USF St. Petersburg campus Honors Program Theses (Undergraduate)

First Advisor

Thesis Director: Alison Gainsbury, Ph.D.


University of South Florida St. Petersburg

Document Type


Date Available


Publication Date


Date Issued



The applications of Bergmann’s rule on nocturnal squamates has rarely been examined. Bergmann’s rule states that species increase in size with increasing latitude. The relationship between latitudinal gradients and body size may shed light on the mechanisms these geckos use to function under suboptimal temperatures. This study examined maximum body size in relationship to absolute latitude in 33 of the 132 Hemidactylus species. The objective of the study was to test the inverse of Bergmann’s rule, thus testing if lizard body sizes decrease towards higher latitudes. Data was collected from literature and the following two databases, Vertnet and The Reptile Database. I performed a regression analyses to determine whether there is an association between body size and latitudinal gradient. The results indicate no support for the relationship between maximum body size and latitude in the studied species. There was also a lack of support that sexual dimorphism has an effect on the association between maximum body size and latitude. These results support that the inverse of Bergmann’s rule does not apply to the studied Hemidactylus species, indicating these species do not require smaller body sizes to function under suboptimal temperatures.


A thesis submitted in partial fulfillment of the requirements of the University Honors Program University of South Florida St. Petersburg

Creative Commons License

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