they lay fewer eggs. The explanation is that the parasite needs to support the ladybug and also needs to develop the eggs, two competing demands that depend on the same resources.
