No Nose, No Mouth, No Problem: the Silkmoth Story
Hi all! I’m Jess. I’m a senior neuroscience major from Westminster College in Salt Lake City, UT. It’s a small, private liberal arts school you’ve probably never heard of, but I promise you it’s the best small, private liberal arts school you’ve probably never heard of (with an awesome neuroscience program). Prior to my academic endeavors, I was a U.S. Ski Team member and competed in the sport of slopestyle, which involves a variety of jumps, spins, and grabs through the terrain park.
Training at Keystone Mountain, CO in December 2015
After four seasons on the ski team, I retired to pursue my degree. I still ski in my free time, but have also picked up a variety of hobbies including, climbing, mountain biking, and canyoneering. So far, the mountain biking in the Ann Arbor area has been amazing, and I look forward to exploring more!
This summer I will be working on Bombyx mori, or the domestic silkworm moth. In addition to producing valuable silk, this species has been well studied due to its interesting mating behavior. As shown below, silkworm moths go through multiple stages of development. Most of their life is spent in a larval stage eating mulberry leaves. Once they are large enough, they spin a silk cocoon around themselves and develop into a moth.
Silkworm moths only live to 5-10 days after emerging from their cocoon because they are incapable of eating or drinking. Their singular goal during this time is to find a mate as quickly as possible and reproduce. Observations from the early 1900s reported that female moths were unable to attract males if they were covered by a glass cup. This suggested that the females were emitting some sort of chemical to attract the males, but how could the male silkmoths sense it without a nose?
It turns out that silkmoths males have extremely sensitive antenna that are capable of detecting pheromones, or chemical substances that cause a change in behavior. Further, female silkmoths release a pheromone called bombykol that attracts males up to 10 kilometers away. Crazy. This discovery initiated a field of research investigating the molecular and neural mechanisms responsible for mating behavior in silkmoths.
Adult male silkmoth with pronounced antennas
This is an accessible insect that has a tractable behavior, so you may ask yourself, “How has Backyard Brains never studied this!?” Well, we have. While significant progress was made in the summer of 2015, the project was never completed. This summer, I will be revamping this project with the goal of producing a lab for the classroom. I will be changing the behavioral task, adding some different stimulants, and investing local field potentials in higher order brain structures in addition to electroantennogram recordings.
I am currently in the midst of ordering materials. The moths are going to take a bit of time to get here and hatch, so in that time I will be trying out my new methods on cockroaches and seeing if they will work. Wish me luck!