Date Thesis Awarded


Access Type

Honors Thesis -- Open Access

Degree Name

Bachelors of Science (BS)




Eric Hilton

Committee Members

Dan Cristol

S. Laurie Sanderson

M. Lee Alexander


Cichlids are well-known for their capacity to exploit trophic niches in their environments through rapid speciation and morphological diversification; the best-documented case of such diversification in cichlids occurred in the African Rift Valley. With numerous species established in Florida, the purpose of this study was to explore how members of the family Cichlidae have managed to invade so successfully by focusing on morphological differences between native and non-native (Floridian) populations of three cichlid species: Pelmatolapia mariae, Mayaheros urophthalmus, and Parachromis managuensis. Using both linear measurements and 2D landmark geometric morphometry, I found that all three species have diverged in multiple characteristics. Additionally, P. mariae and P. managuensis have developed morphology beyond the range exhibited by endemic populations. The findings reported herein demonstrate that rapid morphological change has taken place among introduced populations of three cichlid species. The results suggest the observed morphological change may be the result of natural selection; however, further work is needed to test this hypothesis. Nevertheless, this study suggests that the conditions exist to promote rapid morphological evolution in introduced populations of cichlids in Florida.

Creative Commons License

Creative Commons Attribution-Noncommercial-No Derivative Works 4.0 License
This work is licensed under a Creative Commons Attribution-Noncommercial-No Derivative Works 4.0 License.

Available for download on Sunday, May 14, 2023

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