Publication Date

Spring 2020

Advisor(s) - Committee Chair

Dr. Steve Huskey (Director), Dr. Jarrett Johnson, and Dr. Michael Smith

Degree Program

Department of Biology

Degree Type

Master of Science


Substrate-borne vibrations, or biotremors, are utilized by vertebrates found in unique environments because biotremors are an effective way to transmit signals through dense media. Previous studies have shown that veiled chameleons (Chamaeleo calyptratus) are able to produce biotremors via specialized neck muscles. I hypothesized that during courtship and/or breeding, the veiled chameleon, a tree-dwelling species, would communicate with biotremors through branches. Additionally, I hypothesized that female call characteristics would differ between reproductive condition (i.e., receptive and non-receptive), while male call characteristics would differ between behavioral contexts (i.e., territorial vs. courtship). Chameleons were paired (one male, one female) and placed on a wooden dowel to create an optimal setting for reproductive behavior, and the biotremors produced by each chameleon were recorded with accelerometers and characterized by the type of call (hoot or rumble), duration (s), and dominant frequency (Hz). Linear mixed-effect models and ANOVAs were used to analyze the effect that variables such as sex, receptivity of the female, snout-vent length (SVL), and behavioral context had on the biotremors being produced. Both receptivity of females and SVL had an effect on female hoot and rumble frequencies, while receptivity of females had an effect on the duration of female rumbles. Additionally, behavioral context affected male hoot frequency. These results reflect how females could be able to advertise receptivity utlilizing biotremors. While males could potentially communicate their presence to females or competing males within range.


Behavior and Ethology | Biology | Ecology and Evolutionary Biology | Other Life Sciences