by Blake Newton, UK Extension Entomologist
Every week, usually on Friday afternoon at 3pm, our department hosts a seminar. Last week, on Dec 4, Andy Boring was our speaker. Andy is a graduate student in Dr. Sharkey's laboratory. This was his exit seminar, and it was fascinating!
As a PhD student, Andy studied parasitic wasps in the scientific family Braconidae. Parasitic wasps are a little different than the wasps that most of us know. Parasitic wasps do not sting people. Instead, they sting other insects (& sometimes other arthropods, like spiders). When they do so, they place an egg, or multiple eggs, inside the host-insect's body. The eggs hatch and the larvae feed on the host, eventually killing it (yes, Alien from the movies WAS reportedly based on parasitic wasps!). This is common in the insect world: there are thousands of species of parasitic wasps, and each lays its eggs in a different type of insect.
A portion of Andy's PhD research focused on the ovipositors of parasitic wasps. Ovipositors are egg-laying devices found on the abdomens of many female insects. In parasitic wasps, the ovipositors are often long and thin--prefect for stinging small hosts. For many years, the mechanism of wasp oviposition was poorly understood. Andy's research was so interesting because he spent many hours dissecting these tiny stingers (they are thinner than needles!) and examining all of the internal structures. As it turns out, the ovipositors that Andy studied were made of three primary longitudinal sections. In other words, an ovipositor is actually three long, flexible segments that fit closely together to form a tube (imagine reassembling a banana from an empty peel!). Also located inside the tube is a series of small one-way valves that help to move the egg down--but not up--the ovipositor. And, when many parasitic wasps sting a host, they also inject venom and other fluids. Because of this, many ovipositors possess anatomical structures that facilitate the delivery of these fluids.
During his time here, Andy studied a bunch of other cool stuff about wasps as well. In particular, he discovered and named several different wasp species. This is actually quite common: Dr. Sharkey's students frequently discover and name new species of wasps. If you a interested in becoming a scientist, and if you want the thrill of discovering new species, entomology is the place to be. New insect species are being discovered ALL THE TIME. Hey Andy: if you see this post, can you write a follow-up post showing the total number of species that you named? UPDATE (12/10/09): Andy wrote a comment below about the insects that he named. Be sure to read it!
To learn more about wasp research in the Sharkey lab, visit the UK Hymenoptera Institute website. And you can learn more about our (free!) weekly seminar series here.