A Geometric Morphometric Analysis of Tail Morphology in the Colombia Spotted Frog, Rana lutieventris

Abstract

Phenotypic plasticity is the result of environmental factors interacting with genes to influence the phenotype of individuals. Developing amphibian larvae may be influenced by the presence of tadpole predators. Rana lutieventris tadpoles were reared in the presence of a predator, presence of an injured conspecific, presence of both a mashed conspecific and predator, and a control of no predator or conspecific for a period of six weeks. Photographs were taken weekly to monitor tail growth. The photographs were digitized and the data was analyzed using geometric morphometries. Geometric morphometric software pooled the data, eliminated differences in size, position, and orientation to analyze the shape differences between the tadpoles in these four treatments. The data was statistically analyzed using multivariate analysis of covariance (MANCOVA). All three experimental treatments were found to cause enlarged tails, showing that R. lutieventris has the ability to respond to chemical cues and exhibit phenotypic plasticity.