What's It Like to Be Parasitized?

Jan 7, 2015

What's it like to be parasitized?

Say you're a caterpillar or an aphid and a wasp comes along and lays her eggs inside you. Her eggs will hatch and then her offspring will eat their way out. You, the host,  are no more. Zero. Zip. Zilch.

If you visit the Bohart Museum of Entomology open house on Sunday, Jan. 11 on the University of California, Davis, campus, you'll learn all about parasitoids.

The fun, educational and family-friendly event is themed, "Parasitoid Palooza!" Free and open to the public, it takes place from 1 to 4 p.m. in Room 1124 of the Academic Surge Building on Crocker Lane,

"Most everyone knows that mantids eat other insects or that ladybird beetles (lady bugs) consume lots of aphids, but there is another way insects eat other insects," commented Tabatha Yang, education and outreach coordinator.

"An insect parasitoid is a species whose immatures live off of one insect host, usually eating it from the inside out," she said. "It is part of their life cycle and the host dies. This sounds like a weird way to make a living, but there are more species of parasitoids than there are insects with any other single kind of life history. The movie Alien with Sigourney Weaver co-opts this phenomenon, but in reality there are no parasitoids on humans or other vertebrates."

The Bohart open house will spotlight this unusual life cycle.  Wasps, flies and beetles are parasitoids to many different insect groups.

Senior museum scientist and collections manager Steve Heydon, is a world authority on Pteromalids, or jewel wasps, a group of tiny parasitoids, and will be on hand to talk about them.

Another group of parasitoids highlighted will be the Strepsiptera, or Twisted-Wing Parasites, an order of insects that the late UC Davis entomologist Richard M. Bohart (1913-2007) researched for his doctorate, which he obtained in 1938.  The museum not only carries his name, but there's an entire family of Strepsiptera, the Bohartillidae, named in honor of him.

Live parasitoids from the lab of Michael Parrella, professor and chair of the UC Davis Department of Entomolology and Nematology will be showcased. They include Encarsa, Eretmocerus, Diglyphus and Aphidius.

"Parasitoid Palooza" promises to be a fun and wacky celebration of the diversity of life, Yang said. A family-friendly craft activity with balloons inside of balloons (representing parasitoids) is planned.

Before you go, be sure to check out Wired.Com's piece on a wasp from the genus Glyptapantele laying eggs in a caterpillar. Tachinid flies also provide biological control services, laying their eggs in a number of insects, including  beetles, moths, sawflies, earwigs and grasshoppers.

Along with parasitoids, visitors will see some  "teddy bear" bees or male Valley carpenter bees, to be shown by native pollinator specialist Robbin Thorp, emeritus professor of entomology at UC Davis.   Allan Jones of Davis, a noted insect photographer, delivered some to Thorp's office in the Harry H. Laidlaw Jr. Honey Bee Research Facility last week. Their origin? A friend's felled apple tree in Davis. The tree had rotted and male and female Valley carpenter bees were wintering inside.

The Bohart Museum, directed by Lynn Kimsey, professor of entomology at UC Davis, houses a global collection of nearly eight million specimens. It is also the home of the seventh largest insect collection in North America, and the California Insect Survey, a storehouse of the insect biodiversity.

Special attractions include a “live” petting zoo, featuring Madagascar hissing cockroaches, walking sticks and tarantulas. Visitors are invited to hold the insects and photograph them. The museum's gift shop, open year around, includes T-shirts, sweatshirts, books, jewelry, posters, insect-collecting equipment and insect-themed candy.

The Bohart Museum's regular hours are from 9 a.m. to noon and 1 to 5 p.m. Mondays through Thursdays. The museum is closed to the public on Fridays and on major holidays. Admission is free. Open houses, focusing on specific themes, are held on weekends throughout the academic year. 

The remaining schedule of open houses:

  • Sunday, Feb. 8: “Biodiversity Museum Day,” noon to 4 p.m.
  • Saturday, March 14: “Pollination Nation,” 1 to 4 p.m.
  • Saturday, April 18: UC Davis Picnic Day, 10 a.m. to 3 p.m.
  • Sunday, May 17: “Name That Bug! How About Bob?” 1 to 4 p.m.
  • Saturday, July 18: “Moth Night,” 8 to 11 p.m.

More information is available by contacting Tabatha Yang, education and public outreach coordinator at tabyang@ucdavis.edu or (530) 752-0493.