Identifying the Sexual Differences in the Neuromuscular Circuitry of Courtship Behavior in Cowbirds

Jakub working at a microscope

Students

2019
College

Faculty

Professor of Biology & Co-Director, Biological Basis of Behavior Program
College

Project Summary

This summer, I worked in the lab of Dr. Marc F. Schmidt in the Department of Biology, studying the sexual differences in the neuromuscular circuitry of courtship behavior in the brown-headed cowbird.

Currently in the songbird field, male zebra finches are used as the model organism for studying the neural circuitry of the song system, i.e., how song is learned and how it changes in response to feedback. However, the Schmidt Lab is laying the foundation for the study of the song system in females, who are proposed as the drivers of song change in males. In addition to focusing on females, a different, more suitable model organism is being used: the brown-headed cowbird.

One reason for the selection of the brown-headed cowbird as a model organism is the prominent courtship posture displayed by females when presented with a favorable song. When in this posture, called Copulation Solicitation Display (CSD), the female appears to be squatting with her chest near the ground and her tail in the air.

Marking the beginning of a new approach to studying the song system, much work is required to understand the basic anatomy of the cowbird during CSD before advanced experiments are performed. The goal of my project, as mentioned above, is to uncover the sexual differences in the neuromuscular circuitry of courtship behavior in the brown-headed cowbird. Throughout the school year, in order to understand gross anatomy, I first used anatomical atlases to study avian anatomy, focusing on the muscular system, and perform dissections.

With this knowledge, I was ready to record muscular activity using electromyography (EMG). During Spring Break, I was graciously sent by Dr. Schmidt to Salt Lake City, Utah to study EMG with Dr. Goller at the University of Utah.

During the summer, I spent the majority of my time constructing EMG electrodes, learning the basics of signal processing theory in order to obtain high-quality signal, and preparing methods for data analysis using MATLAB. Additionally, I learned how to design components for 3D printing. Near the end of the summer once all of this preparatory work was completed, I began preliminary neural- and muscular- recordings. 

Overall, it was very exciting to learn such a breadth of material, especially anatomy given my interest in medicine, and set up EMG, a tool which will be used by others in the lab in their studies of the song system. When learning about EMG from Dr. Goller, I experienced first-hand the power of collaboration in research. Additionally, the quantitative nature of this project will continue to allow me to refine my analytical skills. Thanks to my experience this summer, I now have a foundation for my independent research for my major.