Big fleas have little fleas,
Upon their backs to bite ‘em,
And little fleas have lesser fleas,
and so, ad infinitum.
So goes the nursery rhyme. Lady Beetles are not without their own set of parasites. One parasitic wasp Dinocampus coccinellae, develops inside the body of the Lady Beetle. When the wasp is fully grown, it makes a hole in the abdomen of the Lady Beetle, crawls outside and spins a cocoon between the legs of the lady beetle. Lady Beetles are fierce predators so other insects avoid them. Lady Beetles taste bad, so insectivorous birds avoid them The parasitic wasp paralyzes the Lady Beetle so that it “stands guard”, protecting the cocoon until the adult wasp emerges.
Many examples of parasitism in insects are lethal. The parasite kills the host insect. In this interaction, the Lady Beetle survives about 20 percent of the time. Eventually the paralysis will wear off and the adult Lady Beetle will live a normal Lady Beetle life feeding on aphids. For more information, see the full article in Biology Letters:
Fanny Maure, Jacques Brodeur, Nicolas Ponlet, Josée Doyon, Annabelle Firlej, Eric Elguero and Frédéric Thomas, “The cost of a bodyguard,” Biology Letters (2011)
doi: 10.1098/rsbl.2011.0415
Left: The larva breaking through the ladybird's abdomen.
Photo: Mathieu Bélanger Morin –CNRS/IRD
Right: Manipulated ladybird playing the role of bodyguard.
Photo: Pascal Goetgheluck
