DISSERTATION RESEARCH: Covariation of opsin proteins and coloration in a Caribbean goby species complex

Louisiana State University, Baton Rouge LA

Investigators

Abstract

A grant has been awarded to Dr. Michael Hellberg and Mr. Michael Taylor at Louisiana State University to study whether the brilliant colors displayed by coral reef fishes are important for mate attraction and species recognition. Color perception by most vertebrate animals is conferred by proteins in the eyes called opsins. Color sensitivity of opsins can be altered by genetic changes to the genes coding for the proteins. The surrounding environment also affects color perception. The ecologically important cleaner gobies (genus Elacatinus) are brightly colored fishes that remove parasites from other fishes. Thus, coloration in cleaner gobies may be important both for mate recognition and for recognition by fishes that need cleaning. The investigators will determine whether changes in opsin proteins correspond with coloration changes of the cleaner gobies by comparing DNA sequences of opsin genes from two differently colored populations of a single species, and between two species with different colors. Additionally, the investigators will use an underwater spectroradiometer to quantify the color reflectivity of the corals occupied by these gobies to determine whether gobies choose coral colors that maximize the apparent intensity of their color display to other fishes. Coral reefs contain some of the greatest biodiversity on earth, and gobies are the largest family of marine fishes. This study will provide insight into the processes that lead to such diversity. Coloration differences between similar gobies can allow them to occupy different niches while advertising their cleaning services. An enhanced ability to distinguish potential mates by coloration could help to reduce genetic exchange between differently colored populations, leading to the formation of new species. Together, these concepts could provide clues about how environment and color vision interact to help generate the biodiversity observed on coral reefs.