comment in Nature
Nature 457, 361 (22 January 2009) | doi:10.1038/457361a; Published online 21 January 2009
Entomology: Hammers of the wasps
Biol. J. Linn. Soc. 96, 82–102 (2009)
A number of parasitic wasp species have independently evolved echolocation techniques to find host insects deep within trees.
Several species of parasitic wasp attack beetle larvae living inside wood, leading researchers to wonder how they find their prey. To this end, Nina Laurenne at the Museum of Natural History in Helsinki and her colleagues have surveyed the hammer-shaped antennal tips that these species whack against the trees. This hammering allows the wasps to locate the regions where they are wont to find their prey.
A phylogenetic analysis conducted by the researchers suggests that these hammers are not a one-off innovation and have appeared and disappeared during the course of evolution, seemingly in response to the needs of wasp species moving into this niche.
Origonal Paper
http://www3.interscience.wiley.com/jour ... 1&SRETRY=0
Hammering homoplasy: multiple gains and losses of vibrational sounding in cryptine wasps (Insecta: Hymenoptera: Ichneumonidae)
NINA LAURENNE, NIKOS KARATOLOS and DONALD L. J. QUICKE
ABSTRACT
Many hosts of parasitic wasps are, when attacked, either at an immobile stage, living in a concealed environment, or both, thus making their detection especially difficult. Cryptine ichneumonid wasps often parasitize beetle or moth larvae, prepupae or even pupae in tunnels in wood, and many others attack cocooned hosts in various states of concealment. The structure of the antennal tips shows a range of adaptations at least the most extreme of which appear to be involved in locating deeply concealed hosts through vibrational sounding (= echolocation through solid media). We show that, within the Cryptinae, the tips of the antenna are modified into a hammer-like structure that is suitable for knocking a substrate; this form of echo-location is typical to the tribe Cryptini, although it is also found in a few phygadeuontines and in the hemigastrine genus Echthrus. Electron micrographs are presented to illustrate the different degrees of antennal modifications found in the subfamily. Comparative analysis using independent contrasts was then used to demonstrate a statistically significant association between degree of antennal hammer development and attacking, typically wood-boring, beetle hosts of the families Cerambycidae and Buprestidae.
Biological Journal of the Linnean Society, 2009, 96, 82–102.