Date of Award

Summer 8-2010

Degree Type

Masters Thesis

Degree Name

Master of Science (MS)


Biological Sciences

Committee Chair

Jacob Schaefer

Committee Chair Department

Biological Sciences

Committee Member 2

Jennifer Regan

Committee Member 2 Department

Biological Sciences

Committee Member 3

Brian Kreiser

Committee Member 3 Department

Biological Sciences


The aim of the study was to characterize the reproductive behaviors of male and female blackspotted topminnows in the Pascagoula Drainage. I focused on phenotypic traits, size and number of dorsolateral spots, in males that possibly could cue a female to choose one male more frequently than other males present in the spawning group. With the use microsatellite markers, I was able to determine parentage in trial where a single female was allowed to choose among phenotypically different males. I found that in all trials one male mated with the female(s) present. I also found that in all cases the dominant male exhibited the secondary characteristic of large body size and, in most cases, a high number of dorsolateral spots compared to the other males. In the breeding tank, the dominant male did not defend a particular spawning territory but mated freely among the available spawning substrates. Concluding a nonrandom mating pattern was observed when females were presented with several males. These results suggest that females have a preference for large males with high number of dorsolateral spots, and males that possess secondary sex characteristics of large and higher frequency of dorsolateral spots mate more frequently than males that do not.