Although behaviors can be flexible, behavioral tendencies (e.g., the reactivity of individuals) may be heritable, and it is possible that behavioral tendencies evolve via natural selection. For example, in high-risk environments, individuals that exhibit greater vigilance and/or reactivity may be better at avoiding predators and thus have a fitness advantage over less vigilant individuals. In low-risk environments, vigilance/reactivity may be a disadvantage for fitness if it results in fewer opportunities to feed. Marine fishes often behave differently among populations experiencing differences in risk, but it is not clear whether such differences in behavior are innate or learned. I tested whether black surfperch (Embiotoca jacksoni) from high- and low-risk populations exhibited differences in reactivity. In field surveys, surfperch in high-risk locations had larger Flight Initiation Distances than surfperch in relatively low-risk locations. In a test of whether these behavioral differences are inherited, I collected pregnant fish from a high-risk population (Santa Catalina Island) and a low-risk population (Palos Verdes). In this “common garden” experiment, I compared the behaviors of lab-born offspring. Fish from the high-risk population exhibited greater reactivity, had higher swimming velocities, and spent less time sheltering than fish from the low-risk population. Though the overall differences persisted, in repeated trials over time I found that these populations become increasingly similar when reared in a common lab environment. These results suggest that innate behavioral differences may evolve in response to spatial differences in predation risk. However, a degree of behavioral plasticity is maintained, and even though individuals may differ with respect to their overall behavioral tendencies, behaviors can be adjusted in response to current environmental conditions.
|Advisor:||Johnson, Darren W.|
|Commitee:||Steele, Mark A., Lowe, Christopher G.|
|School:||California State University, Long Beach|
|School Location:||United States -- California|
|Source:||MAI 81/2(E), Masters Abstracts International|
|Subjects:||Biology, Biological oceanography|
|Keywords:||Antipredator behavior, Behavioral tendency, Black surfperch, Local adaptation, Reactivity, Temperament|
Copyright in each Dissertation and Thesis is retained by the author. All Rights Reserved
The supplemental file or files you are about to download were provided to ProQuest by the author as part of a
dissertation or thesis. The supplemental files are provided "AS IS" without warranty. ProQuest is not responsible for the
content, format or impact on the supplemental file(s) on our system. in some cases, the file type may be unknown or
may be a .exe file. We recommend caution as you open such files.
Copyright of the original materials contained in the supplemental file is retained by the author and your access to the
supplemental files is subject to the ProQuest Terms and Conditions of use.
Depending on the size of the file(s) you are downloading, the system may take some time to download them. Please be