Natural Resources, School of


First Advisor

Joseph Dauer

Date of this Version

Summer 8-1-2019

Document Type



Spier, S. (2019). Traffic Noise and Sexual Selection: Studies of Anthropogenic Impact on Bird Songs and Undergraduate Student Reasoning of Evolutionary Mechanisms. M.S. thesis, University of Nebraska-Lincoln.


A THESIS Presented to the Faculty of The Graduate College at the University of Nebraska In Partial Fulfillment of Requirements For the Degree of Master of Science, Major: Natural Resource Sciences, Under the Supervision of Professor Joseph Dauer. Lincoln, Nebraska: August, 2019

Copyright 2019 Sarah Spier


Humans have transformed much of the natural landscape and are continuing to do so at an accelerated rate, compromising natural areas that serve as important habitat for many species. Roads impact much of the environment as they fragment habitat and introduce traffic noise into the acoustic environment, deferentially affecting wildlife in roadside habitat. I explored how traffic noise affects the detection of birds based on whether their vocalizations were masked by traffic noise. Masked species detection was not affected by an increase in traffic noise amplitude, while there was a negative effect of traffic noise amplitude on unmasked species detection, an unexpected result. Conducting more experiments on individual species detection will help ecologists better understand the changes in behavior that influence detection. The effect of human activity on the environment should be better understood by more than just ecologists. Yet, people in the United States fall behind other developed countries in their understanding of many scientific processes, such as evolution. Improved evolutionary knowledge leads people to have a higher acceptance of evolution, and biology educators are responsible for improving evolution education to promote more acceptance. For example, biology students seem committed to survival-based reasoning of evolution, but there are other important evolutionary forces to consider, such as sexual selection. Multiple selection pressures can act on a species, including pressures that select for traits that are maladaptive for survival. Through interviews, we explored how selection for the same and different trait variants affected student reasoning of evolution. When asked to describe evolution in a scenario where selection favored the same variant of a trait, students relied on survival-based reasoning. When students were presented with a scenario where different selection pressures selected for different trait variants, most students described how sexual selection acted on the traits of the population and included reproductive potential as a component of fitness and inheritance in their descriptions of evolution. Teaching examples with scenarios where different selection pressures are selecting for different traits may improve student ability to reason about the role of sexual selection in evolution and the role of reproductive potential in fitness, improving overall understanding of evolution.

Advisor: Joseph T. Dauer