Faculty Sponsor
Michi Tobler
Final Abstract for URS Program
Cave-adapted organisms often exhibit pronounced morphological changes relative to their surface counterparts, a phenomenon known as troglomorphy. In Poecilia mexicana (Atlantic molly), these differences include variation in coloration between surface and cave populations. Troglobitic organisms also typically exhibit reduced metabolic rates, likely as an adaptation to environments with low primary productivity. This makes P. mexicana an ideal system for investigating the evolution of metabolic traits. In this study, we leveraged variation in coloration among cave-dwelling mollies to examine potential associations with resting metabolic rate (RMR). Coloration was quantified using PCR values, and individuals were categorized as “yellow” or “non-yellow.” We then compared RMR between groups while accounting for body mass. We found that yellow individuals were predominantly restricted to completely dark cave chambers. Contrary to expectations, yellow fish exhibited slightly higher RMR than non-yellow fish. Additionally, the relationship between coloration and metabolic rate was stronger in yellow individuals. These results suggest that yellow pigmentation is not associated with reduced metabolic rate in cave mollies. Instead, other traits or mechanisms are likely responsible for the lower metabolic rates observed in cave-adapted populations.
Presentation Type
Visual Presentation
Document Type
Article
Included in
Comparative and Evolutionary Physiology Commons, Evolution Commons, Population Biology Commons, Terrestrial and Aquatic Ecology Commons, Zoology Commons